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JonB
November 9th, 2018, 04:57 AM
Hi all

I've just completed re-engineering Bob Grieb's Tauntek 8080-ICE as he doesn't make them any more:

49248

49249

I've got permission to offer these, so is there any interest in this board or the Z80-ICE (which I plan to do next)?

Cheers
JonB

lowen
November 9th, 2018, 09:06 AM
Yes on the Z80 board. Nice work, by the way.

gekaufman
November 9th, 2018, 09:23 AM
Jon -

Nice work! I arranged a run of the original boards a while back. Unfortunately sourcing the original CPLD was difficult.

https://www.retrobrewcomputers.org/doku.php?id=builderpages:gary_kaufman:z80ice

I've had occasional requests from folks about availability, so I'm sure there will be interest.

- Gary

BloodyCactus
November 9th, 2018, 09:23 AM
Are not the XC9536's hard to get now they have been OOP for quite a few years? Do you plan on redesigning it to remove the obsolete parts?

JonB
November 9th, 2018, 10:51 AM
It was redesigned to take the 3.3v variant - 9536XL. There's a jumper onboard to set the CPLD voltage. The one pictured uses the PC44 package (socketed). It works with the 5v and 3.3v part. This means you can use whatever is available. The only fly in the ointment is that there are glitches with the MD and MT commands. I'm looking into it. Otherwise, it works fine.

To redesign for a newer CPLD would take a lot longer, because I'd have to learn more about CPLDs. But that doesn't seem necessary because I can still order the 3.3v CPLD in an SMT package from Farnell. So a board that can use these chips is do-able, at least for the time being.

ldkraemer
November 9th, 2018, 12:14 PM
JonB,
I'm interested in the Z80ICE (one or possibly 2).

Larry

glitch
November 12th, 2018, 03:57 PM
I'd be interested in one of each. Thanks for reviving this project!

I was over-excited to see "8008" in the title -- perhaps a moderator can correct that? :p

Dwight Elvey
November 13th, 2018, 06:15 AM
I've often thought about creating a CPU substitute for these older machine. For the most part, we rarely do development of Z80 and 8080 machines, we are mostly diagnosing and repairing these machines. For diagnosing, we rarely need to run the original code on the machine. In fact, the original code is a poor diagnostic tool. It rarely repeats a sequence but once on reset that we need to analyse. Any need for an ICE to develop a machine can usually be done with a ROM ICE ( a much simpler setup ). We have cheap controllers that run at 72Mhz or greater that can run I/O fast enough to run diagnostics on a 8080 or Z80 bus. The interface would be mostly buffers. No additional programmable devices are needed.
Dwight

Al Kossow
November 13th, 2018, 06:37 AM
We have cheap controllers that run at 72Mhz or greater that can run I/O fast enough to run diagnostics on a 8080 or Z80 bus. The interface would be mostly buffers. No additional programmable devices are needed.
Dwight

That's nice.
Why re-invent the wheel?
This is a solved problem.

BloodyCactus
November 13th, 2018, 07:05 AM
Im curious how well the 3.3v CPLD drives 5v TTL CPU lines and downstream TTL logic.

JonB
December 1st, 2018, 07:57 AM
@BloodyCactus: It just works.. :) The official level of a TTL "High" signal (according to Wikipedia) is from 2.0v - Vcc (5v), so a 3.3v high level would count as a 1 when read by a TTL IC. The CPLD only has to drive the first input signal of a TTL device; all ongoing signals would be at 5v. What is more important is the signals coming into the CPLD. If its (input) pins are not 5v tolerant there will be damage, but the part I am using (XC9536XL) is 5v tolerant.

8008guy
December 2nd, 2018, 07:36 PM
I'd be interested in one of each. Thanks for reviving this project!

I was over-excited to see "8008" in the title -- perhaps a moderator can correct that? :p

Yep, ditto on that