FreeRTOS libopencm3 blink

queue_test gdb

   ┌──rtos/queue.c─────────────────────────────────────────────────────────────────────────────────────┐
   │1719                            }                                                                  │
   │1720                    }                                                                          │
   │1721                    #endif /* configUSE_MUTEXES */                                             │
   │1722            }                                                                                  │
   │1723            else if( xPosition == queueSEND_TO_BACK )                                          │
   │1724            {                                                                                  │
   │1725                    ( void ) memcpy( ( void * ) pxQueue->pcWriteTo, pvItemToQueue, ( size_t ) p│
B+ │1726                    pxQueue->pcWriteTo += pxQueue->uxItemSize;                                 │
  >│1727                    if( pxQueue->pcWriteTo >= pxQueue->pcTail ) /*lint !e946 MISRA exception ju│
   │1728                    {                                                                          │
   │1729                            pxQueue->pcWriteTo = pxQueue->pcHead;                              │
   │1730                    }                                                                          │
   │1731                    else                                                                       │
   │1732                    {                                                                          │
   │1733                            mtCOVERAGE_TEST_MARKER();                                          │
   │1734                    }                                                                          │
   ┌───────────────────────────────────────────────────────────────────────────────────────────────────┐
   │0x80005ea <prvCopyDataToQueue+22>       str    r5, [r4, #4]                                        │
   │0x80005ec <prvCopyDataToQueue+24>       adds   r6, #1                                              │
   │0x80005ee <prvCopyDataToQueue+26>       str    r6, [r4, #56]   ; 0x38                              │
   │0x80005f0 <prvCopyDataToQueue+28>       pop    {r4, r5, r6, pc}                                    │
   │0x80005f2 <prvCopyDataToQueue+30>       cbnz   r5, 0x8000610 <prvCopyDataToQueue+60>               │
   │0x80005f4 <prvCopyDataToQueue+32>       ldr    r0, [r0, #8]                                        │
   │0x80005f6 <prvCopyDataToQueue+34>       bl     0x8001184 <memcpy>                                  │
B+ │0x80005fa <prvCopyDataToQueue+38>       ldr    r3, [r4, #8]                                        │
   │0x80005fc <prvCopyDataToQueue+40>       ldr    r2, [r4, #64]   ; 0x40                              │
   │0x80005fe <prvCopyDataToQueue+42>       add    r3, r2                                              │
   │0x8000600 <prvCopyDataToQueue+44>       ldr    r2, [r4, #4]                                        │
   │0x8000602 <prvCopyDataToQueue+46>       str    r3, [r4, #8]                                        │
  >│0x8000604 <prvCopyDataToQueue+48>       cmp    r3, r2                                              │
   │0x8000606 <prvCopyDataToQueue+50>       bcc.n  0x800060c <prvCopyDataToQueue+56>                   │
   │0x8000608 <prvCopyDataToQueue+52>       ldr    r3, [r4, #0]                                        │
   │0x800060a <prvCopyDataToQueue+54>       str    r3, [r4, #8]                                        │
   └───────────────────────────────────────────────────────────────────────────────────────────────────┘



(gdb) bt
#0  blocking_handler () at ../../cm3/vector.c:103
#1  <signal handler called>
#2  0x0800048c in prvPortStartFirstTask () at rtos/port.c:270
#3  0x080005c6 in xPortStartScheduler () at rtos/port.c:350
Backtrace stopped: Cannot access memory at address 0x20005004

tasks_blink.c

#include <FreeRTOS.h>
#include <libopencm3/stm32/gpio.h>
#include <libopencm3/stm32/rcc.h>
#include <task.h>

static void
task_on(void *args __attribute__((unused)))
{
  while (1)
  {
    vTaskDelay(pdMS_TO_TICKS(600));
    gpio_clear(GPIOC, GPIO13);
  }
}

static void
task_off(void *args __attribute__((unused)))
{
  while (1)
  {
    vTaskDelay(pdMS_TO_TICKS(1000));
    gpio_set(GPIOC, GPIO13);
  }
}

int
main(void)
{
  rcc_clock_setup_in_hse_8mhz_out_72mhz();

  // Blue-Pill led
  rcc_periph_clock_enable(RCC_GPIOC);
  gpio_set_mode(
    GPIOC,
    GPIO_MODE_OUTPUT_2_MHZ,
    GPIO_CNF_OUTPUT_PUSHPULL,
    GPIO13);
  gpio_set(GPIOC, GPIO13); // Turn off (polarity of the led is inversed!)

  xTaskCreate(task_on, "ON", 200, NULL, configMAX_PRIORITIES-1, NULL);
  xTaskCreate(task_off, "OFF", 200, NULL, configMAX_PRIORITIES-1, NULL);
  vTaskStartScheduler();
  while(1);
  return 0;
}