MCLZ8 - Zilog Z80 Emulator in TRS-80 Model III

I wanted to share my latest project, the MCLZ8, which is a Zilog Z80 emulator which can be used as a drop-in replacement for the original Z80.

My Wordpress blog can be found here: MCLZ8 Link

For now, the MCLZ8 is running as a cycle-accurate Zilog Z80; however the next (fun) step will be to start integrating stuff like the TRS-80’s RAM and ROMS and running/caching them at the full speed of the 800Mhz Teensy microcontroller to see just how fast we can make this TRS-80 Model III, and see how it compares to the the accelerators which were available back in those days!



Nice work! It will be interesting to hear about acceleration performance.

Perhaps see also this previous thread:

Preliminary results indicate that the MCLZ8 is more than 15 times faster than the stock Z80 in the TRS-80 Model III… This is with cycle accuracy disabled and both ROM and RAM running at the microcontroller’s top speed… More testing needed, but it looks promising…

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More application testing results for the MCLZ8:

What about using it as a replacement for a Z80 in other Z80 machines?

Aside from BUSREQ/BUSACK signals the MCLZ8 is drop-in compatible to any Z80 socket.

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Nice project! The Teensy 4.1 is one of the few high performance boards that only rarely goes out of stock. The manufacturer did some clever planning and took a gamble on securing enough processors that he can meet steady (if not expanded) demand.

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I posted some videos of a few games and also a quick demo of the degree of acceleration achieved with the MCLZ8.

Posted on my blog here: MCLZ8 VIDEOS – GAMES AND Z80 ACCELERATION

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Project files are now on GitHub: MCLZ8 Github​​​​​​​

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I integrated the TRS-80 Model I ROMs into my MCLZ8 Z80 emulator and mapped the UART to the TRS-80’s keyboard and video RAM and now have it running on a standalone Teensy 4.1 board!