22 Nov
2001
22 Nov
'01
8:43 a.m.
On Thu, 22 Nov 2001, Tony Duell wrote:
>
> >I have a non working 128k unit I'd sure like to get around to fixing...It
> >actually worked before I located a keyboard and mouse for it, I think I
> >used the wrong type of keyboard cable. When I powered it up with the
> >keyboard, heard a snap, and it didn't work anymore :/
>
> YIKES!
Has it been established through all this dialogue that the machine will
still boot? If so, I have missed it.
- don
Yeah, the
keyboard cable is supposed to be straight pinned (or was that
cross pinned... no it was straight pinned). A standard phone cable is
It's straight through. certainly.
cross pinned (or was that straight pinned... no
was cross pinned... LOL).
If you use a standard phone cable, you will fry the keyboard controller
chip. I am sure that was the snap you heard.
Yes, you swap round +5V and ground at the keyboard. This is likely to
kill he microcontroller (8021 in early keyboards, 8048 in Mac+ keyboards
IIRC).
You can always use the mouse and the Key Caps
desk accessory, type by
clicking the letters, then choose cut and paste to move it to whatever
you are trying to type in... PITA, but it actually does work (I had to do
it once when my sister took the keyboard away from me, and I had to get a
The keyboard protocol is documented in Inside Macintosh IIRC. I am
wondering if it would be quicker to use the Key Caps DA to type a
reasonable amount of text or convince some other machine to pretend to be
a keyboard. Preactially, I hate repetitive jobs, so I'd probably have a
go at the latter (and if the school paper had been anything remotely
technical and I'd not finished it in time, I'd have explained my
attempted hack to replace the keyboard and hoped that the teacher would
understand :-)).
paper finished for school... it took me all
night, but I finished it...
and promptly beat the stuffing out of her the next morning)
Seems entirely reasonable :-)
-tony