STM32F427 Can spitting random garbage

[Just Matt]

Posted on February 04, 2016 at 16:20

Used the STMCubeMX to generate the code. STM32F429I disco board, CAN running at 500k.

I added a very simple to the loop,

hcan1.pTxMsg->StdId = 0x11;
hcan1.pTxMsg->ExtId = 0x01;
hcan1.pTxMsg->IDE = CAN_ID_STD;
hcan1.pTxMsg->RTR = CAN_RTR_DATA;
hcan1.pTxMsg->DLC = 2;
hcan1.pTxMsg->Data[0] = 0xCA;
hcan1.pTxMsg->Data[1] = 0xFF;
if
(HAL_CAN_Transmit(&hcan1, 10) != HAL_OK)
{
/* Error */
asm(
''nop''
);
}

Then what is received by my Can monitor is 0x240 A6 A7 03 CE Here is a screenshot of the object It almost feels like I have a clock issue. But i'm fairly certain I have it setup right.

void
SystemClock_Config(
void
)
{
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_ClkInitTypeDef RCC_ClkInitStruct;
__PWR_CLK_ENABLE();
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE1);
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
RCC_OscInitStruct.HSEState = RCC_HSE_ON;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
RCC_OscInitStruct.PLL.PLLM = 8;
RCC_OscInitStruct.PLL.PLLN = 336;
RCC_OscInitStruct.PLL.PLLP = RCC_PLLP_DIV2;
RCC_OscInitStruct.PLL.PLLQ = 7;
HAL_RCC_OscConfig(&RCC_OscInitStruct);
RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1
|RCC_CLOCKTYPE_PCLK2;
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_PLLCLK;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV4;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV2;
HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_5);
HAL_SYSTICK_Config(HAL_RCC_GetHCLKFreq()/1000);
HAL_SYSTICK_CLKSourceConfig(SYSTICK_CLKSOURCE_HCLK);
/* SysTick_IRQn interrupt configuration */
HAL_NVIC_SetPriority(SysTick_IRQn, 0, 0);
}
/* CAN1 init function */
void
MX_CAN1_Init(
void
)
{
hcan1.Instance = CAN1;
hcan1.Init.Prescaler = 4;
hcan1.Init.Mode = CAN_MODE_NORMAL;
hcan1.Init.SJW = CAN_SJW_1TQ;
hcan1.Init.BS1 = CAN_BS1_14TQ;
hcan1.Init.BS2 = CAN_BS2_6TQ;
hcan1.Init.TTCM = DISABLE;
hcan1.Init.ABOM = DISABLE;
hcan1.Init.AWUM = DISABLE;
hcan1.Init.NART = DISABLE;
hcan1.Init.RFLM = DISABLE;
hcan1.Init.TXFP = DISABLE;
HAL_CAN_Init(&hcan1);
}

Feedback welcome. I can post up more code if needed.

[Just Matt]

Posted on February 04, 2016 at 17:44

I feel like an idiot.

static
CanTxMsgTypeDef TxMessage;
hcan1.pTxMsg = &TxMessage;