AnsweredAssumed Answered

vrf VEE stopping at 0x0a ("LF") update

Question asked by flo on Aug 24, 2007
Latest reply on Aug 24, 2007 by VRFuser

I was able to do some more testing which showed that changing/deleting the read terminator (default: "
")in instrument manager sadly did not help at all.

This thing is weird,
as written I receive 70 bytes (wich are valid and sent correctly),

Most of the time (sometimes it works as it should) Vee stops with 0x0A (LF) (0x0A is always the 60th byte of the 70) being the last byte received.
Then I get error 701 "End of file or no data found"
(this points to something really interpreting 0x0A as the read terminator), next time I read data I get the missing 10 bytes.

Additionally I checked if there was a read terminator set in the configurations options for the serial multiport card we use (Meilhaus 9000 ... a3833f4bd7).
This was not the case.

More and more I believe that there's timing/interrupt problem with the control unit, however I can not believe that the problem appears always with the same byte then.
Furthermore we have a linux based service programm (no source code
unfortunately) which reads and writes the same data with the same hardware flawlessly.

An further suggestions?


Original post/problem:


having a little problem here:

VEE 7.0
serial connection
task: read a set of 70 bytes
from 4 control units

I try to read 70 Bytes,
but whenever I read a certain 0x0a VEE stops reading data

what did I try:
checked cable connection, ok
checked general communication, ok
(ack and nack's are sent correctly)
checked voltage levels with oszi, ok
the vee programm is the same for the 4 units, increased timeout, no change

Any ideas why this happens?

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