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Building a Mac SE/30 with soft power on
Posted by: cheesestraws on 2022-08-29 08:06:20
Yes. This will not make your SE/30 magically sprout the hardware needed for soft power (I wish I could conjure things out of thin air like that 🙂 ). This is more so that people who have more time than me in the next week or so can see whether it makes the PWROFF line flap or not.
Posted by: amedeo_68k on 2022-08-29 09:38:37
@Phipli yeah, I just want to see if any signal is sent, if it is sent than we could think to make a really small board, probably a relay and few components
Posted by: Phipli on 2022-08-29 09:45:27
@Phipli yeah, I just want to see if any signal is sent, if it is sent than we could think to make a really small board, probably a relay and few components
Excellent, was just checking you didn't think it was a full solution. Let us know how it goes.

If the signal latches, an LED and a 1k resistor will be enough to confirm it works. If it doesn't latch... a scope or MCU with an interrupt set on an input, or a flipflop circuit or something, might be needed to see it.
Posted by: cheesestraws on 2022-08-29 09:46:35
I don't believe it latches, if I'm reading the code that drives it right.
Posted by: Phipli on 2022-08-29 09:48:54
I don't believe it latches, if I'm reading the code that drives it right.
Flipflop time then 🙂
Posted by: joshc on 2022-08-29 10:08:59
This has been explored before, not sure if the old thread has anything of use in it?

SE/30 soft power

I've been thinking about this for a long time... my idea is to keep the SE/30 (or any other Mac without soft-power) permanently switched on, but plugged into an external switching box, which would be little more than a relay, a flip-flop and a tiny PSU for them. This box needs two control lines...
68kmla.org 68kmla.org
Posted by: Phipli on 2022-08-29 10:46:29
This has been explored before, not sure if the old thread has anything of use in it?

SE/30 soft power

I've been thinking about this for a long time... my idea is to keep the SE/30 (or any other Mac without soft-power) permanently switched on, but plugged into an external switching box, which would be little more than a relay, a flip-flop and a tiny PSU for them. This box needs two control lines...
68kmla.org 68kmla.org
Thanks joshc - lots in there. Sounds like there was a surprise in that the via pin isn't actually connected to the PDS connector, but bbraun wrote this :


... which enables the functionality on an SE/30, at VIA2 at least. If I skim-read it right.
Posted by: amedeo_68k on 2022-09-21 01:40:11
Hi all, I haven't got time yet to try, but next week I should be able
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