Not getting to repl via stlink on nucleo f401re

[ramprao]

I just got a nucleo f401re. I was able to flash micropython via the st-flash (built in stlink). But not able to access the board filesystem/repl on the usb port using both rshell and mpremote.

[davefes]

On the WeACT BlackPill STM32F411CE the repl is available on UART1 (A9 and A10) even though it has a USB-C connector. Maybe, the same applies to your board?

[ramprao]

Thanks Dave.
I looked at the mpconfigport.h and UART2 is being used for this board.

I also tried an stm32cubeide program to access the uart and not able to see it there as well. So puzzled.

[davefes]

The mpconfigboard.h that I am using has:

// UART config, 
// 12.5 Mbit/s for USART1 and USART6
// 6.25 Mbit/s for USART2
// Not defining the NAMEs reduces firmware size
// #define MICROPY_HW_UART1_NAME       "USART1"
#define MICROPY_HW_UART1_TX         (pin_A9) // Valid: PA9, PA15, PB6
#define MICROPY_HW_UART1_RX         (pin_A10) // Valid: PA10, PB3, PB7
// #define MICROPY_HW_UART2_NAME       "USART2"
#define MICROPY_HW_UART2_TX         (pin_A2) // Valid: PA2
#define MICROPY_HW_UART2_RX         (pin_A3) // Valid: PA3
// #define MICROPY_HW_UART6_NAME       "USART6"
#define MICROPY_HW_UART6_TX         (pin_A11) // Valid: PA11
#define MICROPY_HW_UART6_RX         (pin_A12) // Valid: PA12

#define MICROPY_HW_UART_REPL        PYB_UART_1
#define MICROPY_HW_UART_REPL_BAUD   115200

I think define MICROPY_HW_UART_REPL PYB_UART_1 is what is needed ... at least for me.

[ramprao]

For my board, its defined as PYB_UART_2. I'll try and rebuild the FW with the REPL UART and connect via USB/UART device and see if there's any luck with it.

[davefes]

Good luck. I am working with this distro:
https://github.com/nspsck/STM32F411CEU6_BlackPill_Micropython
maybe the instructions help.

[ramprao]

Thanks for that repo. Will look at it.

[ramprao]

Thanks for that tip. For my board in the official repo, there's no UART1. After defining it, i had to change the Pins from what's given above. A9/A10 didn't work for me but B6/A10 did. I also tried UART6 but no luck there as well.

What's odd is that the UART2 works via the STLINK for STM32CubeIDE.

[victorallume]

Which USB port are you plugged in to?

[ramprao]

I'm connected to the Mini USB port which is also the STLink port for this board. From what I can see of the config files, the REPL is supposed to be available on this UART.