LLCE CAN

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LLCE CAN

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JACK_Q
Contributor I

在进行LLCE CAN通信时,发现一个问题,当环境是两个can节点直连配有两个终端电阻120欧姆,对端设备处于监听模式时会触发ACKERR,同时LLCE固件会自动重传,这个重传的好像是以总线的最大带宽在发送,想问下是否有什么方式可以配置自动重传的次数或者怎么停止自动重传

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JACK_Q
Contributor I
使用的是RTDSW32G_RTD_4.4_4.0.2_P04_D2312,S32G_LLCE_1_0_9
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chenyin_h
NXP Employee
NXP Employee

Hello, @JACK_Q 

您好

从我的理解来看,应该和LLCE软件无关,这主要是CAN协议层ACK机制导致的,对端处于 listen-only模式时不发送 ACK,此时S32G LLCE侧发出的帧得不到ACK,就会报 ACKERR,随后控制器继续重传,这符合CAN发送失败后的行为。

以上操作是协议规定的,我没看到有配置可以设置重传次数

 

BR

Chenyin

 

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JACK_Q
Contributor I
在项目的实际应用上肯定是不希望因为ACKERR或者其他问题导致的重传而出现网络风暴的,所以我想知道能不能关闭自动重传。如果没有对于控制自动重传的选项,是不是就只能软件监控了配置对于策略了
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chenyin_h
NXP Employee
NXP Employee

Hello, @JACK_Q 

我理解您的情况,确实一般可以考虑在上层软件监控并配置对应的处理策略。

 

BR

Chenyin

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