Merge remote-tracking branch 'hathach/master' into cdc_without_dtr

34 files changed, 2320 insertions, 208 deletions

diff --git a/examples/device/audio_test/.skip.MCU_SAMD11 b/examples/device/audio_test/.skip.MCU_SAMD11
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/examples/device/audio_test/.skip.MCU_SAMD11
diff --git a/examples/device/audio_test/.skip.MCU_SAME5X b/examples/device/audio_test/.skip.MCU_SAME5X
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/examples/device/audio_test/.skip.MCU_SAME5X
diff --git a/examples/device/audio_test/.skip.MCU_SAMG b/examples/device/audio_test/.skip.MCU_SAMG
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/examples/device/audio_test/.skip.MCU_SAMG
diff --git a/examples/device/audio_test/Makefile b/examples/device/audio_test/Makefile
new file mode 100644
index 000000000..5a455078e
--- /dev/null
+++ b/examples/device/audio_test/Makefile
@@ -0,0 +1,12 @@
+include ../../../tools/top.mk
+include ../../make.mk
+
+INC += \
+  src \
+  $(TOP)/hw \
+
+# Example source
+EXAMPLE_SOURCE += $(wildcard src/*.c)
+SRC_C += $(addprefix $(CURRENT_PATH)/, $(EXAMPLE_SOURCE))
+
+include ../../rules.mk
diff --git a/examples/device/audio_test/src/main.c b/examples/device/audio_test/src/main.c
new file mode 100644
index 000000000..7f0ce3652
--- /dev/null
+++ b/examples/device/audio_test/src/main.c
@@ -0,0 +1,422 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Reinhard Panhuber
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "bsp/board.h"
+#include "tusb.h"
+
+//--------------------------------------------------------------------+
+// MACRO CONSTANT TYPEDEF PROTYPES
+//--------------------------------------------------------------------+
+
+/* Blink pattern
+ * - 250 ms  : device not mounted
+ * - 1000 ms : device mounted
+ * - 2500 ms : device is suspended
+ */
+enum  {
+  BLINK_NOT_MOUNTED = 250,
+  BLINK_MOUNTED = 1000,
+  BLINK_SUSPENDED = 2500,
+};
+
+static uint32_t blink_interval_ms = BLINK_NOT_MOUNTED;
+
+// Audio controls
+// Current states
+bool mute[CFG_TUD_AUDIO_N_CHANNELS_TX + 1]; 						// +1 for master channel 0
+uint16_t volume[CFG_TUD_AUDIO_N_CHANNELS_TX + 1]; 					// +1 for master channel 0
+uint32_t sampFreq;
+uint8_t clkValid;
+
+// Range states
+audio_control_range_2_n_t(1) volumeRng[CFG_TUD_AUDIO_N_CHANNELS_TX+1]; 			// Volume range state
+audio_control_range_4_n_t(1) sampleFreqRng; 						// Sample frequency range state
+
+// Audio test data
+uint16_t test_buffer_audio[CFG_TUD_AUDIO_TX_FIFO_SIZE/2];
+uint16_t startVal = 0;
+
+void led_blinking_task(void);
+void audio_task(void);
+
+/*------------- MAIN -------------*/
+int main(void)
+{
+  board_init();
+
+  tusb_init();
+
+  // Init values
+  sampFreq = 44100;
+  clkValid = 1;
+
+  sampleFreqRng.wNumSubRanges = 1;
+  sampleFreqRng.subrange[0].bMin = 44100;
+  sampleFreqRng.subrange[0].bMax = 44100;
+  sampleFreqRng.subrange[0].bRes = 0;
+
+  while (1)
+  {
+    tud_task(); // tinyusb device task
+    led_blinking_task();
+    audio_task();
+  }
+
+
+  return 0;
+}
+
+//--------------------------------------------------------------------+
+// Device callbacks
+//--------------------------------------------------------------------+
+
+// Invoked when device is mounted
+void tud_mount_cb(void)
+{
+  blink_interval_ms = BLINK_MOUNTED;
+}
+
+// Invoked when device is unmounted
+void tud_umount_cb(void)
+{
+  blink_interval_ms = BLINK_NOT_MOUNTED;
+}
+
+// Invoked when usb bus is suspended
+// remote_wakeup_en : if host allow us  to perform remote wakeup
+// Within 7ms, device must draw an average of current less than 2.5 mA from bus
+void tud_suspend_cb(bool remote_wakeup_en)
+{
+  (void) remote_wakeup_en;
+  blink_interval_ms = BLINK_SUSPENDED;
+}
+
+// Invoked when usb bus is resumed
+void tud_resume_cb(void)
+{
+  blink_interval_ms = BLINK_MOUNTED;
+}
+
+//--------------------------------------------------------------------+
+// AUDIO Task
+//--------------------------------------------------------------------+
+
+void audio_task(void)
+{
+  // Yet to be filled - e.g. put meas data into TX FIFOs etc.
+  asm("nop");
+}
+
+//--------------------------------------------------------------------+
+// Application Callback API Implementations
+//--------------------------------------------------------------------+
+
+// Invoked when audio class specific set request received for an EP
+bool tud_audio_set_req_ep_cb(uint8_t rhport, tusb_control_request_t const * p_request, uint8_t *pBuff)
+{
+  (void) rhport;
+  (void) pBuff;
+
+  // We do not support any set range requests here, only current value requests
+  TU_VERIFY(p_request->bRequest == AUDIO_CS_REQ_CUR);
+
+  // Page 91 in UAC2 specification
+  uint8_t channelNum = TU_U16_LOW(p_request->wValue);
+  uint8_t ctrlSel = TU_U16_HIGH(p_request->wValue);
+  uint8_t ep = TU_U16_LOW(p_request->wIndex);
+
+  (void) channelNum; (void) ctrlSel; (void) ep;
+
+  return false; 	// Yet not implemented
+}
+
+// Invoked when audio class specific set request received for an interface
+bool tud_audio_set_req_itf_cb(uint8_t rhport, tusb_control_request_t const * p_request, uint8_t *pBuff)
+{
+  (void) rhport;
+  (void) pBuff;
+
+  // We do not support any set range requests here, only current value requests
+  TU_VERIFY(p_request->bRequest == AUDIO_CS_REQ_CUR);
+
+  // Page 91 in UAC2 specification
+  uint8_t channelNum = TU_U16_LOW(p_request->wValue);
+  uint8_t ctrlSel = TU_U16_HIGH(p_request->wValue);
+  uint8_t itf = TU_U16_LOW(p_request->wIndex);
+
+  (void) channelNum; (void) ctrlSel; (void) itf;
+
+  return false; 	// Yet not implemented
+}
+
+// Invoked when audio class specific set request received for an entity
+bool tud_audio_set_req_entity_cb(uint8_t rhport, tusb_control_request_t const * p_request, uint8_t *pBuff)
+{
+  (void) rhport;
+
+  // Page 91 in UAC2 specification
+  uint8_t channelNum = TU_U16_LOW(p_request->wValue);
+  uint8_t ctrlSel = TU_U16_HIGH(p_request->wValue);
+  uint8_t itf = TU_U16_LOW(p_request->wIndex);
+  uint8_t entityID = TU_U16_HIGH(p_request->wIndex);
+
+  (void) itf;
+
+  // We do not support any set range requests here, only current value requests
+  TU_VERIFY(p_request->bRequest == AUDIO_CS_REQ_CUR);
+
+  // If request is for our feature unit
+  if ( entityID == 2 )
+  {
+    switch ( ctrlSel )
+    {
+      case AUDIO_FU_CTRL_MUTE:
+        // Request uses format layout 1
+        TU_VERIFY(p_request->wLength == sizeof(audio_control_cur_1_t));
+
+        mute[channelNum] = ((audio_control_cur_1_t*) pBuff)->bCur;
+
+        TU_LOG2("    Set Mute: %d of channel: %u\r\n", mute[channelNum], channelNum);
+
+      return true;
+
+      case AUDIO_FU_CTRL_VOLUME:
+        // Request uses format layout 2
+        TU_VERIFY(p_request->wLength == sizeof(audio_control_cur_2_t));
+
+        volume[channelNum] = ((audio_control_cur_2_t*) pBuff)->bCur;
+
+        TU_LOG2("    Set Volume: %d dB of channel: %u\r\n", volume[channelNum], channelNum);
+
+     return true;
+
+        // Unknown/Unsupported control
+      default:
+        TU_BREAKPOINT();
+      return false;
+    }
+  }
+  return false;    // Yet not implemented
+}
+
+// Invoked when audio class specific get request received for an EP
+bool tud_audio_get_req_ep_cb(uint8_t rhport, tusb_control_request_t const * p_request)
+{
+  (void) rhport;
+
+  // Page 91 in UAC2 specification
+  uint8_t channelNum = TU_U16_LOW(p_request->wValue);
+  uint8_t ctrlSel = TU_U16_HIGH(p_request->wValue);
+  uint8_t ep = TU_U16_LOW(p_request->wIndex);
+
+  (void) channelNum; (void) ctrlSel; (void) ep;
+
+  //	return tud_control_xfer(rhport, p_request, &tmp, 1);
+
+  return false; 	// Yet not implemented
+}
+
+// Invoked when audio class specific get request received for an interface
+bool tud_audio_get_req_itf_cb(uint8_t rhport, tusb_control_request_t const * p_request)
+{
+  (void) rhport;
+
+  // Page 91 in UAC2 specification
+  uint8_t channelNum = TU_U16_LOW(p_request->wValue);
+  uint8_t ctrlSel = TU_U16_HIGH(p_request->wValue);
+  uint8_t itf = TU_U16_LOW(p_request->wIndex);
+
+  (void) channelNum; (void) ctrlSel; (void) itf;
+
+  return false; 	// Yet not implemented
+}
+
+// Invoked when audio class specific get request received for an entity
+bool tud_audio_get_req_entity_cb(uint8_t rhport, tusb_control_request_t const * p_request)
+{
+  (void) rhport;
+
+  // Page 91 in UAC2 specification
+  uint8_t channelNum = TU_U16_LOW(p_request->wValue);
+  uint8_t ctrlSel = TU_U16_HIGH(p_request->wValue);
+  // uint8_t itf = TU_U16_LOW(p_request->wIndex); 			// Since we have only one audio function implemented, we do not need the itf value
+  uint8_t entityID = TU_U16_HIGH(p_request->wIndex);
+
+  // Input terminal (Microphone input)
+  if (entityID == 1)
+  {
+    switch (ctrlSel)
+    {
+      case AUDIO_TE_CTRL_CONNECTOR:;
+      // The terminal connector control only has a get request with only the CUR attribute.
+
+      audio_desc_channel_cluster_t ret;
+
+      // Those are dummy values for now
+      ret.bNrChannels = 1;
+      ret.bmChannelConfig = 0;
+      ret.iChannelNames = 0;
+
+      TU_LOG2("    Get terminal connector\r\n");
+
+      return tud_audio_buffer_and_schedule_control_xfer(rhport, p_request, (void*)&ret, sizeof(ret));
+
+      // Unknown/Unsupported control selector
+      default: TU_BREAKPOINT(); return false;
+    }
+  }
+
+  // Feature unit
+  if (entityID == 2)
+  {
+    switch (ctrlSel)
+    {
+      case AUDIO_FU_CTRL_MUTE:
+	// Audio control mute cur parameter block consists of only one byte - we thus can send it right away
+	// There does not exist a range parameter block for mute
+	TU_LOG2("    Get Mute of channel: %u\r\n", channelNum);
+	return tud_control_xfer(rhport, p_request, &mute[channelNum], 1);
+
+      case AUDIO_FU_CTRL_VOLUME:
+
+	switch (p_request->bRequest)
+	{
+	  case AUDIO_CS_REQ_CUR:
+	    TU_LOG2("    Get Volume of channel: %u\r\n", channelNum);
+	    return tud_control_xfer(rhport, p_request, &volume[channelNum], sizeof(volume[channelNum]));
+	  case AUDIO_CS_REQ_RANGE:
+	    TU_LOG2("    Get Volume range of channel: %u\r\n", channelNum);
+
+	    // Copy values - only for testing - better is version below
+	    audio_control_range_2_n_t(1) ret;
+
+	    ret.wNumSubRanges = 1;
+	    ret.subrange[0].bMin = -90; 	// -90 dB
+	    ret.subrange[0].bMax = 90;		// +90 dB
+	    ret.subrange[0].bRes = 1; 		// 1 dB steps
+
+	    return tud_audio_buffer_and_schedule_control_xfer(rhport, p_request, (void*)&ret, sizeof(ret));
+
+	    // Unknown/Unsupported control
+	  default: TU_BREAKPOINT(); return false;
+	}
+
+	// Unknown/Unsupported control
+	  default: TU_BREAKPOINT(); return false;
+    }
+  }
+
+  // Clock Source unit
+  if (entityID == 4)
+  {
+    switch (ctrlSel)
+    {
+      case AUDIO_CS_CTRL_SAM_FREQ:
+
+	// channelNum is always zero in this case
+
+	switch (p_request->bRequest)
+	{
+	  case AUDIO_CS_REQ_CUR:
+	    TU_LOG2("    Get Sample Freq.\r\n");
+	    return tud_control_xfer(rhport, p_request, &sampFreq, sizeof(sampFreq));
+	  case AUDIO_CS_REQ_RANGE:
+	    TU_LOG2("    Get Sample Freq. range\r\n");
+	    return tud_control_xfer(rhport, p_request, &sampleFreqRng, sizeof(sampleFreqRng));
+
+	    // Unknown/Unsupported control
+	  default: TU_BREAKPOINT(); return false;
+	}
+
+	  case AUDIO_CS_CTRL_CLK_VALID:
+	    // Only cur attribute exists for this request
+	    TU_LOG2("    Get Sample Freq. valid\r\n");
+	    return tud_control_xfer(rhport, p_request, &clkValid, sizeof(clkValid));
+
+	    // Unknown/Unsupported control
+	  default: TU_BREAKPOINT(); return false;
+    }
+  }
+
+  TU_LOG2("  Unsupported entity: %d\r\n", entityID);
+  return false; 	// Yet not implemented
+}
+
+bool tud_audio_tx_done_pre_load_cb(uint8_t rhport, uint8_t itf, uint8_t ep_in, uint8_t cur_alt_setting)
+{
+  (void) rhport;
+  (void) itf;
+  (void) ep_in;
+  (void) cur_alt_setting;
+
+  tud_audio_write ((uint8_t *)test_buffer_audio, CFG_TUD_AUDIO_TX_FIFO_SIZE);
+
+  return true;
+}
+
+bool tud_audio_tx_done_post_load_cb(uint8_t rhport, uint16_t n_bytes_copied, uint8_t itf, uint8_t ep_in, uint8_t cur_alt_setting)
+{
+  (void) rhport;
+  (void) n_bytes_copied;
+  (void) itf;
+  (void) ep_in;
+  (void) cur_alt_setting;
+
+  for (size_t cnt = 0; cnt < CFG_TUD_AUDIO_TX_FIFO_SIZE/2; cnt++)
+  {
+    test_buffer_audio[cnt] = startVal++;
+  }
+
+  return true;
+}
+
+bool tud_audio_set_itf_close_EP_cb(uint8_t rhport, tusb_control_request_t const * p_request)
+{
+  (void) rhport;
+  (void) p_request;
+  startVal = 0;
+
+  return true;
+}
+
+//--------------------------------------------------------------------+
+// BLINKING TASK
+//--------------------------------------------------------------------+
+void led_blinking_task(void)
+{
+  static uint32_t start_ms = 0;
+  static bool led_state = false;
+
+  // Blink every interval ms
+  if ( board_millis() - start_ms < blink_interval_ms) return; // not enough time
+  start_ms += blink_interval_ms;
+
+  board_led_write(led_state);
+  led_state = 1 - led_state; // toggle
+}
diff --git a/examples/device/audio_test/src/tusb_config.h b/examples/device/audio_test/src/tusb_config.h
new file mode 100644
index 000000000..5d94858ea
--- /dev/null
+++ b/examples/device/audio_test/src/tusb_config.h
@@ -0,0 +1,116 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#ifndef _TUSB_CONFIG_H_
+#define _TUSB_CONFIG_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//--------------------------------------------------------------------
+// COMMON CONFIGURATION
+//--------------------------------------------------------------------
+
+// defined by compiler flags for flexibility
+#ifndef CFG_TUSB_MCU
+#error CFG_TUSB_MCU must be defined
+#endif
+
+#if CFG_TUSB_MCU == OPT_MCU_LPC43XX || CFG_TUSB_MCU == OPT_MCU_LPC18XX || CFG_TUSB_MCU == OPT_MCU_MIMXRT10XX
+#define CFG_TUSB_RHPORT0_MODE       (OPT_MODE_DEVICE | OPT_MODE_HIGH_SPEED)
+#else
+#define CFG_TUSB_RHPORT0_MODE       OPT_MODE_DEVICE
+#endif
+
+#define CFG_TUSB_OS                 OPT_OS_NONE
+
+#ifndef CFG_TUSB_DEBUG
+#define CFG_TUSB_DEBUG              0
+#endif
+
+// CFG_TUSB_DEBUG is defined by compiler in DEBUG build
+// #define CFG_TUSB_DEBUG           0
+
+/* USB DMA on some MCUs can only access a specific SRAM region with restriction on alignment.
+ * Tinyusb use follows macros to declare transferring memory so that they can be put
+ * into those specific section.
+ * e.g
+ * - CFG_TUSB_MEM SECTION : __attribute__ (( section(".usb_ram") ))
+ * - CFG_TUSB_MEM_ALIGN   : __attribute__ ((aligned(4)))
+ */
+#ifndef CFG_TUSB_MEM_SECTION
+#define CFG_TUSB_MEM_SECTION
+#endif
+
+#ifndef CFG_TUSB_MEM_ALIGN
+#define CFG_TUSB_MEM_ALIGN          __attribute__ ((aligned(4)))
+#endif
+
+//--------------------------------------------------------------------
+// DEVICE CONFIGURATION
+//--------------------------------------------------------------------
+
+#ifndef CFG_TUD_ENDPOINT0_SIZE
+#define CFG_TUD_ENDPOINT0_SIZE    64
+#endif
+
+//------------- CLASS -------------//
+#define CFG_TUD_CDC               0
+#define CFG_TUD_MSC               0
+#define CFG_TUD_HID               0
+#define CFG_TUD_MIDI              0
+#define CFG_TUD_AUDIO             1
+#define CFG_TUD_VENDOR            0
+
+//--------------------------------------------------------------------
+// AUDIO CLASS DRIVER CONFIGURATION
+//--------------------------------------------------------------------
+
+// Audio format type
+#define CFG_TUD_AUDIO_USE_TX_FIFO 				1
+#define CFG_TUD_AUDIO_FORMAT_TYPE_TX 				AUDIO_FORMAT_TYPE_I
+#define CFG_TUD_AUDIO_FORMAT_TYPE_RX 				AUDIO_FORMAT_TYPE_UNDEFINED
+
+// Audio format type I specifications
+#define CFG_TUD_AUDIO_FORMAT_TYPE_I_TX 				AUDIO_DATA_FORMAT_TYPE_I_PCM
+#define CFG_TUD_AUDIO_N_CHANNELS_TX 				1
+#define CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX			2
+
+// EP and buffer size - for isochronous EP´s, the buffer and EP size are equal (different sizes would not make sense)
+#define CFG_TUD_AUDIO_EPSIZE_IN                                       48*CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX*CFG_TUD_AUDIO_N_CHANNELS_TX    // 48 Samples (48 kHz) x 2 Bytes/Sample x 1 Channels
+#define CFG_TUD_AUDIO_TX_FIFO_SIZE                                    48*2                                                                  // 48 Samples (48 kHz) x 2 Bytes/Sample (1/2 word)
+
+// Number of Standard AS Interface Descriptors (4.9.1) defined per audio function - this is required to be able to remember the current alternate settings of these interfaces - We restrict us here to have a constant number for all audio functions (which means this has to be the maximum number of AS interfaces an audio function has and a second audio function with less AS interfaces just wastes a few bytes)
+#define CFG_TUD_AUDIO_N_AS_INT 			          1
+
+// Size of control request buffer
+#define CFG_TUD_AUDIO_CTRL_BUF_SIZE 				64
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _TUSB_CONFIG_H_ */
diff --git a/examples/device/audio_test/src/usb_descriptors.c b/examples/device/audio_test/src/usb_descriptors.c
new file mode 100644
index 000000000..02d018823
--- /dev/null
+++ b/examples/device/audio_test/src/usb_descriptors.c
@@ -0,0 +1,167 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#include "tusb.h"
+
+/* A combination of interfaces must have a unique product id, since PC will save device driver after the first plug.
+ * Same VID/PID with different interface e.g MSC (first), then CDC (later) will possibly cause system error on PC.
+ *
+ * Auto ProductID layout's Bitmap:
+ *   [MSB]     AUDIO | MIDI | HID | MSC | CDC          [LSB]
+ */
+#define _PID_MAP(itf, n)  ( (CFG_TUD_##itf) << (n) )
+#define USB_PID           (0x4000 | _PID_MAP(CDC, 0) | _PID_MAP(MSC, 1) | _PID_MAP(HID, 2) | \
+    _PID_MAP(MIDI, 3) | _PID_MAP(AUDIO, 4) | _PID_MAP(VENDOR, 5) )
+
+//--------------------------------------------------------------------+
+// Device Descriptors
+//--------------------------------------------------------------------+
+tusb_desc_device_t const desc_device =
+{
+    .bLength            = sizeof(tusb_desc_device_t),
+    .bDescriptorType    = TUSB_DESC_DEVICE,
+    .bcdUSB             = 0x0200,
+
+    // Use Interface Association Descriptor (IAD) for CDC
+    // As required by USB Specs IAD's subclass must be common class (2) and protocol must be IAD (1)
+    .bDeviceClass       = TUSB_CLASS_MISC,
+    .bDeviceSubClass    = MISC_SUBCLASS_COMMON,
+    .bDeviceProtocol    = MISC_PROTOCOL_IAD,
+    .bMaxPacketSize0    = CFG_TUD_ENDPOINT0_SIZE,
+
+    .idVendor           = 0xCafe,
+    .idProduct          = USB_PID,
+    .bcdDevice          = 0x0100,
