It's been a LONG time since I've signed on, let me tell you! It's been years, hehe. Anyway, I've been wondering about something.
On the Macintosh LC/Performa 5xx/6xx series, I've read that as long as the power button on the back of the unit is turned on, there is trickle voltage supplied to the motherboard (I assume a trivial amount). How is this voltage supplied? I am trying to figure out whether the power is supplied directly through the designated power wires (yellow, red) or rather supplied separately through a different wire on the wiring harness? Also, how much is supplied, 5v, 12v? Is the trickle voltage also related ot the "Soft Power On" rather than just maintaining the PRAM?
When talking about the LC 500 series and the CC respectively (built-in screen), I know that power is supplied by the analogue board of the system via the analogue board connector. The analogue board connector also provides additional wiring going from the logic board up to the analogue board for different reasons, such as video, audio, etc. but some pins also seem to carry current (+5v, -12v). What are these used for?
Also, when using the "Soft Power On" key to crank up the system, what exactly happens in the system (how does the PSU know that it needs to cut on, how does this information reach the PSU from the logic board). Is there a specific pin on the logic board that controls this? I've been Googling on the web for ages for information but it's rather scarce.
I know I have a lot of questions and I'm not expecting all these to be answered, but I'd love to hear from you guys