Need help with RS 485 and Dado Door

sijandi

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

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

sijandi

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

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.