Question
STM32F4 config CAN Filters
Posted on July 26, 2016 at 14:35
Hello there,
For a while now I am trying to configure the CAN filter system to work properly in STM32F4 I have managed to make the system work the way that I have 2 mask filters. Depending on which the CAN ID message is received through FIFO0 or FIFO1. So it seems to be working properly. But not quite... In the HAL CAN RX interrupt routine the filter hit is checked (FMI part from CAN_RDTxR register). Even though messages come to the proper FIFO, the FMI part is always 0. I started playing with the filter ID configuration and FMI started to change, but still it didnt reflect my configured filter number at any point. This is my configuration code:/**
* @brief Configures the Can receiving filter.
* Filter should cover the lower part of upper 16 bit mask and filter.
* @param canData: Pointer to a can conf struct, preconfigured.
* @return HAL_OK if all ok.
*/
HAL_StatusTypeDef can_ConfigRxFilter(canData_t* canData)
{
assert_param(canData);
assert_param(canData->canHandle);
HAL_StatusTypeDef retVal = HAL_OK;
CAN_FilterConfTypeDef sFilterConfig;
// First config unicast filter
sFilterConfig.FilterNumber = canData->objectId;
sFilterConfig.FilterMode = CAN_FILTERMODE_IDMASK;
sFilterConfig.FilterScale = CAN_FILTERSCALE_32BIT;
// TML CAN
uint32_t EXID = canData->canAxisId <<
13
;
uint32_t
STID
=
EXID
& 0x7FF;
uint32_t
EXMASK
=
0xFF
<< 13;
uint32_t
STMASK
=
EXMASK
& 0x7FF;
sFilterConfig.FilterIdHigh = (uint16_t)(((STID << 5) & 0xFFE0) | ((EXID >> 13) & 0x001F));
sFilterConfig.FilterIdLow = (uint16_t)(((EXID <<
3
) & 0xFFF8));
sFilterConfig.FilterMaskIdHigh = (uint16_t)(((STMASK << 5) & 0xFFE0) | ((EXMASK >> 13) & 0x001F));
sFilterConfig.FilterMaskIdLow = (uint16_t)(((EXMASK <<
3
) & 0xFFF8));
sFilterConfig.FilterFIFOAssignment
=
canData
->canRxFifo;
sFilterConfig.FilterActivation = ENABLE;
sFilterConfig.BankNumber = 0;
retVal += HAL_CAN_ConfigFilter(canData->canHandle, &sFilterConfig);
assert_param(!retVal);
return retVal;
}