Hi, 我的代码在附件里，现在我这边只有一块开发板RT1064的开发板MIMXRT1064-EVK，我想用Loopback模式来验证我自己写的驱动，我的思路是第一步调通最基本的loopback模式，然后再把我自己写的驱动逻辑加进来，我使用的是CAN2，loopback模式实现如下：
1、管脚配置
2、初始化
static void flexCanTestInit(void)
{
flexcan_config_t flexcanConfig;
flexcan_rx_mb_config_t mbConfig;
/*Clock setting for FLEXCAN*/
CLOCK_SetMux(kCLOCK_CanMux, FLEXCAN_CLOCK_SOURCE_SELECT);
CLOCK_SetDiv(kCLOCK_CanDiv, FLEXCAN_CLOCK_SOURCE_DIVIDER);
NVIC_SetPriority(CAN2_IRQn, 4);
// PRINTF("\r\n==FlexCAN loopback example -- Start.==\r\n\r\n");
FLEXCAN_GetDefaultConfig(&flexcanConfig);
#if defined(CAN_CTRL1_CLKSRC_MASK)
if (!FSL_FEATURE_FLEXCAN_INSTANCE_SUPPORT_ENGINE_CLK_SEL_REMOVEn(EXAMPLE_CAN))
{
flexcanConfig.clksrc=kFLEXCAN_ClkSrcPeri;
}
#endif
flexcanConfig.enableLoopBack = true;
FLEXCAN_Init(EXAMPLE_CAN, &flexcanConfig, EXAMPLE_CAN_CLK_FREQ);
/* Setup Rx Message Buffer. */
mbConfig.format = kFLEXCAN_FrameFormatStandard;
mbConfig.type = kFLEXCAN_FrameTypeData;
mbConfig.id = FLEXCAN_ID_STD(0x123);
FLEXCAN_SetRxMbConfig(EXAMPLE_CAN, RX_MESSAGE_BUFFER_NUM, &mbConfig, true);
FLEXCAN_SetTxMbConfig(EXAMPLE_CAN, TX_MESSAGE_BUFFER_NUM, true);
/* Create FlexCAN handle structure and set call back function. */
FLEXCAN_TransferCreateHandle(EXAMPLE_CAN, &flexcanHandle, flexcan_callback1, NULL);
}初始化为Loopback模式，CAN ID为0x123，回调函数为flexcan_callback1:
static EventGroupHandle_t txEvent;
static void flexcan_callback1(CAN_Type *base, flexcan_handle_t *handle, status_t status, uint32_t result, void *userData)
{
BaseType_t xHigherPriorityTaskWoken, xResult;
switch (status)
{
/* Process FlexCAN Rx event. */
case kStatus_FLEXCAN_RxIdle:
if (RX_MESSAGE_BUFFER_NUM == result)
{
rxComplete = true;
}
break;
/* Process FlexCAN Tx event. */
case kStatus_FLEXCAN_TxIdle:
if (TX_MESSAGE_BUFFER_NUM == result)
{
txComplete = true;
xEventGroupSetBitsFromISR(txEvent, 0x01, &xHigherPriorityTaskWoken);
}
break;
default:
break;
}
}
3、收发调试函数
每次发送后，等待callback函数中的txEvent事件进行同步
static void flexCanTest(void)
{
PRINTF("\r\n==FlexCAN loopback example -- Start.==\r\n\r\n");
/* Prepare Tx Frame for sending. */
txFrame.format = kFLEXCAN_FrameFormatStandard;
txFrame.type = kFLEXCAN_FrameTypeData;
txFrame.id = FLEXCAN_ID_STD(0x123);
txFrame.length = 8;
txFrame.dataWord0 = CAN_WORD0_DATA_BYTE_0(0x11) | CAN_WORD0_DATA_BYTE_1(0x22) | CAN_WORD0_DATA_BYTE_2(0x33) |
CAN_WORD0_DATA_BYTE_3(0x44);
txFrame.dataWord1 = CAN_WORD1_DATA_BYTE_4(0x55) | CAN_WORD1_DATA_BYTE_5(0x66) | CAN_WORD1_DATA_BYTE_6(0x77) |
CAN_WORD1_DATA_BYTE_7(0x88);
PRINTF("Send message from MB%d to MB%d\r\n", TX_MESSAGE_BUFFER_NUM, RX_MESSAGE_BUFFER_NUM);
PRINTF("tx word0 = 0x%x\r\n", txFrame.dataWord0);
PRINTF("tx word1 = 0x%x\r\n", txFrame.dataWord1);
rxXfer.mbIdx = RX_MESSAGE_BUFFER_NUM;
rxXfer.frame = &rxFrame;
FLEXCAN_TransferReceiveNonBlocking(EXAMPLE_CAN, &flexcanHandle, &rxXfer);
/* Send data through Tx Message Buffer. */
txXfer.mbIdx = TX_MESSAGE_BUFFER_NUM;
txXfer.frame = &txFrame;
FLEXCAN_TransferSendNonBlocking(EXAMPLE_CAN, &flexcanHandle, &txXfer);
rxComplete = false;
txComplete = false;
/* Waiting for Rx Message finish. */
xEventGroupWaitBits(txEvent, 0x01, pdTRUE, pdFALSE, portMAX_DELAY);
// while ((!rxComplete) || (!txComplete))
// {
// vTaskDelay(10);
// };
PRINTF("\r\nReceived message from MB%d\r\n", RX_MESSAGE_BUFFER_NUM);
PRINTF("rx word0 = 0x%x\r\n", rxFrame.dataWord0);
PRINTF("rx word1 = 0x%x\r\n", rxFrame.dataWord1);
PRINTF("\r\n==FlexCAN loopback example -- Finish.==\r\n");
}4、建立Freertos任务，每500ms发送一次数据
void flexCanTestTask(void *ptr)
{
flexCanTestInit();
txEvent = xEventGroupCreate();
while(1)
{
flexCanTest();
vTaskDelay(500);
}
}
现在的现像是发了一阵之后就卡死在了如下的事件等待中。
xEventGroupWaitBits(txEvent, 0x01, pdTRUE, pdFALSE, portMAX_DELAY);
5、除了测试了任务，另外建立了几个任务如下：
UART1 driver task 是我自己写的uart驱动
IDLE是自己定义的IDLE任务
FlexCan Test Task 就是上述的测试任务
我的环境为：SDK使用的是2.4.1，MCUXpresso为10.3.1
