4 Jun
2003
4 Jun
'03
12:57 p.m.
Hi,
Wandered downstairs, and dug out my pile of parts.
(and more importantly a spare ROM 01 system.) My testing was on a ROM 03.
Thanks for the parts offers, I think I've enough parts now though..
(The wife eye's me evilly every time I drag out my parts pile anyways :-) )
I checked the voltages.
The worst I saw as -10.2v (on what aledged to be the -12v pin) on the ROM03.
The ROM 01's voltages were all pretty normal.
There's nothing else plugged into the systems for the last couple of tests
I just ran. This scope I have is fairly old, and probably not terribly
accurate, but about the best I've seen is +/- 4.9v.
Neither the ROM 01, nor the ROM 03 will talk to the PC.
At this point, I'm wondering if the IIgs's normal "serial" is on the
low side of valid, and my PC's (mis)wired for the high side. I'll
try the serial ports on my Linux firewall.
Data sheet for the AM26LS30's on the thing doesn't make sense to me either
at this point.. but that's besides the point..
Anybody got a schematic for the whole GS? :-)
David
On Wed, 4 Jun 2003, Ian Primus wrote:
Sounds like a weak PSU, I have had no trouble using
ADT on a IIgs. How
much stuff do you have connected to it? I know I have found that after
two Unidisk 5.25's, two 3.5" drives, two Disk II's, a SCSI card, RAM
expansion, etc, etc, it the computer sometimes can't get the juice to
power drives, I/O, etc (especially those pesky Disk II's)... Try
measuring voltages at the power supply, it should have the pinouts
printed on it IIRC. If you want, I have a spare IIgs or two that you
can have for a few bucks plus shipping. I also have IIe's and floppy
drives as well, if you want.
Ian Primus
ian_primus(a)yahoo.com