+
+    .iManufacturer      = 0x01,
+    .iProduct           = 0x02,
+    .iSerialNumber      = 0x03,
+
+    .bNumConfigurations = 0x01
+};
+
+// Invoked when received GET DEVICE DESCRIPTOR
+// Application return pointer to descriptor
+uint8_t const * tud_descriptor_device_cb(void)
+{
+  return (uint8_t const *) &desc_device;
+}
+
+//--------------------------------------------------------------------+
+// Configuration Descriptor
+//--------------------------------------------------------------------+
+enum
+{
+  ITF_NUM_AUDIO_CONTROL = 0,
+  ITF_NUM_AUDIO_STREAMING,
+  ITF_NUM_TOTAL
+};
+
+#define CONFIG_TOTAL_LEN    	(TUD_CONFIG_DESC_LEN + CFG_TUD_AUDIO * TUD_AUDIO_MIC_DESC_LEN)
+
+#if CFG_TUSB_MCU == OPT_MCU_LPC175X_6X || CFG_TUSB_MCU == OPT_MCU_LPC177X_8X || CFG_TUSB_MCU == OPT_MCU_LPC40XX
+// LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
+// 0 control, 1 In, 2 Bulk, 3 Iso, 4 In etc ...
+#define EPNUM_AUDIO   0x03
+#else
+#define EPNUM_AUDIO   0x01
+#endif
+
+// These variables are required by the audio driver in audio_device.c
+
+// List of audio descriptor lengths which is required by audio driver - you need as many entries as CFG_TUD_AUDIO - unfortunately this is not possible to determine otherwise
+const uint16_t tud_audio_desc_lengths[] = {TUD_AUDIO_MIC_DESC_LEN};
+
+// TAKE CARE - THE NUMBER OF AUDIO STREAMING INTERFACES PER AUDIO FUNCTION MUST NOT EXCEED CFG_TUD_AUDIO_N_AS_INT - IF IT DOES INCREASE CFG_TUD_AUDIO_N_AS_INT IN tusb_config.h!
+
+uint8_t const desc_configuration[] =
+{
+    // Interface count, string index, total length, attribute, power in mA
+    TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP, 100),
+
+    // Interface number, string index, EP Out & EP In address, EP size
+    TUD_AUDIO_MIC_DESCRIPTOR(/*_itfnum*/ ITF_NUM_AUDIO_CONTROL, /*_stridx*/ 0, /*_nBytesPerSample*/ 3, /*_nBitsUsedPerSample*/ 24, /*_epin*/ 0x80 | EPNUM_AUDIO, /*_epsize*/ 48*4)
+};
+
+// Invoked when received GET CONFIGURATION DESCRIPTOR
+// Application return pointer to descriptor
+// Descriptor contents must exist long enough for transfer to complete
+uint8_t const * tud_descriptor_configuration_cb(uint8_t index)
+{
+  (void) index; // for multiple configurations
+  return desc_configuration;
+}
+
+//--------------------------------------------------------------------+
+// String Descriptors
+//--------------------------------------------------------------------+
+
+// array of pointer to string descriptors
+char const* string_desc_arr [] =
+{
+    (const char[]) { 0x09, 0x04 }, 	// 0: is supported language is English (0x0409)
+    "PaniRCorp",                   	// 1: Manufacturer
+    "MicNode",              		// 2: Product
+    "123456",                      	// 3: Serials, should use chip ID
+    "UAC2",                 	 	// 4: Audio Interface
+};
+
+static uint16_t _desc_str[32];
+
+// Invoked when received GET STRING DESCRIPTOR request
+// Application return pointer to descriptor, whose contents must exist long enough for transfer to complete
+uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid)
+{
+  (void) langid;
+
+  uint8_t chr_count;
+
+  if ( index == 0)
+  {
+    memcpy(&_desc_str[1], string_desc_arr[0], 2);
+    chr_count = 1;
+  }else
+  {
+    // Convert ASCII string into UTF-16
+
+    if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) return NULL;
+
+    const char* str = string_desc_arr[index];
+
+    // Cap at max char
+    chr_count = strlen(str);
+    if ( chr_count > 31 ) chr_count = 31;
+
+    for(uint8_t i=0; i<chr_count; i++)
+    {
+      _desc_str[1+i] = str[i];
+    }
+  }
+
+  // first byte is length (including header), second byte is string type
+  _desc_str[0] = (TUSB_DESC_STRING << 8 ) | (2*chr_count + 2);
+
+  return _desc_str;
+}
diff --git a/examples/device/hid_multiple_interface/Makefile b/examples/device/hid_multiple_interface/Makefile
new file mode 100644
index 000000000..69b633fea
--- /dev/null
+++ b/examples/device/hid_multiple_interface/Makefile
@@ -0,0 +1,12 @@
+include ../../../tools/top.mk
+include ../../make.mk
+
+INC += \
+	src \
+	$(TOP)/hw \
+
+# Example source
+EXAMPLE_SOURCE += $(wildcard src/*.c)
+SRC_C += $(addprefix $(CURRENT_PATH)/, $(EXAMPLE_SOURCE))
+
+include ../../rules.mk
diff --git a/examples/device/hid_multiple_interface/src/main.c b/examples/device/hid_multiple_interface/src/main.c
new file mode 100644
index 000000000..7cb1d75a7
--- /dev/null
+++ b/examples/device/hid_multiple_interface/src/main.c
@@ -0,0 +1,207 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "bsp/board.h"
+#include "tusb.h"
+
+//--------------------------------------------------------------------+
+// MACRO CONSTANT TYPEDEF PROTYPES
+//--------------------------------------------------------------------+
+
+// Interface index depends on the order in configuration descriptor
+enum {
+  ITF_KEYBOARD = 0,
+  ITF_MOUSE = 1
+};
+
+/* Blink pattern
+ * - 250 ms  : device not mounted
+ * - 1000 ms : device mounted
+ * - 2500 ms : device is suspended
+ */
+enum  {
+  BLINK_NOT_MOUNTED = 250,
+  BLINK_MOUNTED = 1000,
+  BLINK_SUSPENDED = 2500,
+};
+
+static uint32_t blink_interval_ms = BLINK_NOT_MOUNTED;
+
+void led_blinking_task(void);
+void hid_task(void);
+
+/*------------- MAIN -------------*/
+int main(void)
+{
+  board_init();
+  tusb_init();
+
+  while (1)
+  {
+    tud_task(); // tinyusb device task
+    led_blinking_task();
+
+    hid_task();
+  }
+
+  return 0;
+}
+
+//--------------------------------------------------------------------+
+// Device callbacks
+//--------------------------------------------------------------------+
+
+// Invoked when device is mounted
+void tud_mount_cb(void)
+{
+  blink_interval_ms = BLINK_MOUNTED;
+}
+
+// Invoked when device is unmounted
+void tud_umount_cb(void)
+{
+  blink_interval_ms = BLINK_NOT_MOUNTED;
+}
+
+// Invoked when usb bus is suspended
+// remote_wakeup_en : if host allow us  to perform remote wakeup
+// Within 7ms, device must draw an average of current less than 2.5 mA from bus
+void tud_suspend_cb(bool remote_wakeup_en)
+{
+  (void) remote_wakeup_en;
+  blink_interval_ms = BLINK_SUSPENDED;
+}
+
+// Invoked when usb bus is resumed
+void tud_resume_cb(void)
+{
+  blink_interval_ms = BLINK_MOUNTED;
+}
+
+//--------------------------------------------------------------------+
+// USB HID
+//--------------------------------------------------------------------+
+
+void hid_task(void)
+{
+  // Poll every 10ms
+  const uint32_t interval_ms = 10;
+  static uint32_t start_ms = 0;
+
+  if ( board_millis() - start_ms < interval_ms) return; // not enough time
+  start_ms += interval_ms;
+
+  uint32_t const btn = board_button_read();
+
+  // Remote wakeup
+  if ( tud_suspended() && btn )
+  {
+    // Wake up host if we are in suspend mode
+    // and REMOTE_WAKEUP feature is enabled by host
+    tud_remote_wakeup();
+  }
+
+  /*------------- Keyboard -------------*/
+  if ( tud_hid_n_ready(ITF_KEYBOARD) )
+  {
+    // use to avoid send multiple consecutive zero report for keyboard
+    static bool has_key = false;
+
+    if ( btn )
+    {
+      uint8_t keycode[6] = { 0 };
+      keycode[0] = HID_KEY_A;
+
+      tud_hid_n_keyboard_report(ITF_KEYBOARD, 0, 0, keycode);
+
+      has_key = true;
+    }else
+    {
+      // send empty key report if previously has key pressed
+      if (has_key) tud_hid_n_keyboard_report(ITF_KEYBOARD, 0, 0, NULL);
+      has_key = false;
+    }
+  }
+
+  /*------------- Mouse -------------*/
+  if ( tud_hid_n_ready(ITF_MOUSE) )
+  {
+    if ( btn )
+    {
+      int8_t const delta = 5;
+
+      // no button, right + down, no scroll pan
+      tud_hid_n_mouse_report(ITF_MOUSE, 0, 0x00, delta, delta, 0, 0);
+    }
+  }
+}
+
+
+// Invoked when received GET_REPORT control request
+// Application must fill buffer report's content and return its length.
+// Return zero will cause the stack to STALL request
+uint16_t tud_hid_get_report_cb(uint8_t itf, uint8_t report_id, hid_report_type_t report_type, uint8_t* buffer, uint16_t reqlen)
+{
+  // TODO not Implemented
+  (void) itf;
+  (void) report_id;
+  (void) report_type;
+  (void) buffer;
+  (void) reqlen;
+
+  return 0;
+}
+
+// Invoked when received SET_REPORT control request or
+// received data on OUT endpoint ( Report ID = 0, Type = 0 )
+void tud_hid_set_report_cb(uint8_t itf, uint8_t report_id, hid_report_type_t report_type, uint8_t const* buffer, uint16_t bufsize)
+{
+  // TODO set LED based on CAPLOCK, NUMLOCK etc...
+  (void) itf;
+  (void) report_id;
+  (void) report_type;
+  (void) buffer;
+  (void) bufsize;
+}
+
+//--------------------------------------------------------------------+
+// BLINKING TASK
+//--------------------------------------------------------------------+
+void led_blinking_task(void)
+{
+  static uint32_t start_ms = 0;
+  static bool led_state = false;
+
+  // Blink every interval ms
+  if ( board_millis() - start_ms < blink_interval_ms) return; // not enough time
+  start_ms += blink_interval_ms;
+
+  board_led_write(led_state);
+  led_state = 1 - led_state; // toggle
+}
diff --git a/examples/device/hid_multiple_interface/src/tusb_config.h b/examples/device/hid_multiple_interface/src/tusb_config.h
new file mode 100644
index 000000000..412f9b004
--- /dev/null
+++ b/examples/device/hid_multiple_interface/src/tusb_config.h
@@ -0,0 +1,110 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#ifndef _TUSB_CONFIG_H_
+#define _TUSB_CONFIG_H_
+
+#ifdef __cplusplus
+ extern "C" {
+#endif
+
+//--------------------------------------------------------------------
+// COMMON CONFIGURATION
+//--------------------------------------------------------------------
+
+// defined by board.mk
+#ifndef CFG_TUSB_MCU
+  #error CFG_TUSB_MCU must be defined
+#endif
+
+// RHPort number used for device can be defined by board.mk, default to port 0
+#ifndef BOARD_DEVICE_RHPORT_NUM
+  #define BOARD_DEVICE_RHPORT_NUM     0
+#endif
+
+// RHPort max operational speed can defined by board.mk
+// Default to Highspeed for MCU with internal HighSpeed PHY (can be port specific), otherwise FullSpeed
+#ifndef BOARD_DEVICE_RHPORT_SPEED
+  #if (CFG_TUSB_MCU == OPT_MCU_LPC18XX || CFG_TUSB_MCU == OPT_MCU_LPC43XX || CFG_TUSB_MCU == OPT_MCU_MIMXRT10XX || \
+       CFG_TUSB_MCU == OPT_MCU_NUC505  || CFG_TUSB_MCU == OPT_MCU_CXD56)
+    #define BOARD_DEVICE_RHPORT_SPEED   OPT_MODE_HIGH_SPEED
+  #else
+    #define BOARD_DEVICE_RHPORT_SPEED   OPT_MODE_FULL_SPEED
+  #endif
+#endif
+
+// Device mode with rhport and speed defined by board.mk
+#if   BOARD_DEVICE_RHPORT_NUM == 0
+  #define CFG_TUSB_RHPORT0_MODE     (OPT_MODE_DEVICE | BOARD_DEVICE_RHPORT_SPEED)
+#elif BOARD_DEVICE_RHPORT_NUM == 1
+  #define CFG_TUSB_RHPORT1_MODE     (OPT_MODE_DEVICE | BOARD_DEVICE_RHPORT_SPEED)
+#else
+  #error "Incorrect RHPort configuration"
+#endif
+
+// This example doesn't use an RTOS
+#define CFG_TUSB_OS               OPT_OS_NONE
+
+// CFG_TUSB_DEBUG is defined by compiler in DEBUG build
+// #define CFG_TUSB_DEBUG           0
+
+/* USB DMA on some MCUs can only access a specific SRAM region with restriction on alignment.
+ * Tinyusb use follows macros to declare transferring memory so that they can be put
+ * into those specific section.
+ * e.g
+ * - CFG_TUSB_MEM SECTION : __attribute__ (( section(".usb_ram") ))
+ * - CFG_TUSB_MEM_ALIGN   : __attribute__ ((aligned(4)))
+ */
+#ifndef CFG_TUSB_MEM_SECTION
+#define CFG_TUSB_MEM_SECTION
+#endif
+
+#ifndef CFG_TUSB_MEM_ALIGN
+#define CFG_TUSB_MEM_ALIGN          __attribute__ ((aligned(4)))
+#endif
+
+//--------------------------------------------------------------------
+// DEVICE CONFIGURATION
+//--------------------------------------------------------------------
+
+#ifndef CFG_TUD_ENDPOINT0_SIZE
+#define CFG_TUD_ENDPOINT0_SIZE    64
+#endif
+
+//------------- CLASS -------------//
+#define CFG_TUD_HID               2
+#define CFG_TUD_CDC               0
+#define CFG_TUD_MSC               0
+#define CFG_TUD_MIDI              0
+#define CFG_TUD_VENDOR            0
+
+// HID buffer size Should be sufficient to hold ID (if any) + Data
+#define CFG_TUD_HID_EP_BUFSIZE    8
+
+#ifdef __cplusplus
+ }
+#endif
+
+#endif /* _TUSB_CONFIG_H_ */
diff --git a/examples/device/hid_multiple_interface/src/usb_descriptors.c b/examples/device/hid_multiple_interface/src/usb_descriptors.c
new file mode 100644
index 000000000..0d67d499a
--- /dev/null
+++ b/examples/device/hid_multiple_interface/src/usb_descriptors.c
@@ -0,0 +1,188 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Ha Thach (tinyusb.org)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#include "tusb.h"
+
+/* A combination of interfaces must have a unique product id, since PC will save device driver after the first plug.
+ * Same VID/PID with different interface e.g MSC (first), then CDC (later) will possibly cause system error on PC.
+ *
+ * Auto ProductID layout's Bitmap:
+ *   [MSB]         HID | MSC | CDC          [LSB]
+ */
+#define _PID_MAP(itf, n)  ( (CFG_TUD_##itf) << (n) )
+#define USB_PID           (0x4000 | _PID_MAP(CDC, 0) | _PID_MAP(MSC, 1) | _PID_MAP(HID, 2) | \
+                           _PID_MAP(MIDI, 3) | _PID_MAP(VENDOR, 4) )
+
+//--------------------------------------------------------------------+
+// Device Descriptors
+//--------------------------------------------------------------------+
+tusb_desc_device_t const desc_device =
+{
+    .bLength            = sizeof(tusb_desc_device_t),
+    .bDescriptorType    = TUSB_DESC_DEVICE,
+    .bcdUSB             = 0x0200,
+    .bDeviceClass       = 0x00,
+    .bDeviceSubClass    = 0x00,
+    .bDeviceProtocol    = 0x00,
+    .bMaxPacketSize0    = CFG_TUD_ENDPOINT0_SIZE,
+
+    .idVendor           = 0xCafe,
+    .idProduct          = USB_PID,
+    .bcdDevice          = 0x0100,
+
+    .iManufacturer      = 0x01,
+    .iProduct           = 0x02,
+    .iSerialNumber      = 0x03,
+
+    .bNumConfigurations = 0x01
+};
+
+// Invoked when received GET DEVICE DESCRIPTOR
+// Application return pointer to descriptor
+uint8_t const * tud_descriptor_device_cb(void)
+{
+  return (uint8_t const *) &desc_device;
+}
+
+//--------------------------------------------------------------------+
+// HID Report Descriptor
+//--------------------------------------------------------------------+
+
+uint8_t const desc_hid_report1[] =
+{
+  TUD_HID_REPORT_DESC_KEYBOARD()
+};
+
+uint8_t const desc_hid_report2[] =
+{
+  TUD_HID_REPORT_DESC_MOUSE()
+};
+
+// Invoked when received GET HID REPORT DESCRIPTOR
+// Application return pointer to descriptor
+// Descriptor contents must exist long enough for transfer to complete
+uint8_t const * tud_hid_descriptor_report_cb(uint8_t itf)
+{
+  if (itf == 0)
+  {
+    return desc_hid_report1;
+  }
+  else if (itf == 1)
+  {
+    return desc_hid_report2;
+  }
+
+  return NULL;
+}
+
+//--------------------------------------------------------------------+
+// Configuration Descriptor
+//--------------------------------------------------------------------+
+
+enum
+{
+  ITF_NUM_HID1,
+  ITF_NUM_HID2,
+  ITF_NUM_TOTAL
+};
+
+#define  CONFIG_TOTAL_LEN  (TUD_CONFIG_DESC_LEN + TUD_HID_DESC_LEN + TUD_HID_DESC_LEN)
+
+#define EPNUM_HID1   0x81
+#define EPNUM_HID2   0x82
+
+uint8_t const desc_configuration[] =
+{
+  // Config number, interface count, string index, total length, attribute, power in mA
+  TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP, 100),
+
+  // Interface number, string index, protocol, report descriptor len, EP In & Out address, size & polling interval
+  TUD_HID_DESCRIPTOR(ITF_NUM_HID1, 4, HID_PROTOCOL_NONE, sizeof(desc_hid_report1), EPNUM_HID1, CFG_TUD_HID_EP_BUFSIZE, 10),
+  TUD_HID_DESCRIPTOR(ITF_NUM_HID2, 5, HID_PROTOCOL_NONE, sizeof(desc_hid_report2), EPNUM_HID2, CFG_TUD_HID_EP_BUFSIZE, 10)
+};
+
+// Invoked when received GET CONFIGURATION DESCRIPTOR
+// Application return pointer to descriptor
+// Descriptor contents must exist long enough for transfer to complete
+uint8_t const * tud_descriptor_configuration_cb(uint8_t index)
+{
+  (void) index; // for multiple configurations
+  return desc_configuration;
+}
+
+//--------------------------------------------------------------------+
+// String Descriptors
+//--------------------------------------------------------------------+
+
+// array of pointer to string descriptors
+char const* string_desc_arr [] =
+{
+  (const char[]) { 0x09, 0x04 },  // 0: is supported language is English (0x0409)
+  "TinyUSB",                              // 1: Manufacturer
+  "TinyUSB Device",                 // 2: Product
+  "123456",                                // 3: Serials, should use chip ID
+  "Keyboard Interface",             // 4: Interface 1 String
+  "Mouse Interface",                 // 5: Interface 2 String
+};
+
+static uint16_t _desc_str[32];
+
+// Invoked when received GET STRING DESCRIPTOR request
+// Application return pointer to descriptor, whose contents must exist long enough for transfer to complete
+uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid)
+{
+  (void) langid;
+
+  uint8_t chr_count;
+
+  if ( index == 0)
+  {
+    memcpy(&_desc_str[1], string_desc_arr[0], 2);
+    chr_count = 1;
+  }else
+  {
+    // Note: the 0xEE index string is a Microsoft OS 1.0 Descriptors.
+    // https://docs.microsoft.com/en-us/windows-hardware/drivers/usbcon/microsoft-defined-usb-descriptors
+
+    if ( !(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0])) ) return NULL;
+
+    const char* str = string_desc_arr[index];
+
+    // Cap at max char
+    chr_count = strlen(str);
+    if ( chr_count > 31 ) chr_count = 31;
+
+    // Convert ASCII string into UTF-16
+    for(uint8_t i=0; i<chr_count; i++)
+    {
+      _desc_str[1+i] = str[i];
+    }
+  }
+
+  // first byte is length (including header), second byte is string type
+  _desc_str[0] = (TUSB_DESC_STRING << 8 ) | (2*chr_count + 2);
+
+  return _desc_str;
+}
diff --git a/examples/device/net_lwip_webserver/src/lwipopts.h b/examples/device/net_lwip_webserver/src/lwipopts.h
index 23319592d..5a8096f50 100644
--- a/examples/device/net_lwip_webserver/src/lwipopts.h
+++ b/examples/device/net_lwip_webserver/src/lwipopts.h
@@ -35,7 +35,7 @@
 /* Prevent having to link sys_arch.c (we don't test the API layers in unit tests) */
 #define NO_SYS                          1
 #define MEM_ALIGNMENT                   4
-#define LWIP_RAW                        1
+#define LWIP_RAW                        0
 #define LWIP_NETCONN                    0
 #define LWIP_SOCKET                     0
 #define LWIP_DHCP                       0
@@ -54,4 +54,6 @@
 #define LWIP_HTTPD_SSI                  0
 #define LWIP_HTTPD_SSI_INCLUDE_TAG      0
 
