YAZE-AG - Yet Another Z80 Emulator by AG (V 2.20.1)

(HTML - Documentation)


yaze-ag is designed to provide an exact simulation of the Z80 microprocessor on a

It is fast, emulates undocumented opcodes, and passes instruction regression tests against real Z80 hardware.

NEW in yaze-ag version 2.xx is the support of an emulated Memory Management Unit (MMU) and the BIOS which supports CP/M 3.1 .

YAZE-AG is a Z80-CPU-Emulator and NOT a CP/M-Emulator!

Inside the Emulator runs an original CP/M or a replacement of CP/M.

YAZE-AG uses the free CP/M 3.1 replacement "ZPM3N10" of Simeon Cran (bootfile "yaze-cpm3.boot") or the CP/M 2.2 replacement "Superdos" (bootfile "yaze.boot").

How do you find new versions and the web page of YAZE-AG?

For detail information and new versions look to the web page of YAZE-AG


it's a redirect to

http://www.mathematik.uni-ulm.de/users/ag/yaze-ag/ (the original page at the University of Ulm, Germany)

An another way to find the web page of YAZE-AG is a search with Google. Give the search pattern "z80 emulator" and the link to "YAZE-AG - Yet Another Z80 Emulator by AG" is in the first page of the search results.
(Google uses only the second link.)


I took the idea of the page tables from Michael Haardt (look "Older version") and developed the MMU in YAZE-AG-2.xx.

This version runs CP/M 3.1 or ZPM3. I made a lot of changes in all modules to embed the MMU in the whole system and added the new module mem_mmu.c/mem_mmu.h.

In the BIOS3 (*.Z80-files) and the yaze-bios (bios.c) I support also special features of CP/M 3.1 like date, disk-change, xmove and multi-I/O.

Yaze-ag-2.20.1 is a final release. I believe this version runs quite stable. Since the pre release 2.00 I got many positive feedbacks and three bug reports (look "Fixed Bugs" in yaze-ag.doc). The reread bug of connected (unix-/windows-)directories is solved!

Support of serial lines in final release 2.20.1

Bugfix in release 2.12.1

NEW Features in release 2.12

I will announce new versions in the NETNEWS in comp.os.cpm !

If you find an error feel free and send an email to me.

Tip: Run the new emulator and give the command "help yaze-ag support". ;-))

Or have a look to the documentation (in HTML) which belongs to the new tar archive or to the new standalone binaries for windows. Or look to the end of this document.

yaze-ag-2.xx is a further development of yaze-1.10 (look "older versions" on the web page of YAZE-AG).


BOOTSYS relocates the resident and banked part of a CPM3.SYS to their places into memory and starts CP/M 3.1.

I develop it because CPMLDR of DRI/Caldera and ZPM3LDR of Simeon Cran does not work with the big CPM3.SYS file (43 KB) in yaze-ag.

Documentation of YAZE-AG-2.20

08. June 2008

Diplom-Ingenieur (FH) Andreas Gerlich

(University of Ulm, Germany)

IRC: agl @ IRCNet

only text emails please: (SPAM-Account)

( Last change 08. June 2008 )