Blink example for STM32L552 Nucleo board

[krook]

Hi!

I am trying to run a simple blink example using the STM32L552 Nucleo board, but I can't seem to figure it out. Any help in figuring out what my problem is would be very helpful. I've tried looking at the data sheet to figure out what the SRAM-boundaries are etc, but I must have gotten something wrong.

I am using the CMSIS stuff. The program is simply supposed to blink on of the LEDs, but nothing happens.

Here is startup.c:

#define SRAM_START (0x20000000UL)
#define SRAM_SIZE (32U * 256U)
#define SRAM_END (SRAM_START + SRAM_SIZE)
#define STACK_POINTER_INIT_ADDRESS (SRAM_END)

#include <stdint.h>
#define VECTOR_SIZE_WORDS 464

void default_handler(void);
void reset_handler(void);

void nmi_handler(void) __attribute__((weak, alias("default_handler")));
void hard_handler(void) __attribute__((weak, alias("default_handler")));
void mem_handler(void) __attribute__((weak, alias("default_handler")));
void bus_handler(void) __attribute__((weak, alias("default_handler")));
void usage_handler(void) __attribute__((weak, alias("default_handler")));
void sv_handler(void) __attribute__((weak, alias("default_handler")));
void debug_handler(void) __attribute__((weak, alias("default_handler")));
void pend_handler(void) __attribute__((weak, alias("default_handler")));
void sys_handler(void) __attribute__((weak, alias("default_handler")));

uint32_t isr_vector[VECTOR_SIZE_WORDS] __attribute__((section(".isr_vector"))) = {
    STACK_POINTER_INIT_ADDRESS,
    (uint32_t)&reset_handler,
    (uint32_t)&nmi_handler,
    (uint32_t)&hard_handler,
    (uint32_t)&mem_handler,
    (uint32_t)&bus_handler,
    (uint32_t)&usage_handler,
    0,
    0,
    0,
    0,
    (uint32_t)&sv_handler,
    (uint32_t)&debug_handler,
    0,
    (uint32_t)&pend_handler,
    (uint32_t)&sys_handler,
    // add more handlers as wanted
};

void default_handler(void) {
    while(1);
}

extern uint32_t _etext, _sdata, _edata, _sbss, _ebss;
void main(void);

void reset_handler(void) {
    // Copy .data from FLASH to SRAM
    uint32_t data_size = (uint32_t)&_edata - (uint32_t)&_sdata;
    uint8_t *flash_data = (uint8_t*) &_etext;
    uint8_t *sram_data = (uint8_t*) &_sdata;
  
    for (uint32_t i = 0; i < data_size; i++)
    {
      sram_data[i] = flash_data[i];
    }

    // Zero-fill .bss section in SRAM
    uint32_t bss_size = (uint32_t)&_ebss - (uint32_t)&_sbss;
    uint8_t *bss = (uint8_t*) &_sbss;

    for (uint32_t i = 0; i < bss_size; i++)
    {
      bss[i] = 0;
    }
  
    main();
}

 And here is my main.c:

#include <stdint.h>
#include "stm32l5xx.h"

#define LED_PIN 9 // PA9 should be one of the LEDs!

void main(void) {
    // enable the peripheral clock
    RCC->AHB2ENR |= (1 << RCC_AHB2ENR_GPIOAEN_Pos);

    volatile uint32_t dummy;
    dummy = RCC->AHB2ENR;
    dummy = RCC->AHB2ENR;

    // set PA9 as output
    GPIOA->MODER |= (1 << GPIO_MODER_MODE9_Pos);
    
    // toggle the pin on and off
    while(1) {
        GPIOA->ODR ^= (1 << LED_PIN);
        for (uint32_t i = 0; i < 1000000; i++);
    }
}

 I've managed to put together this linker script by following a tutorial online:

ENTRY(reset_handler)

MEMORY
{
    FLASH (rx): ORIGIN = 0x8000000, LENGTH = 512K
    SRAM (rwx): ORIGIN = 0x20000000, LENGTH = 1024K
}

SECTIONS
{
    .isr_vector :
    {
        KEEP(*(.isr_vector))
    } >FLASH

    .text :
    {
        . = ALIGN(4);
        *(.text)
        *(.rodata)
        . = ALIGN(4);
        _etext = .;
    } >FLASH

    .data :
    {
        . = ALIGN(4);
        _sdata = .;
        *(.data)
        . = ALIGN(4);
        _edata = .;
    } >SRAM AT> FLASH

    .bss :
    {
        . = ALIGN(4);
        _sbss = .;
        *(.bss)
        . = ALIGN(4);
        _ebss = .;
    } >SRAM
}

 I manage to compile this without warning and flash my device using `openocd`, but the board is not blinking.

This document might be helpful -- it is from where I've collected information: file:///home/robert/Downloads/dm00346336-stm32l552xx-and-stm32l562xx-advanced-arm-based-32-bit-mcus-stmicroelectronics.pdf

[krook]

Lol I didn't check that the link I posted was actually the correct one... this is of course the link that I wanted to provide: https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://www.st.com/resource/en/reference_manual/dm00346336-stm32l552xx-and-stm32l562xx-advanced-arm-based-32-bit-mcus-stmicroelectronics.pdf&ved=2ahUKEwjj0qzopsqIAxW2FBAIHfZXC9QQFnoECBQQAQ&usg=AOvVaw2Xwv5137qa2OFrClStJ4Xl

I've also attached the document to this reply. It is the STM32L552 reference manual.

[SofLit]

hello,

Need to check the registers content in the debugger versus what you are suspecting.