+#define LWIP_SINGLE_NETIF               1
+
 #endif /* __LWIPOPTS_H__ */
diff --git a/examples/device/net_lwip_webserver/src/main.c b/examples/device/net_lwip_webserver/src/main.c
index b672ca3bb..27adce86f 100644
--- a/examples/device/net_lwip_webserver/src/main.c
+++ b/examples/device/net_lwip_webserver/src/main.c
@@ -32,6 +32,16 @@ RNDIS should be valid on Linux and Windows hosts, and CDC-ECM should be valid on
 
 The MCU appears to the host as IP address 192.168.7.1, and provides a DHCP server, DNS server, and web server.
 */
+/*
+Some smartphones *may* work with this implementation as well, but likely have limited (broken) drivers,
+and likely their manufacturer has not tested such functionality.  Some code workarounds could be tried:
+
+The smartphone may only have an ECM driver, but refuse to automatically pick ECM (unlike the OSes above);
+try modifying ./examples/devices/net_lwip_webserver/usb_descriptors.c so that CONFIG_ID_ECM is default.
+
+The smartphone may be artificially picky about which Ethernet MAC address to recognize; if this happens, 
+try changing the first byte of tud_network_mac_address[] below from 0x02 to 0x00 (clearing bit 1).
+*/
 
 #include "bsp/board.h"
 #include "tusb.h"
@@ -50,7 +60,7 @@ static struct pbuf *received_frame;
 
 /* this is used by this code, ./class/net/net_driver.c, and usb_descriptors.c */
 /* ideally speaking, this should be generated from the hardware's unique ID (if available) */
-/* it is suggested that the first two bytes are 0x02,0x02 to indicate a link-local address */
+/* it is suggested that the first byte is 0x02 to indicate a link-local address */
 const uint8_t tud_network_mac_address[6] = {0x02,0x02,0x84,0x6A,0x96,0x00};
 
 /* network parameters of this MCU */
@@ -61,22 +71,21 @@ static const ip_addr_t gateway = IPADDR4_INIT_BYTES(0, 0, 0, 0);
 /* database IP addresses that can be offered to the host; this must be in RAM to store assigned MAC addresses */
 static dhcp_entry_t entries[] =
 {
-  /* mac    ip address        subnet mask        lease time */
-  { {0}, {192, 168, 7, 2}, {255, 255, 255, 0}, 24 * 60 * 60 },
-  { {0}, {192, 168, 7, 3}, {255, 255, 255, 0}, 24 * 60 * 60 },
-  { {0}, {192, 168, 7, 4}, {255, 255, 255, 0}, 24 * 60 * 60 }
+    /* mac ip address                          lease time */
+    { {0}, IPADDR4_INIT_BYTES(192, 168, 7, 2), 24 * 60 * 60 },
+    { {0}, IPADDR4_INIT_BYTES(192, 168, 7, 3), 24 * 60 * 60 },
+    { {0}, IPADDR4_INIT_BYTES(192, 168, 7, 4), 24 * 60 * 60 },
 };
 
