A tale of woe, including carelessness, stupidity and laziness....

[Jon Elson]

On 08/22/2015 02:41 PM, Jay Jaeger wrote:
> Thanks. Really, such mistakes aren't too demoralizing if 
> one can get the parts, get them in a reasonable amount of 
> time, at a reasonable price, and have the skill to do the fix
One of the biggest oopses I ever had was I got a Memorex 10 
MB hard drive with SASI controller for my S-100 /CP/M 
system.  I had just gotten it very roughly working, when I 
was fiddling with something and the SASI controller touched 
the drive and there were sparks.  I did the finger test 
first, and replaced all chips that were sizzling hot.  Then, 
I went through, looking for bad logic levels, and replaced 
the chips driving those signals.  Then, when I still had bad 
logic levels, I replaced the chips receiving those signals.  
All the time I was worred that it might have popped one or 
more of the microcode ROMS.  Well, after some more 
replacing, it finally came back up, and the CP/M OS I had on 
the drive still worked!

I guess I've had a few more cases where something went poof, 
but that is one of the ones I still remember well.

Jon