你好！
我在调试通过TMS570 DCAN接收毫米波雷达ARS408的数据的时候遇到问题，怎么也收不到数据。
我是通过将示例程序里的example_canCommunication.c修改一下来进行调试的，就是不再向CAN1发送数据，直接从CAN2接收数据，CAN2接到毫米波雷达的CAN口。
现在只知道毫米波雷达的位速率是500k bits/s，这个例子本身也是配的500k bits/s。can.c中关于canReg2部分的设置代码如下：
/** @b Initialize @b CAN2: */
/** - Setup control register
* - Disable automatic wakeup on bus activity
* - Local power down mode disabled
* - Disable DMA request lines
* - Enable global Interrupt Line 0 and 1
* - Disable debug mode
* - Release from software reset
* - Enable/Disable parity or ECC
* - Enable/Disable auto bus on timer
* - Setup message completion before entering debug state
* - Setup normal operation mode
* - Request write access to the configuration registers
* - Setup automatic retransmission of messages
* - Disable error interrupts
* - Disable status interrupts
* - Enter initialization mode
*/
canREG2->CTL = (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)((uint32)0x00000005U << 10U)
| 0x00020043U;
/** - Clear all pending error flags and reset current status */
canREG2->ES |= 0xFFFFFFFFU;
/** - Assign interrupt level for messages */
canREG2->INTMUXx[0U] = (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U;
canREG2->INTMUXx[1U] = (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U
| (uint32)0x00000000U;
/** - Setup auto bus on timer period */
canREG2->ABOTR = (uint32)0U;
/** - Initialize message 1
* - Wait until IF1 is ready for use
* - Set message mask
* - Set message control word
* - Set message arbitration
* - Set IF1 control byte
* - Set IF1 message number
*/
/*SAFETYMCUSW 28 D MR:NA <APPROVED> "Potentially infinite loop found - Hardware Status check for execution sequence" */
while ((canREG2->IF1STAT & 0x80U) ==0x80U)
{
} /* Wait */
//canREG2->IF1MSK = 0xC0000000U | (uint32)((uint32)((uint32)0x000007FFU & (uint32)0x1FFFFFFFU) << (uint32)0U);
canREG2->IF1MSK = 0x00000000U;
//canREG2->IF1ARB = (uint32)0x80000000U | (uint32)0x40000000U | (uint32)0x00000000U | (uint32)((uint32)((uint32)1U & (uint32)0x1FFFFFFFU) << (uint32)0U);
canREG2->IF1ARB = (uint32)0x80000000U | (uint32)0x40000000U | (uint32)0x00000000U;
//canREG2->IF1MCTL = 0x00001080U | (uint32)0x00000000U | (uint32)0x00000000U | (uint32)8U;
canREG2->IF1MCTL = 0x00000080U | (uint32)0x00000000U | (uint32)0x00000000U | (uint32)8U;
canREG2->IF1CMD = (uint8) 0xF8U;
canREG2->IF1NO = 1U;
/** - Setup IF1 for data transmission
* - Wait until IF1 is ready for use
* - Set IF1 control byte
*/
/*SAFETYMCUSW 28 D MR:NA <APPROVED> "Potentially infinite loop found - Hardware Status check for execution sequence" */
while ((canREG2->IF1STAT & 0x80U) ==0x80U)
{
} /* Wait */
canREG2->IF1CMD = 0x87U;
/** - Setup IF2 for reading data
* - Wait until IF1 is ready for use
* - Set IF1 control byte
*/
/*SAFETYMCUSW 28 D MR:NA <APPROVED> "Potentially infinite loop found - Hardware Status check for execution sequence" */
while ((canREG2->IF2STAT & 0x80U) ==0x80U)
{
} /* Wait */
canREG2->IF2CMD = 0x17U;
/** - Setup bit timing
* - Setup baud rate prescaler extension
* - Setup TSeg2
* - Setup TSeg1
* - Setup sample jump width
* - Setup baud rate prescaler
*/
canREG2->BTR = (uint32)((uint32)0U << 16U) |
(uint32)((uint32)(3U - 1U) << 12U) |
(uint32)((uint32)((5U + 3U) - 1U) << 8U) |
(uint32)((uint32)(3U - 1U) << 6U) |
(uint32)14U;
/** - CAN2 Port output values */
canREG2->TIOC = (uint32)((uint32)1U << 18U )
| (uint32)((uint32)0U << 17U )
| (uint32)((uint32)0U << 16U )
| (uint32)((uint32)1U << 3U )
| (uint32)((uint32)1U << 2U )
| (uint32)((uint32)1U << 1U );
canREG2->RIOC = (uint32)((uint32)1U << 18U )
| (uint32)((uint32)0U << 17U )
| (uint32)((uint32)0U << 16U )
| (uint32)((uint32)1U << 3U )
| (uint32)((uint32)0U << 2U )
| (uint32)((uint32)0U <<1U );
/** - Leave configuration and initialization mode */
canREG2->CTL &= ~(uint32)(0x00000041U);
我的问题是 canREG2->IF1ARB 中的 Xtd 和 ID[28：0] 貌似很重要，因为我从DCAN1发送数据到DCAN2，如果更改了接收方的 Xtd 和 Message Identifier，会接收不到数据，Xtd应该是表示帧格式是 Standard Frame or Extended Frame， 那 Message Identifier 怎么理解昵？
另外，只知道毫米波雷达的位速率为500k的情况下能正确接收到数据吗？（不知道 Xtd 和 Message Identifier），还有我想不用 acceptance filtering，我的代码里的改动正确吗？ （将canREG2->IF1MSK 设为全0， 将 canREG2->IF1MCTL 中的 UMask 设为0）