-/* DHCP configuration parameters, leveraging "entries" above */
 static const dhcp_config_t dhcp_config =
 {
-  {192, 168, 7, 1}, 67,    /* server address (self), port */
-  {192, 168, 7, 1},        /* dns server (self) */
-  "usb",                   /* dns suffix */
-  TU_ARRAY_SIZE(entries),  /* number of entries */
-  entries                  /* pointer to entries */
+    .router = IPADDR4_INIT_BYTES(0, 0, 0, 0),  /* router address (if any) */
+    .port = 67,                                /* listen port */
+    .dns = IPADDR4_INIT_BYTES(192, 168, 7, 1), /* dns server (if any) */
+    "usb",                                     /* dns suffix */
+    TU_ARRAY_SIZE(entries),                    /* num entry */
+    entries                                    /* entries */
 };
-
 static err_t linkoutput_fn(struct netif *netif, struct pbuf *p)
 {
   (void)netif;
@@ -90,7 +99,7 @@ static err_t linkoutput_fn(struct netif *netif, struct pbuf *p)
     /* if the network driver can accept another packet, we make it happen */
     if (tud_network_can_xmit())
     {
-      tud_network_xmit(p);
+      tud_network_xmit(p, 0 /* unused for this example */);
       return ERR_OK;
     }
 
@@ -143,17 +152,49 @@ bool dns_query_proc(const char *name, ip_addr_t *addr)
   return false;
 }
 
-bool tud_network_recv_cb(struct pbuf *p)
+bool tud_network_recv_cb(const uint8_t *src, uint16_t size)
 {
   /* this shouldn't happen, but if we get another packet before 
   parsing the previous, we must signal our inability to accept it */
   if (received_frame) return false;
 
-  /* store away the pointer for service_traffic() to later handle */
-  received_frame = p;
+  if (size)
+  {
+    struct pbuf *p = pbuf_alloc(PBUF_RAW, size, PBUF_POOL);
+
+    if (p)
+    {
+      /* pbuf_alloc() has already initialized struct; all we need to do is copy the data */
+      memcpy(p->payload, src, size);
+
+      /* store away the pointer for service_traffic() to later handle */
+      received_frame = p;
+    }
+  }
+
   return true;
 }
 
