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serial port not work

Ranjeet Singh
Senior

i am using stm32l4r5zi microcontroller .i have enabled all uart port 1,2,3,4,5 but this is not showing data on usb serial port .does l4r5 usb serial port not supporting ?


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10 REPLIES 10
Ranjeet Singh
Senior

i have also change the baud rate in LPUART1 ,(209700 to 115200 ) but data not showing

gbm
Lead III

What board? How is your UART conected to your PC? Check the schematics; you will see which pins are connected to the UART interface. Setup the UART in CubeMX, double check that the proper pins are selected for it.

My STM32 stuff on github - compact USB device stack and more: https://github.com/gbm-ii/gbmUSBdevice
AScha.3
Chief II

>i have enabled all uart port 1,2,3,4,5 

>is not showing data on usb serial port 

what now ?? use serial port on pin..xx OR usb /CDC driver as usb device ?

If you feel a post has answered your question, please click "Accept as Solution".

Explanation and context hard to follow.

Perhaps look at pin output with a scope.

Guessing a NUCLEO board.

Why using 7-bit mode?

Mismatch in bit and baud modes of terminal vs UART.

​Write a string output function that computes length.

I​f pins on GPIOG bank, make sure VCCIO2 enabled.

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Up vote any posts that you find helpful, it shows what's working..
WQ
Associate III

Don't use internal HSI/MSI RC clocks with that high baud-rate UART or try to slow down (to 9600 or lower). If you are using NUCLEO-L4R5ZI, the HSE oscillator is not populated. You have to use the MCO output from the ST-Link by closing SB109 and SB148 and setting HSE in bypass. That is what I experienced not a long time ago on the other L4 NUCLEO board. -wq

gbm
Lead III

Not a problem. MSI may be synchronized to LSE, which is populated on Nucleo boards.

My STM32 stuff on github - compact USB device stack and more: https://github.com/gbm-ii/gbmUSBdevice

stm32l4r5zi 

if i will use serialch340 on pins then it work

question is this why usb port not worj will othere controlller work