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Array APB PLC's
#1
Hello,

I am trying to connect with this PLC but it has only Modbus RTU Extended. How can I connect with such solution?
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#2
It depends on what is meant by "Extended" protocol. If this means that the whole 65536 address range can be used for coils and registers then it's already supported. If this means some non-standard things like 2-byte device addressing then it's not supported.
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#3
I know that other device(LM) should support multiregister function(ability to writing values to 2 address). But now I want only check connection and I have nothing.

Connection parameters should be:
Baudrate: 9600,
Data bits: 8,
Stop bits: 1,
Parity: None

I have on LM these parameters:
RTU-serial enabled: yes
Port: /dev/RS485-1,
Baudrate: 9600,
Parity: None(1 stop bit)
Half-duplex

I know that device has address 2.
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#4
There are some devices which do not answer to read/write requests to an invalid coil/register address, where they should give an error response according to standard behavior. Maybe this is the case. Have you tried using RTU read test?
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#5
Yes, I've tried and in this interface PLC give an answer and answer is correct.

Now I am trying to prepare profile.

How it should look for this data(checked in Modbus RTU read):
Function: Coil
Address: 512
Read swap: Word(CDAB)
Read length: 1
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#6
Code:
{ "name": "Coil 512", "bus_datatype": "bool", "type": "coil", "address": 512, "writable": true }
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