+uint16_t tud_network_xmit_cb(uint8_t *dst, void *ref, uint16_t arg)
+{
+  struct pbuf *p = (struct pbuf *)ref;
+  struct pbuf *q;
+  uint16_t len = 0;
+
+  (void)arg; /* unused for this example */
+
+  /* traverse the "pbuf chain"; see ./lwip/src/core/pbuf.c for more info */
+  for(q = p; q != NULL; q = q->next)
+  {
+    memcpy(dst, (char *)q->payload, q->len);
+    dst += q->len;
+    len += q->len;
+    if (q->len == q->tot_len) break;
+  }
+
+  return len;
+}
+
 static void service_traffic(void)
 {
   /* handle any packet received by tud_network_recv_cb() */
diff --git a/examples/device/uac2_headset/Makefile b/examples/device/uac2_headset/Makefile
new file mode 100644
index 000000000..5a455078e
--- /dev/null
+++ b/examples/device/uac2_headset/Makefile
@@ -0,0 +1,12 @@
+include ../../../tools/top.mk
+include ../../make.mk
+
+INC += \
+  src \
+  $(TOP)/hw \
+
+# Example source
+EXAMPLE_SOURCE += $(wildcard src/*.c)
+SRC_C += $(addprefix $(CURRENT_PATH)/, $(EXAMPLE_SOURCE))
+
+include ../../rules.mk
diff --git a/examples/device/uac2_headset/src/main.c b/examples/device/uac2_headset/src/main.c
new file mode 100644
index 000000000..cdb29f3f4
--- /dev/null
+++ b/examples/device/uac2_headset/src/main.c
@@ -0,0 +1,391 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Jerzy Kasenberg
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+
+#include "bsp/board.h"
+#include "tusb.h"
+#include "usb_descriptors.h"
+
+//--------------------------------------------------------------------+
+// MACRO CONSTANT TYPEDEF PROTOTYPES
+//--------------------------------------------------------------------+
+
+/* Blink pattern
+ * - 25 ms   : streaming data
+ * - 250 ms  : device not mounted
+ * - 1000 ms : device mounted
+ * - 2500 ms : device is suspended
+ */
+enum
+{
+  BLINK_STREAMING = 25,
+  BLINK_NOT_MOUNTED = 250,
+  BLINK_MOUNTED = 1000,
+  BLINK_SUSPENDED = 2500,
+};
+
+enum
+{
+  VOLUME_CTRL_0_DB = 0,
+  VOLUME_CTRL_10_DB = 2560,
+  VOLUME_CTRL_20_DB = 5120,
+  VOLUME_CTRL_30_DB = 7680,
+  VOLUME_CTRL_40_DB = 10240,
+  VOLUME_CTRL_50_DB = 12800,
+  VOLUME_CTRL_60_DB = 15360,
+  VOLUME_CTRL_70_DB = 17920,
+  VOLUME_CTRL_80_DB = 20480,
+  VOLUME_CTRL_90_DB = 23040,
+  VOLUME_CTRL_100_DB = 25600,
+  VOLUME_CTRL_SILENCE = 0x8000,
+};
+
+static uint32_t blink_interval_ms = BLINK_NOT_MOUNTED;
+
+// Audio controls
+// Current states
+int8_t mute[CFG_TUD_AUDIO_N_CHANNELS_TX + 1];       // +1 for master channel 0
+int16_t volume[CFG_TUD_AUDIO_N_CHANNELS_TX + 1];    // +1 for master channel 0
+
+// Buffer for microphone data
+int16_t mic_buf[1000];
+// Buffer for speaker data
+int16_t spk_buf[1000];
+// Speaker data size received in the last frame
+int spk_data_size;
+
+void led_blinking_task(void);
+void audio_task(void);
+
+/*------------- MAIN -------------*/
+int main(void)
+{
+  board_init();
+
+  tusb_init();
+
+  TU_LOG1("Headset running\r\n");
+
+  while (1)
+  {
+    tud_task(); // TinyUSB device task
+    audio_task();
+    led_blinking_task();
+  }
+
+  return 0;
+}
+
+//--------------------------------------------------------------------+
+// Device callbacks
+//--------------------------------------------------------------------+
+
+// Invoked when device is mounted
+void tud_mount_cb(void)
+{
+  blink_interval_ms = BLINK_MOUNTED;
+}
+
+// Invoked when device is unmounted
+void tud_umount_cb(void)
+{
+  blink_interval_ms = BLINK_NOT_MOUNTED;
+}
+
+// Invoked when usb bus is suspended
+// remote_wakeup_en : if host allow us  to perform remote wakeup
+// Within 7ms, device must draw an average of current less than 2.5 mA from bus
+void tud_suspend_cb(bool remote_wakeup_en)
+{
+  (void)remote_wakeup_en;
+  blink_interval_ms = BLINK_SUSPENDED;
+}
+
+// Invoked when usb bus is resumed
+void tud_resume_cb(void)
+{
+  blink_interval_ms = BLINK_MOUNTED;
+}
+
+typedef struct TU_ATTR_PACKED
+{
+  union
+  {
+    struct TU_ATTR_PACKED
+    {
+      uint8_t recipient :  5; ///< Recipient type tusb_request_recipient_t.
+      uint8_t type      :  2; ///< Request type tusb_request_type_t.
+      uint8_t direction :  1; ///< Direction type. tusb_dir_t
+    } bmRequestType_bit;
+
+    uint8_t bmRequestType;
+  };
+
+  audio_cs_req_t bRequest;
+  uint8_t bChannelNumber;
+  uint8_t bControlSelector;
+  union
+  {
+    uint8_t bInterface;
+    uint8_t bEndpoint;
+  };
+  uint8_t bEntityID;
+  uint16_t wLength;
+} audio_control_request_t;
+
+// Helper for clock get requests
+static bool tud_audio_clock_get_request(uint8_t rhport, audio_control_request_t const *request)
+{
+  TU_ASSERT(request->bEntityID == UAC2_ENTITY_CLOCK);
+
+  // Example supports only single frequency, same value will be used for current value and range
+  if (request->bControlSelector == AUDIO_CS_CTRL_SAM_FREQ)
+  {
+    if (request->bRequest == AUDIO_CS_REQ_CUR)
+    {
+      TU_LOG2("Clock get current freq %u\r\n", AUDIO_SAMPLE_RATE);
+
+      audio_control_cur_4_t curf = { tu_htole32(AUDIO_SAMPLE_RATE) };
+      return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &curf, sizeof(curf));
+    }
+    else if (request->bRequest == AUDIO_CS_REQ_RANGE)
+    {
+      audio_control_range_4_n_t(1) rangef =
+      {
+        .wNumSubRanges = tu_htole16(1),
+        .subrange[0] = { tu_htole32(AUDIO_SAMPLE_RATE), tu_htole32(AUDIO_SAMPLE_RATE), 0}
+      };
+      TU_LOG2("Clock get freq range (%d, %d, %d)\r\n", (int)rangef.subrange[0].bMin, (int)rangef.subrange[0].bMax, (int)rangef.subrange[0].bRes);
+      return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &rangef, sizeof(rangef));
+    }
+  }
+  else if (request->bControlSelector == AUDIO_CS_CTRL_CLK_VALID &&
+           request->bRequest == AUDIO_CS_REQ_CUR)
+  {
+    audio_control_cur_1_t cur_valid = { .bCur = 1 };
+    TU_LOG2("Clock get is valid %u\r\n", cur_valid.bCur);
+    return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &cur_valid, sizeof(cur_valid));
+  }
+  TU_LOG1("Clock get request not supported, entity = %u, selector = %u, request = %u\r\n",
+          request->bEntityID, request->bControlSelector, request->bRequest);
+  return false;
+}
+
+// Helper for feature unit get requests
+static bool tud_audio_feature_unit_get_request(uint8_t rhport, audio_control_request_t const *request)
+{
+  TU_ASSERT(request->bEntityID == UAC2_ENTITY_SPK_FEATURE_UNIT);
+
+  if (request->bControlSelector == AUDIO_FU_CTRL_MUTE && request->bRequest == AUDIO_CS_REQ_CUR)
+  {
+    audio_control_cur_1_t mute1 = { .bCur = mute[request->bChannelNumber] };
+    TU_LOG2("Get channel %u mute %d\r\n", request->bChannelNumber, mute1.bCur);
+    return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &mute1, sizeof(mute1));
+  }
+  else if (UAC2_ENTITY_SPK_FEATURE_UNIT && request->bControlSelector == AUDIO_FU_CTRL_VOLUME)
+  {
+    if (request->bRequest == AUDIO_CS_REQ_RANGE)
+    {
+      audio_control_range_2_n_t(1) range_vol = {
+        .wNumSubRanges = tu_htole16(1),
+        .subrange[0] = { .bMin = tu_htole16(-VOLUME_CTRL_50_DB), tu_htole16(VOLUME_CTRL_0_DB), tu_htole16(256) }
+      };
+      TU_LOG2("Get channel %u volume range (%d, %d, %u) dB\r\n", request->bChannelNumber,
+              range_vol.subrange[0].bMin / 256, range_vol.subrange[0].bMax / 256, range_vol.subrange[0].bRes / 256);
+      return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &range_vol, sizeof(range_vol));
+    }
+    else if (request->bRequest == AUDIO_CS_REQ_CUR)
+    {
+      audio_control_cur_2_t cur_vol = { .bCur = tu_htole16(volume[request->bChannelNumber]) };
+      TU_LOG2("Get channel %u volume %u dB\r\n", request->bChannelNumber, cur_vol.bCur);
+      return tud_audio_buffer_and_schedule_control_xfer(rhport, (tusb_control_request_t const *)request, &cur_vol, sizeof(cur_vol));
+    }
+  }
+  TU_LOG1("Feature unit get request not supported, entity = %u, selector = %u, request = %u\r\n",
+          request->bEntityID, request->bControlSelector, request->bRequest);
+
+  return false;
+}
+
+// Helper for feature unit set requests
+static bool tud_audio_feature_unit_set_request(uint8_t rhport, audio_control_request_t const *request, uint8_t const *buf)
+{
+  (void)rhport;
+
+  TU_ASSERT(request->bEntityID == UAC2_ENTITY_SPK_FEATURE_UNIT);
+  TU_VERIFY(request->bRequest == AUDIO_CS_REQ_CUR);
+
+  if (request->bControlSelector == AUDIO_FU_CTRL_MUTE)
+  {
+    TU_VERIFY(request->wLength == sizeof(audio_control_cur_1_t));
+
+    mute[request->bChannelNumber] = ((audio_control_cur_1_t *)buf)->bCur;
+
+    TU_LOG2("Set channel %d Mute: %d\r\n", request->bChannelNumber, mute[request->bChannelNumber]);
+
+    return true;
+  }
+  else if (request->bControlSelector == AUDIO_FU_CTRL_VOLUME)
+  {
+    TU_VERIFY(request->wLength == sizeof(audio_control_cur_2_t));
+
+    volume[request->bChannelNumber] = ((audio_control_cur_2_t const *)buf)->bCur;
+
+    TU_LOG2("Set channel %d volume: %d dB\r\n", request->bChannelNumber, volume[request->bChannelNumber] / 256);
+
+    return true;
+  }
+  else
+  {
+    TU_LOG1("Feature unit set request not supported, entity = %u, selector = %u, request = %u\r\n",
+            request->bEntityID, request->bControlSelector, request->bRequest);
+    return false;
+  }
+}
+
+//--------------------------------------------------------------------+
+// Application Callback API Implementations
+//--------------------------------------------------------------------+
+
+// Invoked when audio class specific get request received for an entity
+bool tud_audio_get_req_entity_cb(uint8_t rhport, tusb_control_request_t const *p_request)
+{
+  audio_control_request_t *request = (audio_control_request_t *)p_request;
+
+  if (request->bEntityID == UAC2_ENTITY_CLOCK)
+    return tud_audio_clock_get_request(rhport, request);
+  if (request->bEntityID == UAC2_ENTITY_SPK_FEATURE_UNIT)
+    return tud_audio_feature_unit_get_request(rhport, request);
+  else
+  {
+    TU_LOG1("Get request not handled, entity = %d, selector = %d, request = %d\r\n",
+            request->bEntityID, request->bControlSelector, request->bRequest);
+  }
+  return false;
+}
+
+// Invoked when audio class specific set request received for an entity
+bool tud_audio_set_req_entity_cb(uint8_t rhport, tusb_control_request_t const *p_request, uint8_t *buf)
+{
+  audio_control_request_t const *request = (audio_control_request_t const *)p_request;
+
+  if (request->bEntityID == UAC2_ENTITY_SPK_FEATURE_UNIT)
+    return tud_audio_feature_unit_set_request(rhport, request, buf);
+
+  TU_LOG1("Set request not handled, entity = %d, selector = %d, request = %d\r\n",
+          request->bEntityID, request->bControlSelector, request->bRequest);
+
+  return false;
+}
+
+bool tud_audio_set_itf_close_EP_cb(uint8_t rhport, tusb_control_request_t const * p_request)
+{
+  (void)rhport;
+
+  uint8_t const itf = tu_u16_low(tu_le16toh(p_request->wIndex));
+  uint8_t const alt = tu_u16_low(tu_le16toh(p_request->wValue));
+
+  if (ITF_NUM_AUDIO_STREAMING_SPK == itf && alt == 0)
+      blink_interval_ms = BLINK_MOUNTED;
+
+  return true;
+}
+
+bool tud_audio_set_itf_cb(uint8_t rhport, tusb_control_request_t const * p_request)
+{
+  (void)rhport;
+  uint8_t const itf = tu_u16_low(tu_le16toh(p_request->wIndex));
+  uint8_t const alt = tu_u16_low(tu_le16toh(p_request->wValue));
+
+  TU_LOG2("Set interface %d alt %d\r\n", itf, alt);
+  if (ITF_NUM_AUDIO_STREAMING_SPK == itf && alt != 0)
+      blink_interval_ms = BLINK_STREAMING;
+
+  return true;
+}
+
+bool tud_audio_rx_done_cb(uint8_t rhport, uint8_t *buffer, uint16_t buf_size)
+{
+  (void)rhport;
+
+  spk_data_size = buf_size;
+  memcpy(spk_buf, buffer, buf_size);
+
+  return true;
+}
+
+bool tud_audio_tx_done_pre_load_cb(uint8_t rhport, uint8_t itf, uint8_t ep_in, uint8_t cur_alt_setting)
+{
+  (void)rhport;
+  (void)itf;
+  (void)ep_in;
+  (void)cur_alt_setting;
+
+  // This callback could be used to fill microphone data separately
+  return true;
+}
+
+//--------------------------------------------------------------------+
+// AUDIO Task
+//--------------------------------------------------------------------+
+
+void audio_task(void)
+{
+  // When new data arrived, copy data from speaker buffer, to microphone buffer
+  // and send it over
+  if (spk_data_size)
+  {
+    int16_t *src = spk_buf;
+    int16_t *limit = spk_buf + spk_data_size / 2;
+    int16_t *dst = mic_buf;
+    while (src < limit)
+    {
+      // Combine two channels into one
+      int32_t left = *src++;
+      int32_t right = *src++;
+      *dst++ = (int16_t)((left + right) / 2);
+    }
+    tud_audio_write((uint8_t *)mic_buf, spk_data_size / 2);
+    spk_data_size = 0;
+  }
+}
+
+//--------------------------------------------------------------------+
+// BLINKING TASK
+//--------------------------------------------------------------------+
+void led_blinking_task(void)
+{
+  static uint32_t start_ms = 0;
+  static bool led_state = false;
+
+  // Blink every interval ms
+  if (board_millis() - start_ms < blink_interval_ms) return;
+  start_ms += blink_interval_ms;
+
+  board_led_write(led_state);
+  led_state = 1 - led_state;
+}
diff --git a/examples/device/uac2_headset/src/tusb_config.h b/examples/device/uac2_headset/src/tusb_config.h
new file mode 100644
index 000000000..d19feeb86
--- /dev/null
+++ b/examples/device/uac2_headset/src/tusb_config.h
@@ -0,0 +1,134 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Ha Thach (tinyusb.org)
+ * Copyright (c) 2020 Jerzy Kasenberg
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#ifndef _TUSB_CONFIG_H_
+#define _TUSB_CONFIG_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+//--------------------------------------------------------------------
+// COMMON CONFIGURATION
+//--------------------------------------------------------------------
+
+// defined by compiler flags for flexibility
+#ifndef CFG_TUSB_MCU
+#error CFG_TUSB_MCU must be defined
+#endif
+
+#if CFG_TUSB_MCU == OPT_MCU_LPC43XX || CFG_TUSB_MCU == OPT_MCU_LPC18XX || CFG_TUSB_MCU == OPT_MCU_MIMXRT10XX
+#define CFG_TUSB_RHPORT0_MODE       (OPT_MODE_DEVICE | OPT_MODE_HIGH_SPEED)
+#else
+#define CFG_TUSB_RHPORT0_MODE       OPT_MODE_DEVICE
+#endif
+
+#define CFG_TUSB_OS                 OPT_OS_NONE
+
+#ifndef CFG_TUSB_DEBUG
+// Can be set during compilation i.e.: make LOG=<value for CFG_TUSB_DEBUG> BOARD=<bsp>
+// Keep in mind that enabling logs when data is streaming can disrupt data flow.
+// It can be very helpful though when audio unit requests are tested/debugged.
+#define CFG_TUSB_DEBUG              0
+#endif
+
+/* USB DMA on some MCUs can only access a specific SRAM region with restriction on alignment.
+ * Tinyusb use follows macros to declare transferring memory so that they can be put
+ * into those specific section.
+ * e.g
+ * - CFG_TUSB_MEM SECTION : __attribute__ (( section(".usb_ram") ))
+ * - CFG_TUSB_MEM_ALIGN   : __attribute__ ((aligned(4)))
+ */
+#ifndef CFG_TUSB_MEM_SECTION
+#define CFG_TUSB_MEM_SECTION
+#endif
+
+#ifndef CFG_TUSB_MEM_ALIGN
+#define CFG_TUSB_MEM_ALIGN          __attribute__ ((aligned(4)))
+#endif
+
+//--------------------------------------------------------------------
+// DEVICE CONFIGURATION
+//--------------------------------------------------------------------
+
+#ifndef CFG_TUD_ENDPOINT0_SIZE
+#define CFG_TUD_ENDPOINT0_SIZE    64
+#endif
+
+//------------- CLASS -------------//
+#define CFG_TUD_CDC               0
+#define CFG_TUD_MSC               0
+#define CFG_TUD_HID               0
+#define CFG_TUD_MIDI              0
+#define CFG_TUD_AUDIO             1
+#define CFG_TUD_VENDOR            0
+
+//--------------------------------------------------------------------
+// AUDIO CLASS DRIVER CONFIGURATION
+//--------------------------------------------------------------------
+
+#ifndef AUDIO_SAMPLE_RATE
+#define AUDIO_SAMPLE_RATE                   48000
+#endif
+
+#define CFG_TUD_AUDIO_IN_PATH               (CFG_TUD_AUDIO)
+#define CFG_TUD_AUDIO_OUT_PATH              (CFG_TUD_AUDIO)
+
+// Audio format type
+#define CFG_TUD_AUDIO_FORMAT_TYPE_TX        AUDIO_FORMAT_TYPE_I
+#define CFG_TUD_AUDIO_FORMAT_TYPE_RX        AUDIO_FORMAT_TYPE_I
+
+// Audio format type I specifications
+#define CFG_TUD_AUDIO_FORMAT_TYPE_I_TX      AUDIO_DATA_FORMAT_TYPE_I_PCM
+#define CFG_TUD_AUDIO_FORMAT_TYPE_I_RX      AUDIO_DATA_FORMAT_TYPE_I_PCM
+#define CFG_TUD_AUDIO_N_CHANNELS_TX         1
+#define CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX 2
+#define CFG_TUD_AUDIO_N_CHANNELS_RX         2
+#define CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_RX 2
+#define CFG_TUD_AUDIO_RX_ITEMSIZE           2
+#define CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP    0
+
+// EP and buffer size - for isochronous EP´s, the buffer and EP size are equal (different sizes would not make sense)
+#define CFG_TUD_AUDIO_EPSIZE_IN           (CFG_TUD_AUDIO_IN_PATH * (48 + 1) * (CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_TX) * (CFG_TUD_AUDIO_N_CHANNELS_TX)) // 48 Samples (48 kHz) x 2 Bytes/Sample x n Channels
+#define CFG_TUD_AUDIO_TX_FIFO_COUNT       (CFG_TUD_AUDIO_IN_PATH * 1)
+#define CFG_TUD_AUDIO_TX_FIFO_SIZE        (CFG_TUD_AUDIO_IN_PATH ? ((CFG_TUD_AUDIO_EPSIZE_IN)) : 0)
+
+// EP and buffer size - for isochronous EP´s, the buffer and EP size are equal (different sizes would not make sense)
+#define CFG_TUD_AUDIO_EPSIZE_OUT          (CFG_TUD_AUDIO_OUT_PATH * ((48 + CFG_TUD_AUDIO_ENABLE_FEEDBACK_EP) * (CFG_TUD_AUDIO_N_BYTES_PER_SAMPLE_RX) * (CFG_TUD_AUDIO_N_CHANNELS_RX))) // N Samples (N kHz) x 2 Bytes/Sample x n Channels
+#define CFG_TUD_AUDIO_RX_FIFO_COUNT       (CFG_TUD_AUDIO_OUT_PATH * 1)
+#define CFG_TUD_AUDIO_RX_FIFO_SIZE        (CFG_TUD_AUDIO_OUT_PATH ? (3 * (CFG_TUD_AUDIO_EPSIZE_OUT / CFG_TUD_AUDIO_RX_FIFO_COUNT)) : 0)
+
+// Number of Standard AS Interface Descriptors (4.9.1) defined per audio function - this is required to be able to remember the current alternate settings of these interfaces - We restrict us here to have a constant number for all audio functions (which means this has to be the maximum number of AS interfaces an audio function has and a second audio function with less AS interfaces just wastes a few bytes)
+#define CFG_TUD_AUDIO_N_AS_INT 			   		1
+
+// Size of control request buffer
+#define CFG_TUD_AUDIO_CTRL_BUF_SIZE 				64
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _TUSB_CONFIG_H_ */
diff --git a/examples/device/uac2_headset/src/usb_descriptors.c b/examples/device/uac2_headset/src/usb_descriptors.c
new file mode 100644
index 000000000..940f0fe2b
--- /dev/null
+++ b/examples/device/uac2_headset/src/usb_descriptors.c
@@ -0,0 +1,165 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Ha Thach (tinyusb.org)
+ * Copyright (c) 2020 Jerzy Kasenberg
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#include "tusb.h"
+#include "usb_descriptors.h"
+
+/* A combination of interfaces must have a unique product id, since PC will save device driver after the first plug.
+ * Same VID/PID with different interface e.g MSC (first), then CDC (later) will possibly cause system error on PC.
+ *
+ * Auto ProductID layout's Bitmap:
+ *   [MSB]     AUDIO | MIDI | HID | MSC | CDC          [LSB]
+ */
+#define _PID_MAP(itf, n)  ( (CFG_TUD_##itf) << (n) )
+#define USB_PID           (0x4000 | _PID_MAP(CDC, 0) | _PID_MAP(MSC, 1) | _PID_MAP(HID, 2) | \
+    _PID_MAP(MIDI, 3) | _PID_MAP(AUDIO, 4) | _PID_MAP(VENDOR, 5) )
+
+//--------------------------------------------------------------------+
+// Device Descriptors
+//--------------------------------------------------------------------+
+tusb_desc_device_t const desc_device =
+{
+    .bLength            = sizeof(tusb_desc_device_t),
+    .bDescriptorType    = TUSB_DESC_DEVICE,
+    .bcdUSB             = 0x0200,
+
+    // Use Interface Association Descriptor (IAD) for CDC
+    // As required by USB Specs IAD's subclass must be common class (2) and protocol must be IAD (1)
+    .bDeviceClass       = TUSB_CLASS_MISC,
+    .bDeviceSubClass    = MISC_SUBCLASS_COMMON,
+    .bDeviceProtocol    = MISC_PROTOCOL_IAD,
+    .bMaxPacketSize0    = CFG_TUD_ENDPOINT0_SIZE,
+
+    .idVendor           = 0xCafe,
+    .idProduct          = USB_PID,
+    .bcdDevice          = 0x0100,
+
+    .iManufacturer      = 0x01,
+    .iProduct           = 0x02,
+    .iSerialNumber      = 0x03,
+
+    .bNumConfigurations = 0x01
+};
+
+// Invoked when received GET DEVICE DESCRIPTOR
+// Application return pointer to descriptor
+uint8_t const * tud_descriptor_device_cb(void)
+{
+  return (uint8_t const *)&desc_device;
+}
+
+//--------------------------------------------------------------------+
+// Configuration Descriptor
+//--------------------------------------------------------------------+
+#define CONFIG_TOTAL_LEN    	(TUD_CONFIG_DESC_LEN + CFG_TUD_AUDIO * TUD_AUDIO_HEADSET_STEREO_DESC_LEN)
+
+#if CFG_TUSB_MCU == OPT_MCU_LPC175X_6X || CFG_TUSB_MCU == OPT_MCU_LPC177X_8X || CFG_TUSB_MCU == OPT_MCU_LPC40XX
+// LPC 17xx and 40xx endpoint type (bulk/interrupt/iso) are fixed by its number
+// 0 control, 1 In, 2 Bulk, 3 Iso, 4 In etc ...
+#define EPNUM_AUDIO   0x03
+#elif CFG_TUSB_MCU == OPT_MCU_NRF5X
+// ISO endpoints for NRF5x are fixed to 0x08 (0x88)
+#define EPNUM_AUDIO   0x08
+#else
+#define EPNUM_AUDIO   0x01
+#endif
+
+// These variables are required by the audio driver in audio_device.c
+
+// List of audio descriptor lengths which is required by audio driver - you need as many entries as CFG_TUD_AUDIO
+const uint16_t tud_audio_desc_lengths[] = {TUD_AUDIO_HEADSET_STEREO_DESC_LEN};
+
+uint8_t const desc_configuration[] =
