Modbus TCP error code -7006 between CI867 and Unitrol AVR
I have a problem with Modbus TCP communication between an Unitrol AVR and a CI867 card. The connection to the Unitrol itself is ok (MBTCPConnect block receives valid signal back), but when I try to read some holding registers (%QW10#100), the MBTCPRead block shows the error code -7006.
In order to troubleshoot the problem, I've tried to read the values from the Unitrol with a Modbus master installed on my PC (ModScan). From this tool I can read the values without errors. Furthermore I have simulated the Unitrol, by attaching my computer with a Modbus slave (ModSim) installed. The CI867 was able to see the values from this slave without any errors.
In order to give you some more information, I've attached a pdf file with screendumps.
The Modbus slave device ID is 64.
I'm trying to read holding register 40101 and 40102
IP-address for Unitrol is 172.16.80.105
If more information is needed, please don't hesitate to write it, and thank you very much for your answers in advance.