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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 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.
Connect the Anode of the LED to pin 8 (PWR), and Cathode to pin 14 (GND). We recommend using a 10-100 ohm series resistor to protect the LED. The LED will be ON and will stay ON because pin 8 is always 3.3V and pin 14 is always GND. Use this to verify that the LED is working and that there is board power.
Connect the Anode to pin 15 and leave Cathode connected to pin 14 (GND).
You can now control the LED with a BrightAuthor:connected project, BrightAuthor project, or script. If the LED is too dim, remove the series resistor, as the board has an internal 100 ohm series resistor to limit current to the LED.
Connecting to 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
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