Author Topic: How to set the port number to 502?  (Read 2326 times)


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How to set the port number to 502?
« on: March 29, 2020, 10:43:33 pm »
Hi mate,

I really like the intention behind this app, but it does not allow me to enter a port number lower than 1000.  Most plcs cant change the modbus tcp Port number.

Can you release an update that allows this?

I even tried to modify the plist file but this has been sewn up tightly too. Almost as if it were intentional.



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Re: How to set the port number to 502?
« Reply #1 on: April 24, 2021, 09:20:08 am »
Prior to macOS V10.14 (Mojave) all ports below 1023 require root privileges for full access. A workaround solution is explained in the ModbusClient Help section.
From 10.14 onwards this restriction has been removed and you can simply set the port number to 502.