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Omron MODBus

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I'm attempting to connect a CJ1W-SCU32 modbus card with 2 ports to several modbus sensors. I am only reading from the senors, not sending any commands. I have been told two different ways to do this: 1. CMND block using Modbus RTU code 2804. 2. Using the Protocol Macro ModbusPM_Master with the PMCR function block. I've additionally found an easy modbus configuration tool that unfortunately seems to take up too many registers that I will be using. Does anyone have any examples of code for setting up MODBUS TCP with either of those 2 methods? I am having a hard time finding any. Thanks.

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MODBUS TCP?? Uses Ethernet connections. We can help you here but we will need to know if you are using sensors with MODBUS RTU which uses serial connections? or MODBUS TCP which uses Ethernet connections?

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Okay, here is the story: I have several MODBus RTU Devices that are talking over serial on a SCU32. I have downloaded and installed the Modbus v5.1 protocol macro from this site. I am using the example program configured for my CJ2H PLC. My modbus device,a HACH SC200, used to read conductivity, is wired up to the PLC using RS485 half duplex 2/wire. I have setup, following the modbus documentation, the following commands: Control word 1: 0112 (Logical port 0, serial port 1, unit of scu32:2 (+10) = 12 Word D29609: 0004 hex (4 words) Word D29610: 0004 (Slave #4) Word D29611: 9C44 (Modbus register 40004, floating point 2 words) Word D29612: 0002 (2 words) For the longest time, I was getting an error light on the SCU32 unit. I was using 7E2 and I changed it to 8N1 for my communications settings and that seemed to correct itself and now I see send and receive lights. However, I still don't get any values and I am expecting to get a temperature of 24.7 deg C. Does this look like I've set it up correctly? thank you

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Good afternoon ,

My system was working in modbus rtu in a port 1 of a scu32, i need to change it to port 2 because i have a phisical problem with the port 1. My question is , how can i do it? i tried to change the number of port in the PMCR in C1: (WAS #111, I changed it to #121 but it don´t worked

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Change it to #211.

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Thank you Jay Anthony, it worked !

I am new in programming , so this forum will help me a lot,

Sorry my english.

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