That's why i suggested the 4066 chip... its a set of 4 PSDT switches that can be controlled seperately. when one of the buttons are pressed to open the tray you can have the IC cut power to/from the MOBO..
You are using a togle switch right? Then have power to the IC as one when the toggle is in the center position. Then the MB can control the tray.
what voltage are you planning to use for the motor?.... use that to also give the CMOC chip the on signal for the MB. I'd pair up the switches though. 2/4 for each of the wires for the motor.
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