+{
+    // Interface count, string index, total length, attribute, power in mA
+    TUD_CONFIG_DESCRIPTOR(1, ITF_NUM_TOTAL, 0, CONFIG_TOTAL_LEN, TUSB_DESC_CONFIG_ATT_REMOTE_WAKEUP, 100),
+
+    // Interface number, string index, EP Out & EP In address, EP size
+    TUD_AUDIO_HEADSET_STEREO_DESCRIPTOR(2, 2, 16, EPNUM_AUDIO, CFG_TUD_AUDIO_EPSIZE_OUT, EPNUM_AUDIO | 0x80, CFG_TUD_AUDIO_EPSIZE_IN)
+};
+
+// Invoked when received GET CONFIGURATION DESCRIPTOR
+// Application return pointer to descriptor
+// Descriptor contents must exist long enough for transfer to complete
+uint8_t const * tud_descriptor_configuration_cb(uint8_t index)
+{
+  (void)index; // for multiple configurations
+  return desc_configuration;
+}
+
+//--------------------------------------------------------------------+
+// String Descriptors
+//--------------------------------------------------------------------+
+
+// array of pointer to string descriptors
+char const* string_desc_arr [] =
+{
+  (const char[]) { 0x09, 0x04 },  // 0: is supported language is English (0x0409)
+  "TinyUSB",                      // 1: Manufacturer
+  "TinyUSB headset",              // 2: Product
+  "000001",                       // 3: Serials, should use chip ID
+  "TinyUSB Speakers",             // 4: Audio Interface
+  "TinyUSB Microphone",           // 5: Audio Interface
+};
+
+static uint16_t _desc_str[32];
+
+// Invoked when received GET STRING DESCRIPTOR request
+// Application return pointer to descriptor, whose contents must exist long enough for transfer to complete
+uint16_t const* tud_descriptor_string_cb(uint8_t index, uint16_t langid)
+{
+  (void)langid;
+
+  uint8_t chr_count;
+
+  if (index == 0)
+  {
+    memcpy(&_desc_str[1], string_desc_arr[0], 2);
+    chr_count = 1;
+  }
+  else
+  {
+    // Convert ASCII string into UTF-16
+
+    if (!(index < sizeof(string_desc_arr)/sizeof(string_desc_arr[0]))) return NULL;
+
+    const char* str = string_desc_arr[index];
+
+    // Cap at max char
+    chr_count = strlen(str);
+    if (chr_count > 31) chr_count = 31;
+
+    for (uint8_t i = 0; i < chr_count; i++)
+    {
+      _desc_str[1 + i] = str[i];
+    }
+  }
+
+  // first byte is length (including header), second byte is string type
+  _desc_str[0] = (TUSB_DESC_STRING << 8 ) | (2 * chr_count + 2);
+
+  return _desc_str;
+}
diff --git a/examples/device/uac2_headset/src/usb_descriptors.h b/examples/device/uac2_headset/src/usb_descriptors.h
new file mode 100644
index 000000000..6651897b0
--- /dev/null
+++ b/examples/device/uac2_headset/src/usb_descriptors.h
@@ -0,0 +1,120 @@
+/* 
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2020 Jerzy Kasenbreg
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ */
+
+#ifndef _USB_DESCRIPTORS_H_
+#define _USB_DESCRIPTORS_H_
+
+#include "tusb.h"
+
+// Unit numbers are arbitrary selected
+#define UAC2_ENTITY_CLOCK               0x04
+// Speaker path
+#define UAC2_ENTITY_SPK_INPUT_TERMINAL  0x01
+#define UAC2_ENTITY_SPK_FEATURE_UNIT    0x02
+#define UAC2_ENTITY_SPK_OUTPUT_TERMINAL 0x03
+// Microphone path
+#define UAC2_ENTITY_MIC_INPUT_TERMINAL  0x11
+#define UAC2_ENTITY_MIC_OUTPUT_TERMINAL 0x13
+
+enum
+{
+  ITF_NUM_AUDIO_CONTROL = 0,
+  ITF_NUM_AUDIO_STREAMING_SPK,
+  ITF_NUM_AUDIO_STREAMING_MIC,
+  ITF_NUM_TOTAL
+};
+
+#define TUD_AUDIO_HEADSET_STEREO_DESC_LEN (TUD_AUDIO_DESC_IAD_LEN\
+    + TUD_AUDIO_DESC_STD_AC_LEN\
+    + TUD_AUDIO_DESC_CS_AC_LEN\
+    + TUD_AUDIO_DESC_CLK_SRC_LEN\
+    + TUD_AUDIO_DESC_INPUT_TERM_LEN\
+    + TUD_AUDIO_DESC_FEATURE_UNIT_TWO_CHANNEL_LEN\
+    + TUD_AUDIO_DESC_OUTPUT_TERM_LEN\
+    + TUD_AUDIO_DESC_INPUT_TERM_LEN\
+    + TUD_AUDIO_DESC_OUTPUT_TERM_LEN\
+    + TUD_AUDIO_DESC_STD_AS_INT_LEN\
+    + TUD_AUDIO_DESC_STD_AS_INT_LEN\
+    + TUD_AUDIO_DESC_CS_AS_INT_LEN\
+    + TUD_AUDIO_DESC_TYPE_I_FORMAT_LEN\
+    + TUD_AUDIO_DESC_STD_AS_ISO_EP_LEN\
+    + TUD_AUDIO_DESC_CS_AS_ISO_EP_LEN\
+    + TUD_AUDIO_DESC_STD_AS_INT_LEN\
+    + TUD_AUDIO_DESC_STD_AS_INT_LEN\
+    + TUD_AUDIO_DESC_CS_AS_INT_LEN\
+    + TUD_AUDIO_DESC_TYPE_I_FORMAT_LEN\
+    + TUD_AUDIO_DESC_STD_AS_ISO_EP_LEN\
+    + TUD_AUDIO_DESC_CS_AS_ISO_EP_LEN)
+
+
+#define TUD_AUDIO_HEADSET_STEREO_DESCRIPTOR(_stridx, _nBytesPerSample, _nBitsUsedPerSample, _epout, _epoutsize, _epin, _epinsize) \
+    /* Standard Interface Association Descriptor (IAD) */\
+    TUD_AUDIO_DESC_IAD(/*_firstitfs*/ ITF_NUM_AUDIO_CONTROL, /*_nitfs*/ ITF_NUM_TOTAL, /*_stridx*/ 0x00),\
+    /* Standard AC Interface Descriptor(4.7.1) */\
+    TUD_AUDIO_DESC_STD_AC(/*_itfnum*/ ITF_NUM_AUDIO_CONTROL, /*_nEPs*/ 0x00, /*_stridx*/ _stridx),\
+    /* Class-Specific AC Interface Header Descriptor(4.7.2) */\
+    TUD_AUDIO_DESC_CS_AC(/*_bcdADC*/ 0x0200, /*_category*/ AUDIO_FUNC_HEADSET, /*_totallen*/ TUD_AUDIO_DESC_CLK_SRC_LEN+TUD_AUDIO_DESC_FEATURE_UNIT_TWO_CHANNEL_LEN+TUD_AUDIO_DESC_INPUT_TERM_LEN+TUD_AUDIO_DESC_OUTPUT_TERM_LEN+TUD_AUDIO_DESC_INPUT_TERM_LEN+TUD_AUDIO_DESC_OUTPUT_TERM_LEN, /*_ctrl*/ AUDIO_CS_AS_INTERFACE_CTRL_LATENCY_POS),\
+    /* Clock Source Descriptor(4.7.2.1) */\
+    TUD_AUDIO_DESC_CLK_SRC(/*_clkid*/ UAC2_ENTITY_CLOCK, /*_attr*/ 3, /*_ctrl*/ 5, /*_assocTerm*/ 0x00,  /*_stridx*/ 0x00),    \
+    /* Input Terminal Descriptor(4.7.2.4) */\
+    TUD_AUDIO_DESC_INPUT_TERM(/*_termid*/ UAC2_ENTITY_SPK_INPUT_TERMINAL, /*_termtype*/ AUDIO_TERM_TYPE_USB_STREAMING, /*_assocTerm*/ 0x00, /*_clkid*/ UAC2_ENTITY_CLOCK, /*_nchannelslogical*/ 0x02, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_idxchannelnames*/ 0x00, /*_ctrl*/ 0 * (AUDIO_CTRL_R << AUDIO_IN_TERM_CTRL_CONNECTOR_POS), /*_stridx*/ 0x00),\
+    /* Feature Unit Descriptor(4.7.2.8) */\
+    TUD_AUDIO_DESC_FEATURE_UNIT_TWO_CHANNEL(/*_unitid*/ UAC2_ENTITY_SPK_FEATURE_UNIT, /*_srcid*/ UAC2_ENTITY_SPK_INPUT_TERMINAL, /*_ctrlch0master*/ (AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_MUTE_POS | AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_VOLUME_POS), /*_ctrlch1*/ (AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_MUTE_POS | AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_VOLUME_POS), /*_ctrlch2*/ (AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_MUTE_POS | AUDIO_CTRL_RW << AUDIO_FEATURE_UNIT_CTRL_VOLUME_POS), /*_stridx*/ 0x00),\
+    /* Output Terminal Descriptor(4.7.2.5) */\
+    TUD_AUDIO_DESC_OUTPUT_TERM(/*_termid*/ UAC2_ENTITY_SPK_OUTPUT_TERMINAL, /*_termtype*/ AUDIO_TERM_TYPE_OUT_GENERIC_SPEAKER, /*_assocTerm*/ 0x00, /*_srcid*/ UAC2_ENTITY_SPK_FEATURE_UNIT, /*_clkid*/ UAC2_ENTITY_CLOCK, /*_ctrl*/ 0x0000, /*_stridx*/ 0x00),\
+    /* Input Terminal Descriptor(4.7.2.4) */\
+    TUD_AUDIO_DESC_INPUT_TERM(/*_termid*/ UAC2_ENTITY_MIC_INPUT_TERMINAL, /*_termtype*/ AUDIO_TERM_TYPE_IN_GENERIC_MIC, /*_assocTerm*/ 0x00, /*_clkid*/ UAC2_ENTITY_CLOCK, /*_nchannelslogical*/ 0x01, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_idxchannelnames*/ 0x00, /*_ctrl*/ 0 * (AUDIO_CTRL_R << AUDIO_IN_TERM_CTRL_CONNECTOR_POS), /*_stridx*/ 0x00),\
+    /* Output Terminal Descriptor(4.7.2.5) */\
+    TUD_AUDIO_DESC_OUTPUT_TERM(/*_termid*/ UAC2_ENTITY_MIC_OUTPUT_TERMINAL, /*_termtype*/ AUDIO_TERM_TYPE_USB_STREAMING, /*_assocTerm*/ 0x00, /*_srcid*/ UAC2_ENTITY_MIC_INPUT_TERMINAL, /*_clkid*/ UAC2_ENTITY_CLOCK, /*_ctrl*/ 0x0000, /*_stridx*/ 0x00),\
+    /* Standard AS Interface Descriptor(4.9.1) */\
+    /* Interface 1, Alternate 0 - default alternate setting with 0 bandwidth */\
+    TUD_AUDIO_DESC_STD_AS_INT(/*_itfnum*/ (uint8_t)(ITF_NUM_AUDIO_STREAMING_SPK), /*_altset*/ 0x00, /*_nEPs*/ 0x00, /*_stridx*/ 0x05),\
+    /* Standard AS Interface Descriptor(4.9.1) */\
+    /* Interface 1, Alternate 1 - alternate interface for data streaming */\
+    TUD_AUDIO_DESC_STD_AS_INT(/*_itfnum*/ (uint8_t)(ITF_NUM_AUDIO_STREAMING_SPK), /*_altset*/ 0x01, /*_nEPs*/ 0x01, /*_stridx*/ 0x05),\
+    /* Class-Specific AS Interface Descriptor(4.9.2) */\
+    TUD_AUDIO_DESC_CS_AS_INT(/*_termid*/ UAC2_ENTITY_SPK_INPUT_TERMINAL, /*_ctrl*/ AUDIO_CTRL_NONE, /*_formattype*/ AUDIO_FORMAT_TYPE_I, /*_formats*/ AUDIO_DATA_FORMAT_TYPE_I_PCM, /*_nchannelsphysical*/ 0x02, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_stridx*/ 0x00),\
+    /* Type I Format Type Descriptor(2.3.1.6 - Audio Formats) */\
+    TUD_AUDIO_DESC_TYPE_I_FORMAT(_nBytesPerSample, _nBitsUsedPerSample),\
+    /* Standard AS Isochronous Audio Data Endpoint Descriptor(4.10.1.1) */\
+    TUD_AUDIO_DESC_STD_AS_ISO_EP(/*_ep*/ _epout, /*_attr*/ (TUSB_XFER_ISOCHRONOUS | TUSB_ISO_EP_ATT_ADAPTIVE | TUSB_ISO_EP_ATT_DATA), /*_maxEPsize*/ _epoutsize, /*_interval*/ (CFG_TUSB_RHPORT0_MODE & OPT_MODE_HIGH_SPEED) ? 0x04 : 0x01),\
+    /* Class-Specific AS Isochronous Audio Data Endpoint Descriptor(4.10.1.2) */\
+    TUD_AUDIO_DESC_CS_AS_ISO_EP(/*_attr*/ AUDIO_CS_AS_ISO_DATA_EP_ATT_NON_MAX_PACKETS_OK, /*_ctrl*/ AUDIO_CTRL_NONE, /*_lockdelayunit*/ AUDIO_CS_AS_ISO_DATA_EP_LOCK_DELAY_UNIT_MILLISEC, /*_lockdelay*/ 0x0001),\
+    /* Standard AS Interface Descriptor(4.9.1) */\
+    /* Interface 2, Alternate 0 - default alternate setting with 0 bandwidth */\
+    TUD_AUDIO_DESC_STD_AS_INT(/*_itfnum*/ (uint8_t)(ITF_NUM_AUDIO_STREAMING_MIC), /*_altset*/ 0x00, /*_nEPs*/ 0x00, /*_stridx*/ 0x04),\
+    /* Standard AS Interface Descriptor(4.9.1) */\
+    /* Interface 1, Alternate 1 - alternate interface for data streaming */\
+    TUD_AUDIO_DESC_STD_AS_INT(/*_itfnum*/ (uint8_t)(ITF_NUM_AUDIO_STREAMING_MIC), /*_altset*/ 0x01, /*_nEPs*/ 0x01, /*_stridx*/ 0x04),\
+    /* Class-Specific AS Interface Descriptor(4.9.2) */\
+    TUD_AUDIO_DESC_CS_AS_INT(/*_termid*/ UAC2_ENTITY_MIC_OUTPUT_TERMINAL, /*_ctrl*/ AUDIO_CTRL_NONE, /*_formattype*/ AUDIO_FORMAT_TYPE_I, /*_formats*/ AUDIO_DATA_FORMAT_TYPE_I_PCM, /*_nchannelsphysical*/ 0x01, /*_channelcfg*/ AUDIO_CHANNEL_CONFIG_NON_PREDEFINED, /*_stridx*/ 0x00),\
+    /* Type I Format Type Descriptor(2.3.1.6 - Audio Formats) */\
+    TUD_AUDIO_DESC_TYPE_I_FORMAT(_nBytesPerSample, _nBitsUsedPerSample),\
+    /* Standard AS Isochronous Audio Data Endpoint Descriptor(4.10.1.1) */\
+    TUD_AUDIO_DESC_STD_AS_ISO_EP(/*_ep*/ _epin, /*_attr*/ (TUSB_XFER_ISOCHRONOUS | TUSB_ISO_EP_ATT_ASYNCHRONOUS | TUSB_ISO_EP_ATT_DATA), /*_maxEPsize*/ _epinsize, /*_interval*/ (CFG_TUSB_RHPORT0_MODE & OPT_MODE_HIGH_SPEED) ? 0x04 : 0x01),\
+    /* Class-Specific AS Isochronous Audio Data Endpoint Descriptor(4.10.1.2) */\
+    TUD_AUDIO_DESC_CS_AS_ISO_EP(/*_attr*/ AUDIO_CS_AS_ISO_DATA_EP_ATT_NON_MAX_PACKETS_OK, /*_ctrl*/ AUDIO_CTRL_NONE, /*_lockdelayunit*/ AUDIO_CS_AS_ISO_DATA_EP_LOCK_DELAY_UNIT_UNDEFINED, /*_lockdelay*/ 0x0000)\
+
+#endif
diff --git a/examples/host/cdc_msc_hid/.only.MCU_LPC175X_6X b/examples/host/cdc_msc_hid/.only.MCU_LPC175X_6X
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/examples/host/cdc_msc_hid/.only.MCU_LPC175X_6X
diff --git a/examples/host/cdc_msc_hid/.only.MCU_LPC177X_8X b/examples/host/cdc_msc_hid/.only.MCU_LPC177X_8X
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/examples/host/cdc_msc_hid/.only.MCU_LPC177X_8X
diff --git a/examples/host/cdc_msc_hid/.only.MCU_LPC18XX b/examples/host/cdc_msc_hid/.only.MCU_LPC18XX
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/examples/host/cdc_msc_hid/.only.MCU_LPC18XX
diff --git a/examples/host/cdc_msc_hid/.only.MCU_LPC40XX b/examples/host/cdc_msc_hid/.only.MCU_LPC40XX
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/examples/host/cdc_msc_hid/.only.MCU_LPC40XX
diff --git a/examples/host/cdc_msc_hid/.only.MCU_LPC43XX b/examples/host/cdc_msc_hid/.only.MCU_LPC43XX
new file mode 100644
index 000000000..e69de29bb
--- /dev/null
+++ b/examples/host/cdc_msc_hid/.only.MCU_LPC43XX
diff --git a/examples/host/cdc_msc_hid/Makefile b/examples/host/cdc_msc_hid/Makefile
new file mode 100644
index 000000000..35de0a9a0
--- /dev/null
+++ b/examples/host/cdc_msc_hid/Makefile
@@ -0,0 +1,26 @@
+include ../../../tools/top.mk
+include ../../make.mk
+
+INC += \
+	src \
+	$(TOP)/hw \
+
+# Example source
+EXAMPLE_SOURCE += $(wildcard src/*.c)
+SRC_C += $(addprefix $(CURRENT_PATH)/, $(EXAMPLE_SOURCE))
+
+CFLAGS += -Wno-error=cast-align
+
+# TinyUSB Host Stack source
+SRC_C += \
+	src/class/cdc/cdc_host.c \
+	src/class/hid/hid_host.c \
+	src/class/msc/msc_host.c \
+	src/host/usbh.c \
+	src/host/hub.c \
+	src/host/ehci/ehci.c \
+	src/host/ohci/ohci.c \
+	src/portable/nxp/lpc18_43/hcd_lpc18_43.c \
+	src/portable/nxp/lpc17_40/hcd_lpc17_40.c
+
+include ../../rules.mk
diff --git a/examples/host/cdc_msc_hid/ses/lpc175x_6x/lpc175x_6x.emProject b/examples/host/cdc_msc_hid/ses/lpc175x_6x/lpc175x_6x.emProject
index ba5a9cea7..8a2c36390 100644
--- a/examples/host/cdc_msc_hid/ses/lpc175x_6x/lpc175x_6x.emProject
+++ b/examples/host/cdc_msc_hid/ses/lpc175x_6x/lpc175x_6x.emProject
@@ -19,8 +19,8 @@
       arm_target_device_name="LPC1769"
       arm_target_interface_type="SWD"
       build_treat_warnings_as_errors="Yes"
-      c_preprocessor_definitions="LPC175x_6x;__LPC1700_FAMILY;__LPC176x_SUBFAMILY;ARM_MATH_CM3;FLASH_PLACEMENT=1;CORE_M3;BOARD_LPCXPRESSO1769;CFG_TUSB_MCU=OPT_MCU_LPC175X_6X"
-      c_user_include_directories="../../src;$(rootDir)/hw;$(rootDir)/src;$(lpcDir)/inc"
+      c_preprocessor_definitions="LPC175x_6x;__LPC1700_FAMILY;__LPC176x_SUBFAMILY;ARM_MATH_CM3;FLASH_PLACEMENT=1;CORE_M3;BOARD_LPCXPRESSO1769;CFG_TUSB_MCU=OPT_MCU_LPC175X_6X;CFG_TUSB_DEBUG=2;LOGGER_RTT"
+      c_user_include_directories="../../src;$(rootDir)/hw;$(rootDir)/src;$(lpcDir)/inc;$(rootDir)/lib/SEGGER_RTT/RTT"
       debug_register_definition_file="LPC176x5x_Registers.xml"
       debug_target_connection="J-Link"
       gcc_enable_all_warnings="Yes"
@@ -101,12 +101,19 @@
       <file file_name="LPC176x5x_Vectors.s" />
       <file file_name="thumb_crt0.s" />
     </folder>
-    <folder
-      Name="segger_rtt"
-      exclude=""
-      filter="*.c;*.h"
-      path="../../../../../lib/segger_rtt"
-      recurse="No" />
+    <folder Name="lib">
+      <folder Name="SEGGER_RTT">
+        <folder Name="RTT">
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT.c" />
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT.h" />
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT_Conf.h" />
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT_printf.c" />
+        </folder>
+        <folder Name="Syscalls">
+          <file file_name="../../../../../lib/SEGGER_RTT/Syscalls/SEGGER_RTT_Syscalls_SES.c" />
+        </folder>
+      </folder>
+    </folder>
   </project>
   <configuration Name="LPCXpresso 1769" />
 </solution>
diff --git a/examples/host/cdc_msc_hid/ses/lpc18xx/lpc18xx.emProject b/examples/host/cdc_msc_hid/ses/lpc18xx/lpc18xx.emProject
index 2dd7de552..2b5538957 100644
--- a/examples/host/cdc_msc_hid/ses/lpc18xx/lpc18xx.emProject
+++ b/examples/host/cdc_msc_hid/ses/lpc18xx/lpc18xx.emProject
@@ -17,8 +17,8 @@
       arm_target_debug_interface_type="ADIv5"
       arm_target_device_name="LPC1857"
       arm_target_interface_type="SWD"
-      c_preprocessor_definitions="LPC18xx;__LPC1800_FAMILY;__LPC185x_SUBFAMILY;ARM_MATH_CM3;FLASH_PLACEMENT=1;CORE_M3;BOARD_MCB1800;CFG_TUSB_MCU=OPT_MCU_LPC18XX;CFG_TUSB_MEM_SECTION= __attribute__((section(&quot;.bss2&quot;)))"
-      c_user_include_directories="../../src;$(rootDir)/hw;$(rootDir)/src;$(lpcDir)//inc;$(lpcDir)//inc/config_18xx"
+      c_preprocessor_definitions="LPC18xx;__LPC1800_FAMILY;__LPC185x_SUBFAMILY;ARM_MATH_CM3;FLASH_PLACEMENT=1;CORE_M3;BOARD_MCB1800;CFG_TUSB_MCU=OPT_MCU_LPC18XX;CFG_TUSB_MEM_SECTION= __attribute__((section(&quot;.bss2&quot;)));CFG_TUSB_DEBUG=2"
+      c_user_include_directories="../../src;$(rootDir)/hw;$(rootDir)/src;$(lpcDir)//inc;$(lpcDir)//inc/config_18xx;$(rootDir)/lib/SEGGER_RTT/RTT"
       debug_register_definition_file="$(ProjectDir)/LPC18xx_Registers.xml"
       debug_target_connection="J-Link"
       gcc_entry_point="Reset_Handler"
@@ -53,6 +53,7 @@
         <folder Name="mcb1800">
           <file file_name="../../../../../hw/bsp/mcb1800/mcb1800.c" />
         </folder>
+        <file file_name="../../../../../hw/bsp/board.c" />
       </folder>
       <folder Name="mcu">
         <folder Name="nxp">
@@ -102,12 +103,6 @@
       </folder>
     </folder>
     <folder
-      Name="segger_rtt"
-      exclude=""
-      filter="*.c;*.h"
-      path="../../../../../lib/segger_rtt"
-      recurse="No" />
-    <folder
       Name="src"
       exclude=""
       filter="*.c;*.h"
@@ -119,6 +114,21 @@
       filter="*.c;*.h"
       path="../../../../../src"
       recurse="Yes" />
+    <folder Name="lib">
+      <folder Name="SEGGER_RTT">
+        <folder Name="RTT">
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT.c" />
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT_printf.c" />
+        </folder>
+        <folder Name="Syscalls">
+          <file file_name="../../../../../lib/SEGGER_RTT/Syscalls/SEGGER_RTT_Syscalls_SES.c" />
+        </folder>
+      </folder>
+    </folder>
+    <configuration
+      Name="MCB1800"
+      arm_target_interface_type="JTAG"
+      speed="12000" />
   </project>
   <configuration
     Name="MCB1800"
diff --git a/examples/host/cdc_msc_hid/ses/lpc40xx/lpc40xx.emProject b/examples/host/cdc_msc_hid/ses/lpc40xx/lpc40xx.emProject
index bfb7922a3..68995f1a5 100644
--- a/examples/host/cdc_msc_hid/ses/lpc40xx/lpc40xx.emProject
+++ b/examples/host/cdc_msc_hid/ses/lpc40xx/lpc40xx.emProject
@@ -18,8 +18,8 @@
       arm_target_debug_interface_type="ADIv5"
       arm_target_device_name="LPC4088"
       arm_target_interface_type="SWD"
-      c_preprocessor_definitions="CORE_M4;__LPC4000_FAMILY;__LPC408x_SUBFAMILY;ARM_MATH_CM4;FLASH_PLACEMENT=1;BOARD_EA4088QS;CFG_TUSB_MCU=OPT_MCU_LPC40XX;CFG_TUSB_MEM_SECTION= __attribute__((section(&quot;.bss2&quot;)))"
-      c_user_include_directories="../../src;$(rootDir)/hw;$(rootDir)/src;$(lpcDir)/inc"
+      c_preprocessor_definitions="CORE_M4;__LPC4000_FAMILY;__LPC408x_SUBFAMILY;ARM_MATH_CM4;FLASH_PLACEMENT=1;BOARD_EA4088QS;CFG_TUSB_MCU=OPT_MCU_LPC40XX;CFG_TUSB_MEM_SECTION= __attribute__((section(&quot;.bss2&quot;)));CFG_TUSB_DEBUG=2;LOGGER_RTT"
+      c_user_include_directories="../../src;$(rootDir)/hw;$(rootDir)/src;$(lpcDir)/inc;$(rootDir)/lib/SEGGER_RTT/RTT"
       debug_register_definition_file="$(ProjectDir)/LPC408x_7x_Registers.xml"
       debug_target_connection="J-Link"
       gcc_enable_all_warnings="Yes"
@@ -55,6 +55,7 @@
         <folder Name="ea4088qs">
           <file file_name="../../../../../hw/bsp/ea4088qs/ea4088qs.c" />
         </folder>
+        <file file_name="../../../../../hw/bsp/board.c" />
       </folder>
       <folder Name="mcu">
         <folder Name="nxp">
@@ -92,12 +93,6 @@
       </folder>
     </folder>
     <folder
-      Name="segger_rtt"
-      exclude=""
-      filter="*.c;*.h"
-      path="../../../../../lib/segger_rtt"
-      recurse="No" />
-    <folder
       Name="src"
       exclude=""
       filter="*.c;*.h"
@@ -109,6 +104,19 @@
       filter="*.c;*.h"
       path="../../../../../src"
       recurse="Yes" />
+    <folder Name="lib">
+      <folder Name="SEGGER_RTT">
+        <folder Name="RTT">
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT.c" />
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT.h" />
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT_Conf.h" />
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT_printf.c" />
+        </folder>
+        <folder Name="Syscalls">
+          <file file_name="../../../../../lib/SEGGER_RTT/Syscalls/SEGGER_RTT_Syscalls_SES.c" />
+        </folder>
+      </folder>
+    </folder>
   </project>
   <configuration
     Name="EA4088 QuickStart"
diff --git a/examples/host/cdc_msc_hid/ses/lpc43xx/lpc43xx.emProject b/examples/host/cdc_msc_hid/ses/lpc43xx/lpc43xx.emProject
index 3b93c623c..2d99ae6c8 100644
--- a/examples/host/cdc_msc_hid/ses/lpc43xx/lpc43xx.emProject
+++ b/examples/host/cdc_msc_hid/ses/lpc43xx/lpc43xx.emProject
@@ -20,7 +20,7 @@
       arm_target_interface_type="SWD"
       build_treat_warnings_as_errors="No"
       c_preprocessor_definitions="CORE_M4;__LPC4300_FAMILY;__LPC435x_SUBFAMILY;ARM_MATH_CM4;FLASH_PLACEMENT=1;BOARD_EA4357;CFG_TUSB_MCU=OPT_MCU_LPC43XX;CFG_TUSB_MEM_SECTION= __attribute__((section(&quot;.bss2&quot;)))"
-      c_user_include_directories="../../src;$(rootDir)/hw;$(rootDir)/src;$(lpcDir)//inc;$(lpcDir)//inc/config_43xx"
+      c_user_include_directories="../../src;$(rootDir)/hw;$(rootDir)/src;$(lpcDir)//inc;$(rootDir)/lib/SEGGER_RTT/RTT;$(lpcDir)//inc/config_43xx"
       debug_register_definition_file="LPC43xx_Registers.xml"
       debug_target_connection="J-Link"
       gcc_enable_all_warnings="Yes"
@@ -122,11 +122,16 @@
       <file file_name="LPC43xx_Vectors.s" />
       <file file_name="thumb_crt0.s" />
     </folder>
-    <folder
-      Name="segger_rtt"
-      exclude=""
-      filter="*.c;*.h"
-      path="../../../../../lib/segger_rtt"
-      recurse="No" />
+    <folder Name="lib">
+      <folder Name="SEGGER_RTT">
+        <folder Name="RTT">
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT.c" />
+          <file file_name="../../../../../lib/SEGGER_RTT/RTT/SEGGER_RTT_printf.c" />
+        </folder>
+        <folder Name="Syscalls">
+          <file file_name="../../../../../lib/SEGGER_RTT/Syscalls/SEGGER_RTT_Syscalls_SES.c" />
+        </folder>
+      </folder>
+    </folder>
   </project>
 </solution>
diff --git a/examples/host/cdc_msc_hid/src/main.c b/examples/host/cdc_msc_hid/src/main.c
index 0fbbd4534..4200cc5e0 100644
--- a/examples/host/cdc_msc_hid/src/main.c
+++ b/examples/host/cdc_msc_hid/src/main.c
@@ -58,7 +58,7 @@ int main(void)
     cdc_task();
 #endif
 
