GPIO: Which pins correspond to which buttons?

Last Updated: October 19, 2016

The following table describes the outputs (numbered left to right) on the 12-pin GPIO for Series 3 players (XTx43, XDx33, HDx23):

The following table and diagram illustrate the pinout of the DA15 GPIO connector on earlier models: 



The Switch/LED connector is a DA15 Female. This connector is used to allow the BrightSign to control external LEDs or other devices requiring 24mA of current or less.

In order to connect an LED:

  • Connect the LED outputs to the LED ANODE
  • Connect the LED CATHODE to ground. 

If you want to connect another device, then the output is capable of sourcing or sinking up to 3.3V at 24mA, but there is a series resistor of 100W in each line. The connector also allows the connecting of external contact closures to the ground. 

In order to connect a switch:

  • Connect one side of the switch to the switch input
  • Connect the other side of the switch to one of the ground pins on the DB15 connector

The connector can also supply 3.3V at up to 500mA to an external device. The 3.3V output is polyfuse-protected and can source up to 500mA. If one BrightSign player is driving the inputs on another BrightSign player, then you can drive at most three inputs from one output. The following calculations explain this limitation:

Note: The GPIO outputs have 100W series resistors; the GPIO inputs have 1K pullup resistors to 3.3V; and the input threshold on the 541 chips is 2V high and .8V low. The high voltage is not problematic, but the low voltage can be if there are too many inputs connected to one output.


Have more questions? Submit a request


  • 0
    Jean Michel

    The text "is a series resistor of 100W" makes no sense. Perhaps you mean 100 Ohm?

  • 0
    David Ebaugh

    Is there any electrical problem with attaching a single switch on multiple BrightSigns in parallel?

    i.e. Switch is wired to "Button 1 I/O" on 4x HD1022's.  This is to execute the same programming on all 4 HD1022's upon pressing button 1. 

  • 0
    Adam Kaczmarek

    David Ebaugh I don't know will there be any electrical problem with setup you mentioned. However you could connect switch to a single BrightSign player (master) and send from it a sync signal to other BrightSign players.

Please sign in to leave a comment.
Can't find what looking for? Try to
Powered by Zendesk