Merge pull request #3653 from hathach/ch32_warning

add device specific issues

1 files changed, 35 insertions, 0 deletions

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+Device specific known issues and workarounds
+===============================================
+This page lists known issues and workarounds for specific devices.
+
+NXP LPC54600
+----------------
+**Severity: High**
+
+**Not recommended for USB device applications (except high-speed host controller)**
+
+Reference: `LPC54600 Errata Sheet`_
+
+.. _LPC54600 Errata Sheet: https://www.nxp.com/docs/en/errata/ES_LPC546XX.pdf
+
+The LPC54600 series have a very buggy USB controller, with 17 issues listed in the errata which is more than half of the total issues.
+
+Most severe issues are:
+
+- USB.2: In USB high-speed device mode, the NBytes field is not correct after BULK IN transfer
+- USB.5: In USB full-speed host mode, linked list on done queue is broken.
+- USB.15: USB high-speed device in endpoint TX data corruption
+
+WCH CH32F20x/CH32V20x/CH32V30x
+---------------------------------
+**Severity: Medium**
+
+**Not recommended for USB audio applications**
+
+Reference: `CH32V30X Reference Manual`_ USBFS/USBHS controller chapter
+
+.. _CH32V30X Reference Manual: https://www.wch-ic.com/downloads/CH32FV2x_V3xRM_PDF.html
+
+Data corruption may occur on isochronous endpoints. Due to the lacking of FIFO for interrupt status registers, later completed transfer will overwrite `INT_ST` and `RX_LEN` register if previous transfer processing is not completed.
+
+Other types of transfers are not affected.