[Interest] QModbusTcpClient - More than one Modbus ID query in TCP Package

[Alexander Blasche]

________________________________________
From: Interest <interest-bounces+alexander.blasche=qt.io at qt-project.org> on behalf of Pfeiffer, Stephan <Stephan.Pfeiffer at binder-world.com>
Sent: Wednesday, 21 December 2016 11:18
To: 'Interest at qt-project.org'
Subject: Re: [Interest] QModbusTcpClient - More than one Modbus ID query in TCP Package

>Your first hint was worth one's weight in gold. I've found my mistake with the detailed logging.

Glad I could help.

>The problem wasn't the amount of Modbus packages within one TCP package. It seems like that in Wireshark.
>But the problem was the timeout value which was preset to low.

Looped writes to multiple targets are not really permitted in the Modbus spec. It uses a request-response pattern. You have to wait for the response or the timeout before the next response can be sent.

--
Alex