rotem segev

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6 years, 6 months ago.

LPUART1 not working on DISCO L476

Hi I am developed a board based on the DISCO L476 and after porting it to VisualGDB everything works great. The only thing that doesn't work is LPUART1. I hooked it to PB10, PB11 but whenever I declare the port in my code and download it, the program hangs and doesn't even start:

Serial RS232(PB_11, PB_10);

If I remove this line, the code works great (but I can't use this port)

I changed the pin definitions in PeripheralPins.c so PB10 and PB11 will function as the LPUART TX and RX pins: (I added the lines)

const PinMap PinMap_UART_RX[] = { {PB_10, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)},

//

const PinMap PinMap_UART_TX[] = { {PB_11, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)},

but it still doesn't work. Any ideas?

1 Answer

Austin Blackstone
6 years, 6 months ago.

Rotem,

In the peripheralpins.c file the chunks look like this 

//*** SERIAL ***

const PinMap PinMap_UART_TX[] = {
    {PA_0,  UART_4, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)},
    {PA_2,  UART_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)}, // Warning: UART_2 already used by STDIO
    {PA_9,  UART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)},
    {PB_6,  UART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)},
    {PB_10, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)},
//  {PB_11, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)}, // Warning: Already used by UART_RX
    {PC_1,  LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)},
    {PC_4,  UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)},
    {PC_10, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)},
//  {PC_10, UART_4, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)},
    {PC_12, UART_5, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART5)},
    {PD_5,  UART_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)}, // STDIO_TX
    {NC,    NC,     0}
};

const PinMap PinMap_UART_RX[] = {
    {PA_1,  UART_4, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)},
    {PA_3,  UART_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)}, // Warning: UART_2 already used by STDIO
    {PA_10, UART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)},
    {PB_7,  UART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)},
//  {PB_10, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)}, // Warning: Already used by UART_TX
    {PB_11, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)},
    {PC_0,  LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)},
    {PC_5,  UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)},
    {PC_11, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)},
//  {PC_11, UART_4, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)},
    {PD_2,  UART_5, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART5)},
    {PD_6,  UART_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)}, // STDIO_RX
    {NC,    NC,     0}
};

It looks like the pins are already in use. So if you are going to enable them then I suggest you also disable the pre-existing uses. So for the TX array this would be removing line 8 above, and for the RX array removing line 25 above.

If this doesnt solve your problem, then I would suggest asking the question on the board page (https://os.mbed.com/questions/create?url=/platforms/ST-Discovery-L476VG/) so ST can answer you directly.

Accepted Answer

Thank you very much for your answer. I already cleared all instances of PB_11 and PB_10 on peripheralpins.c so It's not the cause of the problem:

const PinMap PinMap_UART_TX[] = { {PA_0, UART_4, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)}, {PA_2, UART_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)}, Warning: UART_2 already used by STDIO {PA_9, UART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)}, {PB_6, UART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)}, {PB_10, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)}, {PB_11, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)}, Warning: Already used by UART_RX {PC_1, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)}, {PC_4, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)}, {PC_10, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)}, {PD_8, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)}, {PC_10, UART_4, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)}, {PC_12, UART_5, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART5)}, {PD_5, UART_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)}, STDIO_TX {NC, NC, 0} };

const PinMap PinMap_UART_RX[] = { {PA_1, UART_4, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)}, {PA_3, UART_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)}, Warning: UART_2 already used by STDIO {PA_10, UART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)}, {PB_7, UART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART1)}, {PB_10, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)}, Warning: Already used by UART_TX {PB_11, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)}, {PC_0, LPUART_1, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_LPUART1)}, {PC_5, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)}, {PC_11, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)}, {PD_9, UART_3, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART3)}, {PC_11, UART_4, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART4)}, {PD_2, UART_5, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF8_UART5)}, {PD_6, UART_2, STM_PIN_DATA(STM_MODE_AF_PP, GPIO_PULLUP, GPIO_AF7_USART2)}, STDIO_RX {NC, NC, 0}

Thanks, I will post it on the board's page.

posted by rotem segev 31 Oct 2017