Receiving Freeform CAN messages that are 15 bits long( over 2 bytes)
Hi,
we are doing a new config for a new customer who wants to display all 4 wheels speeds on a PV780.
The graphics are done, the variables all defined and the signal structure all defined as per the OEM CAN 2.0A specification.
When I perform a validation, Powervision gives me 4 errors for the 4 signals that spread over 2 bytes of data, but do not completely fill the bytes. There is a direction indicator bit that fills the last bit as a separate signal.
Surely this is possible, or is this a bug?
Is there a way around this via scripting or some other method we could use meanwhile?
A couple of screen grabs below showing the data(names removed to protect the client confidential data):
Using Powervision 2.9.21075.
Errors( for the 4 x 15 bit long wheel speeds), OEM spec, Powervision view.
Many thanks, Dave.
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Ive raised this as a feature request.
Meanwhile, the way we worked around this, as it was solved by Nan @ Murphy in the UK, not us, so it's worthwhile benefit showing the community as I'm sure other will have had a similar issue.
we modify the spec of the 15 bit signal to 16 bits ( 2 full bytes, changing the start bit from 1 to 0)
Then perform a calc that fires on change as follows:
the 1 at the end denotes the bits it needs shifting.
the 32767 is calculated as: 2 raised to the power of 15, minus 1. Where 2 is base 2, 15 is the number of bits and 1 being the value of 2 raised to power 0.
this then gives us the same value with the calulated vlaue as we see in CANCapture using the DBC file :)
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