MCF5235 FlexCAN transmits continuously

[JulienP]

Hello,

I'm running into a very strange problem with the FlexCAN. Quick example:

- I'm trying to transmit 0x18DAEEFB | 02-10-7E-FF-FF-FF-FF-BB. It is sent once, no errstat or errcnt, it works fine.

- I'm trying to transmit 0x18DAEEFB | 02-10-7E-FF-FF-FF-FF-CC. FlexCAN is transmitting continuously, errcnt is inscreasing, BIT1ERR, BUSOFF and others bit error are set (BUSOFF interrupt is disabled). The Control/Status register of the MB remains activate. The only way to stop this mess is to set the MB to inactive state by myself. Of course, the frame is sent to the same target, and there are no differences between those two frames for the target. In addition, the target is answering many times as well.

- All the frames are transmitted well (once) using LoopBack mode.

This is just one example, but it is doing the same with many frames. My functions are in attachment.

Do I do something wrong?

[Britti1982]

I'm new in the world MQX
 I work with MCF5225evb recently and I am trying the sample project for use on the FlexCAN demoboard.
 making debugging and looking CANL and CANH bus oscilloscope I see that the frames are continuous, even if I start with debugging in the STOP condition.
 Why does this happen?
 and then because the serial transmission is complete even if there are other nodes send their ACKs connected on the bus?

help me please.

[JulienP · Accepted solution]

I solved it using EXTAL clock instead of PLL clock!

Bye!

Julien.