Need help with RS 485 and Dado Door

sijandi · May 2013

Is anyone familiar with the Dado Door product? Their installation manual says that they only use two pins for RS485 communication, "RJ45 pins: A=1, B=2, 3-8 unused." Am I right that this isn't typical? I'm wondering which would be the corresponding pins on an NI-4100 serial port.

Also, here is my usual Data Event handler for initializing serial ports, should I do it differently for this product? (Yes, the baud etc. are from their programming manual.)

DATA_EVENT [dvDADO_DOOR] //INITIALIZE RS232 PORT FOR DADO DOOR
{   ONLINE:
    {SEND_COMMAND DATA.DEVICE,'SET BAUD 9600,N,8,1 485 ENABLE'
     SEND_COMMAND DATA.DEVICE,'HSOFF'
    }
}

the8thst · May 2013

http://www.amx.com//assets/manuals/NI-X100.HardwareReferenceGuide.pdf
Page 25.

sijandi · May 2013

Thanks the8thst, it's been forever since I've read the hardware manual. When it says "strap to" does that mean I need to connect pin A on the Dado Door to both pins 1 & 9 on the NI-4100? That's my assumption but it doesn't hurt to double check.

Hedberg · May 2013

sijandi wrote: »

Thanks the8thst, it's been forever since I've read the hardware manual. When it says "strap to" does that mean I need to connect pin A on the Dado Door to both pins 1 & 9 on the NI-4100? That's my assumption but it doesn't hurt to double check.

Yes.

RS485 is half-duplex. Transmit and receive are on the same wires.

I don't understand how it works with just two wires, though. It's balanced and should use two wires plus ground, as I understand it.

Need help with RS 485 and Dado Door

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