Many years ago, I would guess in the mid '90s, I remember reading a book on the Z-80 on the trolley, on my way home from work. I remember that it had a schematic for a bare-minimum Z-80 system. The Z-80 was on the left side of the diagram, and it had some kind of ROM on the right - maybe a 2708. The I/O was just two 8-bit (or was it 4-bit) latches, one for input, and one for output (or maybe just the output.) The I/O latch(es) was/were below the ROM. There was no RAM - the author said that you can actually use just the registers for storage - as long as you don't use the stack. This was just the minimum system, but IIRC the book built on that to give a full Z-80 computer.
I remember that when I got home, I mentioned to my wife that I could build a music box from a system like that.
I have searched all the books that I have (list below) but none have that schematic. Do any of you remember (or can find) the book with that schematic?
Books that I have, and have checked out:
- Barden's The Z80 microcomputer handbook
- Barden's Z-80 Microcomputer Design Projects
- Blunk Electronics' How To Program the Z80 Periphery Tutorial
- Ciarcia's Build Your Own Z-80 Computer
- Dalton's 30 Customized Microprocessor Projects
- Gaonkar's The Z80 Microprocessor: Architecture, Interfacing, Programming, and Design
- Levinthal's Z80 Assembly Language Programming
- LJ Create's An Introduction to Z80 Microprocessor Applications
- Osborne's Z80 Programming for Logic Design
- SGS's (a Zilog second source provider) Z80 Microcomputer System
- Tedeschi's 101 Projects for the Z80
- Zak's How To Program The Z80
- Zilog's Z80 CPU Technical Manual*
- Zilog's Z80 Family CPU User's Manual.
*Note - Zilog's
Z80 CPU Technical Manual does have a similar schematic on page 59, but I'm pretty sure that I did not have a paper copy of that back in the '90s. That Zilog schematic also uses a Z80 PIO, rather than the latches that I remember (of course my memory may be playing tricks. ??? )
Quote from: granz on Jan 28, 2026, 12:48 PMMany years ago, I would guess in the mid '90s, I remember reading a book on the Z-80 on the trolley, on my way home from work. I remember that it had a schematic for a bare-minimum Z-80 system. The Z-80 was on the left side of the diagram, and it had some kind of ROM on the right - maybe a 2708. The I/O was just two 8-bit (or was it 4-bit) latches, one for input, and one for output (or maybe just the output.) The I/O latch(es) was/were below the ROM. There was no RAM - the author said that you can actually use just the registers for storage - as long as you don't use the stack. This was just the minimum system, but IIRC the book built on that to give a full Z-80 computer.
I remember that when I got home, I mentioned to my wife that I could build a music box from a system like that.
I have searched all the books that I have (list below) but none have that schematic. Do any of you remember (or can find) the book with that schematic?
Books that I have, and have checked out:
- Barden's The Z80 microcomputer handbook
- Barden's Z-80 Microcomputer Design Projects
- Blunk Electronics' How To Program the Z80 Periphery Tutorial
- Ciarcia's Build Your Own Z-80 Computer
- Dalton's 30 Customized Microprocessor Projects
- Gaonkar's The Z80 Microprocessor: Architecture, Interfacing, Programming, and Design
- Levinthal's Z80 Assembly Language Programming
- LJ Create's An Introduction to Z80 Microprocessor Applications
- Osborne's Z80 Programming for Logic Design
- SGS's (a Zilog second source provider) Z80 Microcomputer System
- Tedeschi's 101 Projects for the Z80
- Zak's How To Program The Z80
- Zilog's Z80 CPU Technical Manual*
- Zilog's Z80 Family CPU User's Manual.
*Note - Zilog's Z80 CPU Technical Manual does have a similar schematic on page 59, but I'm pretty sure that I did not have a paper copy of that back in the '90s. That Zilog schematic also uses a Z80 PIO, rather than the latches that I remember (of course my memory may be playing tricks. ??? )
The only book on the Z80 I have is that one collage text book...
Quote from: JKnightandKARR on Jan 28, 2026, 05:44 PMThe only book on the Z80 I have is that one collage text book...
Do you have a link to the book, or the title and author?
Quote from: granz on Jan 28, 2026, 05:48 PMQuote from: JKnightandKARR on Jan 28, 2026, 05:44 PMThe only book on the Z80 I have is that one collage text book...
Do you have a link to the book, or the title and author?
It's post #3 on here:
https://savagechats.com/index.php?msg=3486 (https://savagechats.com/index.php?msg=3486)
Quote from: JKnightandKARR on Jan 28, 2026, 06:36 PMQuote from: granz on Jan 28, 2026, 05:48 PMQuote from: JKnightandKARR on Jan 28, 2026, 05:44 PMThe only book on the Z80 I have is that one collage text book...
Do you have a link to the book, or the title and author?
It's post #3 on here:
https://savagechats.com/index.php?msg=3486 (https://savagechats.com/index.php?msg=3486)
Ah yes, I have that book (sixth book in my list above,) but sadly it is not the book that I want. Thanks though.
Hi
@granz , have you checked the Internet Archive, they have some interesting links for books and videos on building around the Z80
https://archive.org/
Quote from: Jeff_T on Jan 29, 2026, 05:16 PMHi @granz , have you checked the Internet Archive, they have some interesting links for books and videos on building around the Z80
https://archive.org/
Strange, I went to that search page, and selected .PDF collection. Every hit that I tried took me to a "cannot find server" notice - each one different. I have never had so many false hits at the Internet Archive. A couple of them even tried to send me to porn, or gambling sites.
Do you have any specific books that you have seen with circuits for minimal Z80 systems?
@granz yes I logged in today and saw a few sketchy sights come up in the search page. Not knowing the title of the book and not knowing what I am searching for is a big issue but I did find a couple of videos that looked interesting.
https://www.youtube.com/watch?v=5lsjD1cuq5Y&list=WL&index=1
https://www.youtube.com/watch?v=OtpaY8VD52g&list=WL&index=2
That second link is to a kit similar to this one (https://savagecircuits.com/rc2014-pro-homebrew-z80-computer-kit/) that I have built on Savage///Circuits.
The first link is closer to this project (https://savagecircuits.com/z80-retro-computer/) from Savage///Circuits.
The homebrew kit is still available on Tindie
https://www.tindie.com/products/semachthemonkey/rc2014-pro-homebrew-z80-computer-kit/
and it looks like you have the other project pretty well documented Chris
Quote from: Jeff_T on Jan 30, 2026, 01:46 PMThe homebrew kit is still available on Tindie
Yeah, I got my kit from Tindie. I think I linked the seller at the end of the project article.
Jeff, yeah, I've been keeping an eye on RC2014 since that challenge (wow, has it really been over twelve years that I have been following Retro Challenge? :o )
Unfortunately, due to the damage to my spinal cord, my soldering days (at least for that many solder connections) is pretty much over. I will need to stick with my RunCPM on my PicoCalc, and other emulators.
Actually, the reason that I wanted the schematic was for something that Chris and I were noodling (https://savagechats.com/index.php?topic=521.msg3982#msg3982.) Just what the well dressed hacker wants. 8)