Zilog Discontinues the Z80 Microprocessor after 48 years!

[Chris Savage]

This is now somewhat old news, but I wanted to make sure I had the information here for search reasons.

https://www.allaboutcircuits.com/news/end-of-era-zilog-discontinues-z80-microprocessor/

Last Time Buy Notification (Mouser)

[granz]

I did see that - kind of sad.

That being so, I do have a couple (few?) Z-80 CPUs and other related chips. So, one of these days, I will need to wire up a Z-80 CPU tester board, and check them out.

[Chris Savage]

So, one of these days, I will need to wire up a Z-80 CPU tester board, and check them out.

For those who don't know, most Z80 test boards just have the CPU mounted in a socket with the clock input wired to a 555 timer, the data bus wired to all 8 bits low (NOP), and the address bus buffered into LEDs, so on startup the CPU essentially starts executing NOPs and you can see the address bus increment through the entire 64K address space.

Perhaps you could design something more robust that tests the stack and instructions and perhaps even the interrupts?

[JKnightandKARR]

Are there any similar cpu's that are kinda the same thing??

[Chris Savage]

Are there any similar cpu's that are kinda the same thing??

Probably, but there's going to be supply for a while. I'm good.

[granz]

Are there any similar cpu's that are kinda the same thing??

That depends on what you mean by "kinda the same thing." If you just want to run Z-80 programs, the Raspberry Pi Pico can do that with RunCPM (https://github.com/guidol70/RunCPM_RPi_Pico) or you can run CP/M on an Arduino (https://projecthub.arduino.cc/FoxyLab/arduino-nano-as-cpm-compatible-computer-b1300d). In fact, any processor that is Turing-complete can emulate any other processor. I remember someone emulating a Z-80 on an ATmega-88 controller (https://spritesmods.com/?art=avrcpm&f=had), although it was pretty slow.

If you are wanting more exact "kinda the same thing," then the eZ-80 (https://www.zilog.com/docs/um0077.pdf) is based on the Z-80 core, but adds microcontroller-like components, plus more memory, right in the chip. In addition, the Z-80 is still being produced by second-source companies (some mentioned here: https://tedium.co/2024/05/11/zilog-z80-history/.) The Z-80 is even being recreated as an Open Source project (https://savagechats.com/index.php?board=9;action=post2.)

Plus, as Chris mentions:

Probably, but there's going to be supply for a while. I'm good.

So, we still have a bit of a supply of the original thing. 

[JKnightandKARR]

Are there any similar cpu's that are kinda the same thing??

Probably, but there's going to be supply for a while. I'm good.

I've often thought of something like this: Z80 kit
Would that work??

Are there any similar cpu's that are kinda the same thing??

That depends on what you mean by "kinda the same thing." If you just want to run Z-80 programs, the Raspberry Pi Pico can do that with RunCPM (https://github.com/guidol70/RunCPM_RPi_Pico) or you can run CP/M on an Arduino (https://projecthub.arduino.cc/FoxyLab/arduino-nano-as-cpm-compatible-computer-b1300d). In fact, any processor that is Turing-complete can emulate any other processor. I remember someone emulating a Z-80 on an ATmega-88 controller (https://spritesmods.com/?art=avrcpm&f=had), although it was pretty slow.

If you are wanting more exact "kinda the same thing," then the eZ-80 (https://www.zilog.com/docs/um0077.pdf) is based on the Z-80 core, but adds microcontroller-like components, plus more memory, right in the chip. In addition, the Z-80 is still being produced by second-source companies (some mentioned here: https://tedium.co/2024/05/11/zilog-z80-history/.) The Z-80 is even being recreated as an Open Source project (https://savagechats.com/index.php?board=9;action=post2.)

Plus, as Chris mentions:

Probably, but there's going to be supply for a while. I'm good.

So, we still have a bit of a supply of the original thing. 

I mean, kinda like when Intel and AMD cpu's could work on the same system. 486 I think?? Basically a clone of the Z80 for later when they are gone.  You mentioned the ZX80/81 before, how much?

[granz]

If you are wanting more exact "kinda the same thing," then the eZ-80 (https://www.zilog.com/docs/um0077.pdf) is based on the Z-80 core, but adds microcontroller-like components, plus more memory, right in the chip. In addition, the Z-80 is still being produced by second-source companies (some mentioned here: https://tedium.co/2024/05/11/zilog-z80-history/.) The Z-80 is even being recreated as an Open Source project (https://savagechats.com/index.php?board=9;action=post2.)

So, we still have a bit of a supply of the original thing. 

I mean, kinda like when Intel and AMD cpu's could work on the same system. 486 I think?? Basically a clone of the Z80 for later when they are gone.

Yeah, like I said above, there are still second-sourced Z-80s being produced. The NEC 780 is one, and MOSTEK and Synertek are other companies producing them. As they are officially licensed by Zilog to produce the Z-80 chips, I'm not sure that the term "clone" would be most accurate. Although, I guess that it could apply.

In addition, the FOSSi Z-80 (Free and Open Source Silicon Z-80) is a current project, and is open for anyone to try out. So any one interested in obtaining a Z-80 still has at least three second-sources plus the ability to go into production on their own.

You mentioned the ZX80/81 before, how much?

Sorry, I can't figure out where they went - I'm still looking.