-#if CFG_TUD_HID
+#if CFG_TUH_HID_KEYBOARD || CFG_TUH_HID_MOUSE
     hid_task();
 #endif
   }
@@ -75,7 +75,7 @@ CFG_TUSB_MEM_SECTION static char serial_in_buffer[64] = { 0 };
 void tuh_mount_cb(uint8_t dev_addr)
 {
   // application set-up
-  printf("\na CDC device  (address %d) is mounted\n", dev_addr);
+  printf("A device with address %d is mounted\r\n", dev_addr);
 
   tuh_cdc_receive(dev_addr, serial_in_buffer, sizeof(serial_in_buffer), true); // schedule first transfer
 }
@@ -83,7 +83,7 @@ void tuh_mount_cb(uint8_t dev_addr)
 void tuh_umount_cb(uint8_t dev_addr)
 {
   // application tear-down
-  printf("\na CDC device (address %d) is unmounted \n", dev_addr);
+  printf("A device with address %d is unmounted \r\n", dev_addr);
 }
 
 // invoked ISR context
@@ -110,27 +110,83 @@ void cdc_task(void)
 // USB HID
 //--------------------------------------------------------------------+
 #if CFG_TUH_HID_KEYBOARD
-void hid_task(void)
+
+uint8_t const keycode2ascii[128][2] =  { HID_KEYCODE_TO_ASCII };
+
+// look up new key in previous keys
+static inline bool find_key_in_report(hid_keyboard_report_t const *p_report, uint8_t keycode)
 {
+  for(uint8_t i=0; i<6; i++)
+  {
+    if (p_report->keycode[i] == keycode)  return true;
+  }
+
+  return false;
+}
+
+static inline void process_kbd_report(hid_keyboard_report_t const *p_new_report)
+{
+  static hid_keyboard_report_t prev_report = { 0, 0, {0} }; // previous report to check key released
+
+  //------------- example code ignore control (non-printable) key affects -------------//
+  for(uint8_t i=0; i<6; i++)
+  {
+    if ( p_new_report->keycode[i] )
+    {
+      if ( find_key_in_report(&prev_report, p_new_report->keycode[i]) )
+      {
+        // exist in previous report means the current key is holding
+      }else
+      {
+        // not existed in previous report means the current key is pressed
+        bool const is_shift =  p_new_report->modifier & (KEYBOARD_MODIFIER_LEFTSHIFT | KEYBOARD_MODIFIER_RIGHTSHIFT);
+        uint8_t ch = keycode2ascii[p_new_report->keycode[i]][is_shift ? 1 : 0];
+        putchar(ch);
+        if ( ch == '\r' ) putchar('\n'); // added new line for enter key
+
+        fflush(stdout); // flush right away, else nanolib will wait for newline
+      }
+    }
+    // TODO example skips key released
+  }
+
+  prev_report = *p_new_report;
+}
 
