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If you want to connect another player, then the output is capable of sourcing or sinking up to 3.3V at 24mA, but there is a series resistor of 100Ω in each line. The connector also allows the connecting of external contact closures to the ground.
Example
To See the steps below to connect an LED to the player GPIO connector (DA15), see the steps below. Once youwire the anode to pin 8 for testing, the LED anode is wired to a pin like the buttons. BrightSign players support 3.3v LEDs directly, without external power.
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