I have an issue with the DebugDongle when used as a USB to USART bridge. I'm using it extensively and it never fails if the COM port (from the PC point of view) is never closed. But if we close the COM port there is a condition where the buffer sent back to the PC is in fact the previous one (as if the double buffer is not changing page, or changing 2 times ?).
Let me explain how you can replicate the issue: tie together UART Rx and UART Tx so everything is echoed back to the PC. Now I made a application which sends a random number of bytes between 2 to 64 every 100ms and verifies that the received content is the same as what we sent. As said earlier if the COM port is never closed then the application never fails.
Now whenever the number of bytes is equal to 25 (arbitrary can be anything) I choose to close the COM port, wait 100ms, open it again, wait 200ms and start again to send random number of bytes. In some cases the dongle will eventually fail and always send the same buffer (albeit the number of bytes being right).

Hello!

I am getting the error below when i try to compile:

mkdir build_200_200
/usr/bin/arm-none-eabi-gcc -c -mcpu=cortex-m4 -mthumb -mfloat-abi=soft -DUSBD_VID=0x200 -DUSBD_PID=0x200 -DHW_REV= -IBSP -IApp -ICharger -ISensor -IVCP -IHidReportDef/include -IUSBDevice/Include -IUSBDevice/PDs/STM32_XPD -ISTM32_XPD/CMSIS/Include -ISTM32_XPD/CMSIS/Device/ST/STM32F4xx/Include -ISTM32_XPD/STM32F4_XPD/inc -O3 -Wall -fdata-sections -ffunction-sections -std=gnu11 -MMD -MP -MF"build_200_200/bsp_usart.d" -MT"build_200_200/bsp_usart.d" -Wa,-a,-ad,-alms=build_200_200/bsp_usart.lst BSP/bsp_usart.c -o build_200_200/bsp_usart.o
In file included from BSP/bsp_usart.c:23:0:
BSP/bsp_io.h:34:13: error: operator '>' has no left operand
#if (HW_REV > 0xA)

Hi !
I'm having an issue with the VCP part of the dongle.
When I'm sending 'U' over a terminal like putty, and looking at the scope output on PA2 (USART2_TX), I can see that the last bit is missing because I receive 0xD5 instead of 0x55. At first I thought it was the _WFI instruction in the main while loop that was happening too fast, but putting it in comment didn't solve the issue. Then I looked in the USART_prvDmaTransmitRedirect function and there is no check of the TC flag of USART, which needs to be checked before deactivating the DMA. Do you have any idea on this ?

Hi,

Thank you for the correction made to the VCP, I will test them as soon as possible and update you on the outcome.
On a side note, do you happen to have by any chance a driver file for the dongle for win 8 and older ?
On my win 10 PC everything is working as it should, but on some older machine I tried the ST VCP driver but it failed to send back the content of the UART to the USB pipe.
Any idea ?