+CFG_TUSB_MEM_SECTION static hid_keyboard_report_t usb_keyboard_report;
+
+void hid_task(void)
+{
+  uint8_t const addr = 1;
+  if ( tuh_hid_keyboard_is_mounted(addr) )
+  {
+    if ( !tuh_hid_keyboard_is_busy(addr) )
+    {
+      process_kbd_report(&usb_keyboard_report);
+      tuh_hid_keyboard_get_report(addr, &usb_keyboard_report);
+    }
+  }
 }
 
 void tuh_hid_keyboard_mounted_cb(uint8_t dev_addr)
 {
   // application set-up
-  printf("\na Keyboard device (address %d) is mounted\n", dev_addr);
+  printf("A Keyboard device (address %d) is mounted\r\n", dev_addr);
+
+  tuh_hid_keyboard_get_report(dev_addr, &usb_keyboard_report);
 }
 
 void tuh_hid_keyboard_unmounted_cb(uint8_t dev_addr)
 {
   // application tear-down
-  printf("\na Keyboard device (address %d) is unmounted\n", dev_addr);
+  printf("A Keyboard device (address %d) is unmounted\r\n", dev_addr);
 }
 
 // invoked ISR context
 void tuh_hid_keyboard_isr(uint8_t dev_addr, xfer_result_t event)
 {
-
+  (void) dev_addr;
+  (void) event;
 }
 
 #endif
@@ -139,18 +195,20 @@ void tuh_hid_keyboard_isr(uint8_t dev_addr, xfer_result_t event)
 void tuh_hid_mouse_mounted_cb(uint8_t dev_addr)
 {
   // application set-up
-  printf("\na Mouse device (address %d) is mounted\n", dev_addr);
+  printf("A Mouse device (address %d) is mounted\r\n", dev_addr);
 }
 
 void tuh_hid_mouse_unmounted_cb(uint8_t dev_addr)
 {
   // application tear-down
-  printf("\na Mouse device (address %d) is unmounted\n", dev_addr);
+  printf("A Mouse device (address %d) is unmounted\r\n", dev_addr);
 }
 
 // invoked ISR context
 void tuh_hid_mouse_isr(uint8_t dev_addr, xfer_result_t event)
 {
+  (void) dev_addr;
+  (void) event;
 }
 #endif
 
@@ -187,16 +245,23 @@ void print_greeting(void)
       [OPT_OS_FREERTOS]  = "FreeRTOS",
   };
 
-  printf("\n--------------------------------------------------------------------\n");
-  printf("- Host example\n");
-  printf("- if you find any bugs or get any questions, feel free to file an\n");
-  printf("- issue at https://github.com/hathach/tinyusb\n");
-  printf("--------------------------------------------------------------------\n\n");
+  printf("--------------------------------------------------------------------\r\n");
+  printf("- Host example\r\n");
+  printf("- if you find any bugs or get any questions, feel free to file an\r\n");
+  printf("- issue at https://github.com/hathach/tinyusb\r\n");
+  printf("--------------------------------------------------------------------\r\n\r\n");
+
+  printf("This Host demo is configured to support:\r\n");
+  printf("  - RTOS = %s\r\n", rtos_name[CFG_TUSB_OS]);
+
+#if CFG_TUH_CDC
+  printf("  - Communication Device Class\r\n");
+#endif
+
+#if CFG_TUH_MSC
+  printf("  - Mass Storage\r\n");
+#endif
 
-  printf("This Host demo is configured to support:");
-  printf("  - RTOS = %s\n", rtos_name[CFG_TUSB_OS]);
-//  if (CFG_TUH_CDC          ) puts("  - Communication Device Class");
-//  if (CFG_TUH_MSC          ) puts("  - Mass Storage");
 //  if (CFG_TUH_HID_KEYBOARD ) puts("  - HID Keyboard");
 //  if (CFG_TUH_HID_MOUSE    ) puts("  - HID Mouse");
 }
diff --git a/examples/host/cdc_msc_hid/src/msc_app.c b/examples/host/cdc_msc_hid/src/msc_app.c
index 20ac88744..62bd961c1 100644
--- a/examples/host/cdc_msc_hid/src/msc_app.c
+++ b/examples/host/cdc_msc_hid/src/msc_app.c
@@ -35,23 +35,24 @@
 //------------- IMPLEMENTATION -------------//
 void tuh_msc_mounted_cb(uint8_t dev_addr)
 {
-  puts("\na MassStorage device is mounted");
+  printf("A MassStorage device is mounted\r\n");
 
-//  //------------- Disk Information -------------//
-//  // SCSI VendorID[8] & ProductID[16] from Inquiry Command
-//  uint8_t const* p_vendor  = tuh_msc_get_vendor_name(dev_addr);
-//  uint8_t const* p_product = tuh_msc_get_product_name(dev_addr);
-//
-//  for(uint8_t i=0; i<8; i++) putchar(p_vendor[i]);
-//
-//  putchar(' ');
-//  for(uint8_t i=0; i<16; i++) putchar(p_product[i]);
-//  putchar('\n');
-//
-//  uint32_t last_lba, block_size;
-//  tuh_msc_get_capacity(dev_addr, &last_lba, &block_size);
-//  printf("Disk Size: %d MB\n", (last_lba+1)/ ((1024*1024)/block_size) );
-//  printf("LBA 0-0x%X  Block Size: %d\n", last_lba, block_size);
+  //------------- Disk Information -------------//
+  // SCSI VendorID[8] & ProductID[16] from Inquiry Command
+  uint8_t const* p_vendor  = tuh_msc_get_vendor_name(dev_addr);
+  uint8_t const* p_product = tuh_msc_get_product_name(dev_addr);
+
+  for(uint8_t i=0; i<8; i++) putchar(p_vendor[i]);
+
+  putchar(' ');
+  for(uint8_t i=0; i<16; i++) putchar(p_product[i]);
+  putchar('\n');
+
+  uint32_t last_lba = 0;
+  uint32_t block_size = 0;
+  tuh_msc_get_capacity(dev_addr, &last_lba, &block_size);
+  printf("Disk Size: %ld MB\r\n", (last_lba+1)/ ((1024*1024)/block_size) );
+  printf("LBA 0-0x%lX  Block Size: %ld\r\n", last_lba, block_size);
 //
 //  //------------- file system (only 1 LUN support) -------------//
 //  uint8_t phy_disk = dev_addr-1;
@@ -81,7 +82,8 @@ void tuh_msc_mounted_cb(uint8_t dev_addr)
 
 void tuh_msc_unmounted_cb(uint8_t dev_addr)
 {
-  puts("\na MassStorage device is unmounted");
+  (void) dev_addr;
+  printf("A MassStorage device is unmounted\r\n");
 
 //  uint8_t phy_disk = dev_addr-1;
 //
diff --git a/examples/host/cdc_msc_hid/src/tusb_config.h b/examples/host/cdc_msc_hid/src/tusb_config.h
index aa259dafd..6604623b1 100644
--- a/examples/host/cdc_msc_hid/src/tusb_config.h
+++ b/examples/host/cdc_msc_hid/src/tusb_config.h
@@ -40,9 +40,9 @@
 #endif
 
 #if CFG_TUSB_MCU == OPT_MCU_LPC43XX || CFG_TUSB_MCU == OPT_MCU_LPC18XX || CFG_TUSB_MCU == OPT_MCU_MIMXRT10XX
-#define CFG_TUSB_RHPORT0_MODE       (OPT_MODE_HOST | OPT_MODE_HIGH_SPEED)
+  #define CFG_TUSB_RHPORT0_MODE       (OPT_MODE_HOST | OPT_MODE_HIGH_SPEED)
 #else
-#define CFG_TUSB_RHPORT0_MODE       OPT_MODE_HOST
+  #define CFG_TUSB_RHPORT0_MODE       OPT_MODE_HOST
 #endif
 
 #define CFG_TUSB_OS                 OPT_OS_NONE
@@ -69,29 +69,16 @@
 // CONFIGURATION
 //--------------------------------------------------------------------
 
-#define CFG_TUH_HUB                 1
+#define CFG_TUH_HUB                 0
 #define CFG_TUH_CDC                 1
-#define CFG_TUH_HID_KEYBOARD        0
-#define CFG_TUH_HID_MOUSE           0
+#define CFG_TUH_HID_KEYBOARD        1
+#define CFG_TUH_HID_MOUSE           1
 #define CFG_TUSB_HOST_HID_GENERIC   0 // (not yet supported)
-#define CFG_TUH_MSC                 0
+#define CFG_TUH_MSC                 1
+#define CFG_TUH_VENDOR              0
 
 #define CFG_TUSB_HOST_DEVICE_MAX    (CFG_TUH_HUB ? 5 : 1) // normal hub has 4 ports
 
-//------------- CLASS -------------//
-#define CFG_TUD_CDC                 0
-#define CFG_TUD_MSC                 0
-#define CFG_TUD_HID                 0
-#define CFG_TUD_VENDOR              0
-
-// CDC FIFO size of TX and RX
-#define CFG_TUD_CDC_RX_BUFSIZE      64
-#define CFG_TUD_CDC_TX_BUFSIZE      64
-
-// MSC Buffer size of Device Mass storage
-#define CFG_TUD_MSC_BUFSIZE         512
-
-
 #ifdef __cplusplus
  }
 #endif
diff --git a/examples/make.mk b/examples/make.mk
index b7917987e..6743044fd 100644
--- a/examples/make.mk
+++ b/examples/make.mk
@@ -84,7 +84,6 @@ ifeq ($(LOGGER),rtt)
   RTT_SRC = lib/SEGGER_RTT
   CFLAGS += -DLOGGER_RTT -DSEGGER_RTT_MODE_DEFAULT=SEGGER_RTT_MODE_BLOCK_IF_FIFO_FULL
   INC   += $(TOP)/$(RTT_SRC)/RTT
-  SRC_C += $(RTT_SRC)/RTT/SEGGER_RTT_printf.c
   SRC_C += $(RTT_SRC)/RTT/SEGGER_RTT.c
 else ifeq ($(LOGGER),swo)
   CFLAGS += -DLOGGER_SWO
diff --git a/examples/readme.md b/examples/readme.md
deleted file mode 100644
index f6cd380b6..000000000
--- a/examples/readme.md
+++ /dev/null
@@ -1,104 +0,0 @@
-# Examples
-
-## Clone this repo
-
-```
-$ git clone https://github.com/hathach/tinyusb tinyusb
-$ cd tinyusb
-```
-
-## Fetch submodule MCUs drivers
-
-TinyUSB examples includes external repos aka submodules to provide low-level MCU peripheral's driver to compile with. Therefore we will firstly fetch those mcu driver repo by running this command in the top folder repo
-
-```
-$ git submodule update --init --recursive
-```
-
-It will takes a bit of time due to the number of supported MCUs, luckily we only need to do this once. Or if you only want to test with a specific mcu, you could only update its driver submodule 
-
-## Build
-
-[Here is the list of supported Boards](docs/boards.md) that should work out of the box with provided examples (hopefully).
-To build example, first change directory to example folder. 
-
-```
-$ cd examples/device/cdc_msc
-```
-
-Then compile with `make BOARD=[your_board] all`, for example
-
-```
-$ make BOARD=feather_nrf52840_express all
-```
-
-**Port Selection**
-
-If a board has several ports, one port is chosen by default in the individual board.mk file. Use option `PORT=x` To choose another port. For example to select the HS port of a STM32F746Disco board, use:
-
-```
-$ make BOARD=stm32f746disco PORT=1 all
-```
-
-**Port Speed**
-
-A MCU can support multiple operational speed. By default, the example build system will use the fastest supported on the board. Use option `SPEED=full/high` e.g To force F723 operate at full instead of default high speed
-
-```
-$ make BOARD=stm32f746disco SPEED=full all
-```
-
-### Debug
-
-To compile for debugging with debug symbols add `DEBUG=1`, for example
-
-```
-$ make BOARD=feather_nrf52840_express DEBUG=1 all
-```
-
-#### Log
-
-Should you have an issue running example and/or submitting an bug report. You could enable TinyUSB built-in debug logging with optional `LOG=`. LOG=1 will only print out error message, LOG=2 print more information with on-going events. LOG=3 or higher is not used yet. 
-
-```
-$ make BOARD=feather_nrf52840_express LOG=2 all
-```
-
-#### Logger
-
-By default log message is printed via on-board UART which is slow and take lots of CPU time comparing to USB speed. If your board support on-board/external debugger, it would be more efficient to use it for logging. There are 2 protocols: 
-
-- `LOGGER=rtt`: use [Segger RTT protocol](https://www.segger.com/products/debug-probes/j-link/technology/about-real-time-transfer/)   
-  - Cons: requires jlink as the debugger.
-  - Pros: work with most if not all MCUs
-  - Software viewer is JLink RTT Viewer/Client/Logger which is bundled with JLink driver package.
-- `LOGGER=swo`: Use dedicated SWO pin of ARM Cortex SWD debug header.
-  - Cons: only work with ARM Cortex MCUs minus M0
-  - Pros: should be compatible with more debugger that support SWO.
-  - Software viewer should be provided along with your debugger driver.
-
-```
-$ make BOARD=feather_nrf52840_express LOG=2 LOGGER=rtt all
-$ make BOARD=feather_nrf52840_express LOG=2 LOGGER=swo all
-```
-
-## Flash
-
-`flash` target will use the default on-board debugger (jlink/cmsisdap/stlink/dfu) to flash the binary, please install those support software in advance. Some board use bootloader/DFU via serial which is required to pass to make command
-
-```
-$ make BOARD=feather_nrf52840_express flash
-$ make SERIAL=/dev/ttyACM0 BOARD=feather_nrf52840_express flash
-```
-
-Since jlink can be used with most of the boards, there is also `flash-jlink` target for your convenience.
-
-```
-$ make BOARD=feather_nrf52840_express flash-jlink
-```
-
-Some board use uf2 bootloader for drag & drop in to mass storage device, uf2 can be generated with `uf2` target
-
-```
-$ make BOARD=feather_nrf52840_express all uf2
-```
diff --git a/examples/rules.mk b/examples/rules.mk
index dacb81363..37e0e7a19 100644
--- a/examples/rules.mk
+++ b/examples/rules.mk
@@ -33,6 +33,7 @@ SRC_C += \
 	src/common/tusb_fifo.c \
 	src/device/usbd.c \
 	src/device/usbd_control.c \
+	src/class/audio/audio_device.c \
 	src/class/cdc/cdc_device.c \
 	src/class/dfu/dfu_rt_device.c \
 	src/class/hid/hid_device.c \
@@ -147,6 +148,8 @@ else
   JLINKEXE = JLinkExe
 endif
 
+JLINK_IF ?= swd
+
 # Flash using jlink
 flash-jlink: $(BUILD)/$(BOARD)-firmware.hex
 	@echo halt > $(BUILD)/$(BOARD).jlink
@@ -161,4 +164,9 @@ flash-jlink: $(BUILD)/$(BOARD)-firmware.hex
 flash-stlink: $(BUILD)/$(BOARD)-firmware.elf
 	STM32_Programmer_CLI --connect port=swd --write $< --go
 
+# flash with pyocd
+flash-pyocd: $(BUILD)/$(BOARD)-firmware.hex
+	pyocd flash -t $(PYOCD_TARGET) $<
+	pyocd reset -t $(PYOCD_TARGET)
+
 endif # Make target