When we updated from IQAN4 to 5, it seems a couple of things didn't work anymore regarding precise timing of when (J1939) CAN messages our sent.
Problem #1: Sending 2 messages at the same time.
We had 2 messages that should be sent at the exact same time. We simply had the send-method fixed on 250 milliseconds or something. But since IQAN5, the receiver wouldn't get both messages at the same time.
Now we fixed that by using a Trigger instead (using an IDC that pulses every x millisec). But is this a bug, or intended behavior? Maybe CAN frames have random send-offsets to spread them over time, reducing peak-loads?
Problem #2: CRC checksum + Counting
It becomes more problematic on another machine. The receiver (ZF transmission) requires the messages we send to have a CRC checksum byte, and a message-counter byte. Back then, IQAN didn't have the Checksum channels yet, so we made it by hand.
Works in IQAN4, didn't work anymore in IQAN5 (ZF says the messageCounter is wrong). I guess it has something to do with the order of counting and actually sending. Again, could there be some offset that wasn't there before?
As for using the IQAN(5) CRC component, we didn't had success yet. Either our specific method isn't supported, or it suffers from the same counting issue. In this case we need
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