I am sending data over CAN to a unit using ncWrite
and I am sending a block of 250 byes, [to send about 1.3 meg total, in 250 byte block increments.]
2 bytes header and 6 bytes of data (41 times) = 246 bytes
then one more with 2 byte header and 4 bytes of data
the last one is the only message that has a response.
In one set up, that works in my code ALL the time.
the same exact version, both set ups using the NI PCI CAN device, with the save drivers versions, the same version of the Runtime engine,
but the second set up fails once in a while (last set of runs is was 13% of the time).
The only time I can determine if a failure has occures, is with the response to the last message (with the last 4 bytes).
The error is BFF62001 - basically no reponse.
So, my guess is that the module I am sending data to missed one or more messages, and is expecting more data, so it is not responding, because it has not received the full 250 bytes.
Is there any way I can determine anything to identify an error or missed message from the ncWrite.
I don't know if this would help, but here is the write command:
error = ncWrite(handle, sizeof(*CanFrame), CanFrame);
And, I read as much as I could find in the forums, and help, and added a wait:
error = ncWaitForState(handle, NC_ST_WRITE_SUCCESS, 250, &state);
but this does not seem to help.
I thought it would insure a wait after the write to insure the write was accepted or in some sort of positive state that would be better than not having the wait.
With and without the wait work on the fisrt set up.
Both work about the same on the second set up, right now about 13% failure.
Oh, and when I run it a second time, the failed unit almost always passes.
Any ideas?
