Sten Siren

Listen-only CAN on 908AZxxA

Discussion created by Sten Siren on Nov 24, 2006
Latest reply on May 12, 2009 by Daniel Lundin
I would need to make an automatic bitrate detection for a set of old hardwares built around the HC908AZ32A and HC908AZ60A controllers. I have already successfully done it on the newer, S12D-based hardwares, but it uses the MSCAN's Listen-Only Mode, and that mode does not exist in the older MSCAN08 on the 908AZ-controllers.
 
On the S12D I have done it so that when the system starts, it puts the CAN-interface in Listen-Only Mode and then scans though the different bitrates until a legal frame is received, after which the bitrate is locked and the Listen-Only Mode is cleared. I think that the Listen-Only Mode is needed so that a node, that is currently scanning on a faulty bitrate, does not mark frames on the bus as errorframes.
 
Do anybody have a solution how to do it on a HC908AZ without changing the hardware?

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