Hello,
we found some difference between application running in PC and runing in TPC2012 device.
We tested modbus communication via RS485 (9600b/s, 8bits, parity even) between PLC(master) and TPC2012 (slave). We used Visa read object and set parity to Even via property node. From the PLC we sent request to device and in our application we only read the data from PLC and displayed it (8bytes) on sreen.
If we tested the application on PC everything worked fine. But if we compiled application and ran it in TPC2012 device the data was different (for example if I sent request from PLC to slave 05 03 00 01 00 01 crc crc on the TCP I saw 00 03 00 01 00 01 crc crc. The crc on TPC wasn't equal to crc on PLC.
We found that problem was in VISA read setiing for read data in TPC device. If we set parity to SPACE (instead of EVEN) then we read data correctly.
Modbus - Parity set for VISA read object:
Master PLC (even) - PC (even) -> visa read - data are equal
Master PLC (even) - TPC (even) -> visa read - data aren't equal
Master PLC (even) - TPC (space)-> visa read - data are equal
PC: Win XP SP2, LabView 8.5 with LabView TP module 8.5.
TPC2012: WinCE 5.0, NI visa 4.2, NI TPC Service 1.0.
Best regards,
Pavel Rucka.
