21 Oct
2004
21 Oct
'04
4:22 a.m.
At 14:34 21/10/2004 +0000, you wrote:
On Thu, 2004-10-21 at 07:39 -0400, Dave Dunfield
wrote:
Thats true, and there are other concerns - I've seen devices which go thermo
if there's no clock! - Thats why I do this only if I can't test the power
supply separately, and only power it very briefly - long enough to verify
the power rails.
Anything you would add?
The comment made recently about memory drawing excess current if inputs
are left floating is interesting though. Proof that you do need to know
about the system you're testing as taking the modular approach to
powering up doesn't always work and might actually do more harm than
good. The other thing I'd add to that is to always use a
dummy form of mass
storage in place of any real media, even after you're confident that the
power supply is OK - just in case on first full boot the system decides
to stomp all over the media.
Good point - I always disconnect drives etc. at first power-up, but one
area where I've seen people have trouble is in floppy disks - DON'T USE
THE MASTER DISKETTE ON FIRST ATTEMPT TO BOOT! I always try to find ways
to backup the disks and boot from a copy if at all possible.
I just got a Kaypro in where the guy had tried to boot it after it had
sat for a number of years, got a loud shrieking noise after which the boot
disk was missing a band of oxide - Fortunately, he had the sense not to
try another disk.
Regards,
Dave--
dave04a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools: www.dunfield.com
com Vintage computing equipment collector.
http://www.parse.com/~ddunfield/museum/index.html