Modpoll - Polling slave (Ctrl-C to stop) ...Reply time-out!


Thread Starter

John Carvajal


I'm working on a communications project with RS232 converter to ethernet. The serial is 174 CEV 300 10, the communication is through serial port and ethernet. I have already all configured, but when I executed this command: "modpoll -m enc -t 4:float" this message appears:

Polling slave (Ctrl-C to stop) ...
Reply time-out!

And I can't get data.
Which ways are you trying to poll? From an ethernet driver through the gateway to a serial device or from a serial device through the gateway to an ethernet device?

Make sure your Unit numbers are correct for the devices attached - you can actually have an RS485 drop of several serial devices connected to the gateway. Use the '-a x' option where x is your unit number with Modpoll.

Hope this helps.
i am also having same problem

win\modpoll -b 9600 -p even -m rtu -a 1 -t4:float -r 100 -c 10 COM8
modpoll 3.6 - FieldTalk(tm) Modbus(R) Master Simulator
Copyright (c) 2002-2018 proconX Pty Ltd
Visit for Modbus libraries and tools.

Protocol configuration: Modbus RTU
Slave configuration...: address = 1, start reference = 100, count = 10
Communication.........: COM8, 9600, 8, 1, even, t/o 1.00 s, poll rate 1000 ms
Data type.............: 32-bit float, output (holding) register table

-- Polling slave... (Ctrl-C to stop)
Reply time-out!
-- Polling slave... (Ctrl-C to stop)
Reply time-out!
-- Polling slave... (Ctrl-C to stop)
Reply time-out!