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Auto answer transmit CAN messages with NTCAN

refer to NTCAN Application Developers Manual document charpter

3.12 Object Mode (Transmit), Autoanswer Mode
4.2.9 canIoctl(), Tx-Object Mode related I/O controls

example code

autoanswer.c：程序展示如何配置Auto Answer Mode。执行过程中使用canRead()方式循环读取CAN消息，并且根据CAN消息的ID的不同，做出如下响应。

如果收到CAN消息ID为0，则退出程序。
如果收到CAN消息ID为1，则开启自动应答功能。
如果收到CAN消息ID为2，则关闭自动应答功能。
如果收到CAN消息ID为3，并且为RTR消息，则自动应答一条CAN消息，ID同样为3，Data为1 byte记录了程序接收到CAN消息的数目。

执行过程

可以使用CANreal工具发送ID为3的RTR消息，参见下面图一。

Send CAN msg with 11-bit ID to: 
ID=0:       Exit program
ID=1:       Switch ON auto answer
ID=2:       Switch OFF auto answer
ID=3 + RTR: Get auto answered CAN msg recording
            the total number of received CAN msgs. 

canRead() returned timeout
canRead() returned timeout
Id of received message :4!
Id of received message :5!
Id of received message :6!
Id of received message :7!
Id of received message :8!
Id of received message :9!
Id of received message :a!
canRead() returned timeout
canRead() returned timeout
Id of received message :2!
Auto answer switched OFF!
Id of received message :1!
Auto answer switched ON!
Id of received message :0!
Exit program!

截图

图一