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Sony BRC-Z700 and RS-422 control

Has anyone controlled a Sony BRC=Z700 with RS-422? I had to fiddle around with the wiring to even get replies back from the camears. (Sony's documentation when it comes to pin-outs is abysmal!). Now all I get back from the camera is
Line 3 (16:57:52):: String From [5001:1:1]-[$DF$BF$FF]

no mater which command I send it. When the camera first powers on it sends me:

Line 5 (16:58:08):: String From [5001:1:1]-[$F7$D7$FD]

I've controlled other BRC's with RS-232 But not RS-422. It kinda has me stumped.
any help would be appriciated...Jim...

P.S. I did set the dip switch on the bottom to 422.


  • Options
    ericmedleyericmedley Posts: 4,177
    I would start with good ole serial troubleshooting.

    Try different baud rates. Sometimes the documentation is wrong.

    The usual advantage to 422 is that you can put more than one device on the comm buss. But all devices typically need and ID or address. This is usually set on the device itself.

    422 usually (but not always) has separate wire pairs for transmit and receive. Something like TX+/TX- and RX+/RX- I have seen some devices that you actually tie the TX and RX plusses and minuses together.

    You also might have a physical connection issue like a short or bad termination. It works just enough to pass a little voltage, thus giving you erroneous data.

    There's some hints....
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    HedbergHedberg Posts: 671
    Unfortunately, there is no standard definition of what RX and TX refer to nor with the polarity assignments, for 422. This is what I believe we found to work for Sony cameras:

    AMX Sony
    RX- TX+
    RX+ TX-
    TX- RX+
    TX+ RX-

    Best I can tell this should translate to the following pin connections (AMX DB9):

    AMX Sony
    1 9
    6 8
    9 7
    4 6
    5 5

    If you are using a COM2 card, check the documentation for the card to see which pin assignments are which for RS422.

    As mentioned by Eric, check your baud rate.

    Commands strings for RS232 and RS422 should be identical
  • Options
    Success! Thanks

    I tried all those things, I even tried banging my head on the wall! i tried all manor of rates and dip switch settings but to no avail. I figured it had to be a pin-out issue, I thought I had tried every combination, But I missed that one (thanks Hedberg). Love that Sony documentation!!
    Thanks again...Jim...
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    HARMAN_ChrisHARMAN_Chris Posts: 598
    edited December 2022

    An oldie but a goodie - thanks @Hedberg for putting this nugget out into the universe. I too was banging my head against the wall on RS422 wiring for a similar device.

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