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Marsh
04-16-2012, 09:33 AM
So I finally sat down and started laying out my OC Mastercard.

The inputs side of things is simple...wire a switch between the pin you want to use and that groups GND pin.

The outputs side has both a GND and +5VDC. Searching this site I found an example of lighting an LED from this...they connect the LED to a pin they want to use and the GND pin. Looks like the individual pins are sourcing +5VDC then if a circuit is completed when connecting to GND. So what's the +5VDC pin for? Do I need to supply +5VDC to that pin?

fordgt40
04-16-2012, 11:03 AM
You must provide a 5 volt supply to the mastercard, Jumper J0. When you send an output high via sioc then that output will provide 5 volts, provided that the other end of the circuit is connected to gnd. Always provide a suitable size resistor in a led circuit to limit the current, else it will "blow". Its all in the latest version of the manual :)

David

Marsh
04-16-2012, 11:37 PM
I'm specifically talking about the +5VDC pins in the J2 and P1 output connectors. Perhaps it gives you a sinking or sourcing wiring option?

fordgt40
04-17-2012, 04:18 AM
Advice still stands, I assume that the voltage is there for "user purposes" on J2. The USBexpansion card has no need for 5 volts through P1 as it gets its supply via the USB

David