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Click PLC RS485 (Port3) ASCII Protocol Issue

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  • Mvlawn
    started a topic Click PLC RS485 (Port3) ASCII Protocol Issue

    Click PLC RS485 (Port3) ASCII Protocol Issue

    I'm trying to communicate with an Opto 22 LED Dimmer. The Opto 22 uses 485/ASCII or 485/Optomux protocol. We are using ASCII. I set the Opto 22 up using the dip switches per the manual and have matched those settings in our Click PLC port 3 COM setup. I tested communication outside of the Click PLC using the MODSCAN utility and it is talking just fine. I can issue commands to the Opto 22 and have it respond correctly. I set up a SEND block in the Click program but cannot get the Opto22 to respond at all. I'm unfamiliar with the Click programming and am not sure if the program is adding the lead in bit of ':' or the LRC at the end of the string. If I'm trying to write to slave 2, register 1 (holding register) and send a value of 5000, what do I need to input into the static text box on the Click program SEND block??

    Any direction on this would be greatly appreciated.

  • kewakl
    replied
    Originally posted by Do_more PE
    Click will not talk MODBUS ASCII it only talks MODBUS RTU.
    As bernie alluded to:
    Originally posted by bcarlton
    For the particular unit you might wish to use the OPTOMUX protocol
    You may be able to build an OPTOMUX-compliant string to send to the Opto22 module(s).
    You may even be able to parse the response(s).

    We don't have your setup hardware, so we cannot test/build anything for you.
    All we can do is make guesswork that may or may not be of use to you.
    If you do follow any of our advice, remember:
    -there is no guarantee that anything we say will work.
    -there is no guarantee that anything we say WILL NOT cause you grief and hardship.
    -there is no guarantee that we can respond in a timely manner.

    I guess that I have a irrational urge to attempt to make things talk.

    Originally posted by kewakl
    Issue what commands?
    -and-
    What did you put in the SEND block?
    Originally posted by Mvlawn
    In the "MODSCAN64" Scanner, I sent various levels of brightness values and ramp vs bright levels. Values ranged from 1000-35000 in accordance with the Opto 22 manual. The registers that showed up on the holding register scan using "MODSCAN64" were 400001 (duty cycle), 400017 (brightness), 400049 (ramp/brightness). Registers 400001-400016 are read/write, anything above 400016 are write only.
    What was the actual TEXT of what you entered in ModScan64 and what was the actual TEXT of what you entered in the Send dialog in CLICK?

    Do you have access to any serial protocol analyzer? I am partial to Saleae Logic

    Leave a comment:


  • Mvlawn
    replied
    Hi kewakl.

    In the "MODSCAN64" Scanner, I sent various levels of brightness values and ramp vs bright levels. Values ranged from 1000-35000 in accordance with the Opto 22 manual. The registers that showed up on the holding register scan using "MODSCAN64" were 400001 (duty cycle), 400017 (brightness), 400049 (ramp/brightness). Registers 400001-400016 are read/write, anything above 400016 are write only.

    Leave a comment:


  • bcarlton
    replied
    Are you trying to create Modbus/ASCII sequences using just the ASCII Send command? That is the protocol the MODSCAN application would have used.

    For the particular unit you might wish to use the OPTOMUX protocol

    http://documents.opto22.com/1572_Opt...ocol_Guide.pdf

    (start at Chapter 3)

    It appears easier and, for pure testing, you can substitute the characters '??' for the two checksum characters.

    (Note, I have only read brief parts of this manual, don't ask me for a Click application.)
    Last edited by bcarlton; 03-13-2016, 12:49 PM.

    Leave a comment:


  • Do-more PE
    replied
    Click will not talk MODBUS ASCII it only talks MODBUS RTU. Click ASCII is a raw non-sequenced stream of ASCII characters, not a protocol.

    MODBUS ASCII is an ancient version of the MODBUS protocol that isn't used much anymore.
    Last edited by Do-more PE; 03-12-2016, 04:26 PM.

    Leave a comment:


  • kewakl
    replied
    See Click help topic CL183.
    In CLICK help, got the Search tab. Enter CL183 in the search box.

    I can issue commands to the Opto 22 and have it respond correctly.
    Issue what commands?
    What did you put in the SEND block?

    Leave a comment:

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