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Re: 2 different "Z80 CPU BOARD VERSION 02" pcbs out there

I figured out what my problem was.  The Jade NOS backplane I was using was
not completely S100 standard compliant.  Pin 3 (XRDY) is tied to ground on this
backplane, pulling wait low and locking up the cpu.

I cut a few traces, and the problem is solved.

I guess you really have to be aware that some of the older stuff may not 
adhere to the standard.


On Saturday, August 9, 2014 12:54:36 PM UTC-5, Edward Snider wrote:
Hello all,

I am in the process of trying to get my Z80 cpu card running, and I've noticed that 
there are definitely 2 different pcbs marked "Z80 CPU BOARD VERSION 02",
I have them both in front of me.

The one I built does not have a JP10 or K3 jumpers.  Is this actually a V1 board then?
I'm trying to figure out which schematics I should be looking at.

Anyone know of any other differences, jumper settings, issues, etc, I should be aware of
with this board?  So far I'm just trying to get the cpu into halt with an eprom full of 76's
and not having any luck.  Probably don't understand the jumper settings well enough.