FlexCAN初始化注意事项

yt0069

SDK中FlexCAN初始化注意事项：
如果采用中断方式收发，注册回调函数FLEXCAN_DRV_InstallEventCallback和FLEXCAN_DRV_InstallErrorCallback，以及mailbox或fifo，滤波器的初始化需要放在启动接收函数之前

例如，以下为不太合理的邮箱初始化程序：

/* Config rx messages mailbox */
        for (index = 0; index < Appl_Can_NodeRxMsgCount[canNodeIndex]; index++)
        {
            /* Config rx buffer */
            status = CAN_ConfigRxBuff(&can_pal_instance,
                                      index,
                                      &Appl_Can_StdIdBuffCfg,
                                      (uint32_t)Appl_Can_NodeRxMsgPtr[canNodeIndex][index].id);
            /* start to receive message */
            status = CAN_Receive(&can_pal_instance,
                                 index,
                                 (can_message_t *)&Appl_Can_NodeRxMsgPtr[canNodeIndex][index]);
        }

应更改为：

/* Config rx messages mailbox */
        for (index = 0; index < Appl_Can_NodeRxMsgCount[canNodeIndex]; index++)
        {
            /* Config rx buffer */
            status = CAN_ConfigRxBuff(&can_pal_instance,
                                      index,
                                      &Appl_Can_StdIdBuffCfg,
                                      (uint32_t)Appl_Can_NodeRxMsgPtr[canNodeIndex][index].id);
        }
        for (index = 0; index < Appl_Can_NodeRxMsgCount[canNodeIndex]; index++)
        {
             /* start to receive message */
            status = CAN_Receive(&can_pal_instance,
                                 index,
                                 (can_message_t *)&Appl_Can_NodeRxMsgPtr[canNodeIndex][index]);
        }

run

配置顺序:

先配置所有需要配置的邮箱的独立掩码（如果需要）:
FLEXCAN_DRV_SetRxMaskType(instance, FLEXCAN_RX_MASK_INDIVIDUAL);
FLEXCAN_DRV_SetRxIndividualMask();
再配置所有需要配置的邮箱Mailbox
FLEXCAN_DRV_ConfigRxMb();
安装中断回调函数
FLEXCAN_DRV_InstallEventCallback();
FLEXCAN_DRV_InstallErrorCallback();
最后启动接收(使能邮箱中断）
FLEXCAN_DRV_Receive();

示例：

/* Set the individual mask type */
FLEXCAN_DRV_SetRxMaskType(CAN_INST, FLEXCAN_RX_MASK_INDIVIDUAL);

/* Set standard individual mask, bit 0-11 Optional, this example STD_ID 0x700U - 0x7FFU will be receive */
FLEXCAN_DRV_SetRxIndividualMask(CAN_INST, FLEXCAN_MSG_ID_STD, RX_STD_MAILBOX, 0xF00U);
/* Set extended individual mask, bit 0-28 Optional, this example EXD_ID 0x18C00100U - 0x18C001FFU will be receive */
FLEXCAN_DRV_SetRxIndividualMask(CAN_INST, FLEXCAN_MSG_ID_EXT, RX_EXT_MAILBOX, 0x1FFFFF00U);

/* After configure all individual masks, then congigure rx mailbox */
status |= FLEXCAN_DRV_ConfigRxMb(CAN_INST, RX_STD_MAILBOX, &rxMbStdInfo, RX_STD_MSG_ID);
status |= FLEXCAN_DRV_ConfigRxMb(CAN_INST, RX_EXT_MAILBOX, &rxMbExtInfo, RX_EXTMSG_ID);

/* Install rx callback */
FLEXCAN_DRV_InstallEventCallback(CAN_INST, DRV_CAN_RxEventCall, NULL);
FLEXCAN_DRV_InstallErrorCallback(CAN_INST, DRV_CAN_ErrorCall, NULL);

/* Start receiving data in RX_STD/EXT_MAILBOX. */
status |= FLEXCAN_DRV_Receive(CAN_INST, RX_STD_MAILBOX, &rxStdMsg);
status |= FLEXCAN_DRV_Receive(CAN_INST, RX_EXT_MAILBOX, &rxExtMsg);

qinhongkui

楼主有CAN中断接收的demo吗？

YQH

此主題已被删除！

qinhongkui

YQH 非常谢谢

Ekko

yt0069 如果注册回调函数放在接收函数之后，可能会出现什么情况，目前有客户这样做，会偶发出现固定接收不到某一个ID，我帮他修改初始化流程之后，目前还没复现，想确认一下原理。

YQH

Ekko 客户是什么用法，是在总线已有其他节点发报文的情况下再接入自己的控制器时出现某个报文接收不到的情况吗

Ekko

YQH 目前测试情况是通过CANOE一直在发报文，MCU重复上电，偶发出现

YQH

qinhongkui
CAN_INT_Demo.zip

run

配置顺序:

先配置所有需要配置的邮箱的独立掩码（如果需要）:
FLEXCAN_DRV_SetRxMaskType(instance, FLEXCAN_RX_MASK_INDIVIDUAL);
FLEXCAN_DRV_SetRxIndividualMask();
再配置所有需要配置的邮箱Mailbox
FLEXCAN_DRV_ConfigRxMb();
安装中断回调函数
FLEXCAN_DRV_InstallEventCallback();
FLEXCAN_DRV_InstallErrorCallback();
最后启动接收(使能邮箱中断）
FLEXCAN_DRV_Receive();

示例：

/* Set the individual mask type */
FLEXCAN_DRV_SetRxMaskType(CAN_INST, FLEXCAN_RX_MASK_INDIVIDUAL);

/* Set standard individual mask, bit 0-11 Optional, this example STD_ID 0x700U - 0x7FFU will be receive */
FLEXCAN_DRV_SetRxIndividualMask(CAN_INST, FLEXCAN_MSG_ID_STD, RX_STD_MAILBOX, 0xF00U);
/* Set extended individual mask, bit 0-28 Optional, this example EXD_ID 0x18C00100U - 0x18C001FFU will be receive */
FLEXCAN_DRV_SetRxIndividualMask(CAN_INST, FLEXCAN_MSG_ID_EXT, RX_EXT_MAILBOX, 0x1FFFFF00U);

/* After configure all individual masks, then congigure rx mailbox */
status |= FLEXCAN_DRV_ConfigRxMb(CAN_INST, RX_STD_MAILBOX, &rxMbStdInfo, RX_STD_MSG_ID);
status |= FLEXCAN_DRV_ConfigRxMb(CAN_INST, RX_EXT_MAILBOX, &rxMbExtInfo, RX_EXTMSG_ID);

/* Install rx callback */
FLEXCAN_DRV_InstallEventCallback(CAN_INST, DRV_CAN_RxEventCall, NULL);
FLEXCAN_DRV_InstallErrorCallback(CAN_INST, DRV_CAN_ErrorCall, NULL);

/* Start receiving data in RX_STD/EXT_MAILBOX. */
status |= FLEXCAN_DRV_Receive(CAN_INST, RX_STD_MAILBOX, &rxStdMsg);
status |= FLEXCAN_DRV_Receive(CAN_INST, RX_EXT_MAILBOX, &rxExtMsg);

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FlexCAN初始化注意事项

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