3 files changed, 15 insertions, 3 deletions
diff --git a/examples/device/board_test/src/CMakeLists.txt b/examples/device/board_test/src/CMakeLists.txt
index e4e1f4e9a..37625f441 100644
--- a/examples/device/board_test/src/CMakeLists.txt
+++ b/examples/device/board_test/src/CMakeLists.txt
@@ -2,7 +2,7 @@
 idf_component_register(SRCS "main.c"
                     INCLUDE_DIRS "."
                     REQUIRES freertos soc)
-                    
+
 file(TO_NATIVE_PATH "${TOP}/hw/bsp/${FAMILY}/boards/${BOARD}/board.cmake" board_cmake)
 
 if(EXISTS ${board_cmake})
diff --git a/examples/device/board_test/src/main.c b/examples/device/board_test/src/main.c
index 207ca6294..3f8d55c52 100644
--- a/examples/device/board_test/src/main.c
+++ b/examples/device/board_test/src/main.c
@@ -1,4 +1,4 @@
-/* 
+/*
  * The MIT License (MIT)
  *
  * Copyright (c) 2019 Ha Thach (tinyusb.org)
@@ -56,7 +56,7 @@ int main(void)
   {
     uint32_t interval_ms = board_button_read() ? BLINK_PRESSED : BLINK_UNPRESSED;
 
-    // Blink every interval ms
+    // Blink and print every interval ms
     if ( !(board_millis() - start_ms < interval_ms) )
     {
       board_uart_write(HELLO_STR, strlen(HELLO_STR));
@@ -66,6 +66,13 @@ int main(void)
       board_led_write(led_state);
       led_state = 1 - led_state; // toggle
     }
+
+    // echo
+    uint8_t ch;
+    if ( board_uart_read(&ch, 1) > 0 )
+    {
+      board_uart_write(&ch, 1);
+    }
   }
 }
 
diff --git a/examples/device/board_test/src/tusb_config.h b/examples/device/board_test/src/tusb_config.h
index 5aea4fd2c..2c2eb5280 100644
--- a/examples/device/board_test/src/tusb_config.h
+++ b/examples/device/board_test/src/tusb_config.h
@@ -30,6 +30,11 @@
  extern "C" {
 #endif
 
+// board_test example is special example that doesn't enable device or host stack
+// This can cause some TinyUSB API missing, this define hack to allow us to fill those API
+// to pass the compilation process
+#define tud_int_handler(x)
+
 //--------------------------------------------------------------------
 // COMMON CONFIGURATION
 //--------------------------------------------------------------------