I dedicate the new version 2.51.2 to Jon Saxton.
He wrote the keytranslation
module which was the new feature of the version 2.40.5.
He passed at June 15, 2015 after a tough battle with cancer.
The last email I got at May 30, 2015 from Jon Saxton.
yaze-ag is designed to provide an exact simulation of the Z80 microprocessor
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").
I took the idea of the page tables from Michael Haardt (see "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
In the BIOS3 (*.Z80-files) and the yaze-bios
(ybios.c) I support also special features of CP/M 3.1 like date,
disk-change, xmove and multi-I/O.
Yaze-ag-2.51.2 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 (see "Fixed Bugs" in
The reread bug of connected (unix-/windows-)directories is solved!
Final release 2.51.2 is out (2022-01-01)
I add the Z80/Z180/Z280 Assembler "ZSM4". ZSM4 is a free Macro Assembler.
The Assembler is created by Hector Peraza. The project page is on
The licence is the GPLv2 (General Public Licence Version 2). The source files
of this Assembler can be mounted on drive O:.
This Assembler is now the standard for assemble BOOTSYS and the BIOS3-Z80 files
for YAZE-AG (see drive P:).
Final release 2.51.1 is out (2021-08-03)
Following new features are realized in version 2.51.1:
For calculation of the speed of the z80 core there is the submit
file "A:TESTZEX.SUB". It runs the Z80 core tester "ZEXALL.COM" and
measure up the time how it's needs and then it calculates at
the end the speed of the Z80 core.
A window size handler which automatically sets the line and column
of the used terminal emulator in the SCB of CP/M 3.1. This allows
that the CP/M-3 system-utilities (like type.com, dir.com, ...)
and the patched wordstar 4.00 (see drive A:) setup the screen
automatically like the coordinates of the used terminal emulator.
This allows you to use a terminal emulator until 99 lines and until
You can define a clockrate (e.g. 4000 kHz (4.0 MHz)) in the
monitor and the emulator runs at this frequency. This allows you to
play games which are developed e.g. for 4, 8 or 12 MHz. You can
also define a clockrate like "3957" which means 3957 kHz
Keytranslation: Begin with a new development cycle of version 2.32-xx (2015-01-14)
Further upgrades from Jon Saxton (Austalia) (development version 2.32-09, 2015-05-08).
Final Release 2.30.3 (2014-01-24) (without keytranslation)
Added a Makefile for the
Raspberry Pi 1
to compile YAZE-AG on a Raspberry Pi computer.
There is a detail description how you install YAZE-AG on a
Raspberry Pi 1 in INSTALL-2.30.3.
Final Release 2.30.2 (2013-11-20) (without keytranslation)
Some bug fixes (date calculation routine was wrong) and update
Now you can export files to the host system with the W.COM
utility without exiting the emulator.
With the R.COM utility you can import files from the host system.
Mr. Jon Saxton (from Australia) expand the project with
it is possible to use the cursor keys for example in an editor
like WS or Turbo-Modula-2 or ZDE.
The development goes on.
The last stable version is the final release 2.30.3.
Support of serial lines in final release 2.20.1
since version 2.20.1 the emulator uses the serial lines
of the PC (/dev/ttyS[0-3] in Linux or COM1-4 in Windows) to
communicate with other computers
(like with my new old real Z280 system
which I got on the www.zfest.de in 2007).
The new feature is described in "Serial Lines"
Kermit.com and rz.com/sz.com are on the disk file "Kermit_SZRZ.ydsk".
On Sun machines you can use the serial lines via the device /dev/ttya or /dev/ttyb.
I haven't tried if a Mac with serial ports works.
If anybody wants to do that for me, please give me back
a note how it works.
I fix a severe bug in the code connecting (Unix-/Windows-)directories
to a CP/M drive (see "Fixed Bugs"
Number 4 in yaze-ag.doc).
It was by chance that I found this bad bug.
Since release 2.20 I name all YAZE-AG-Disk-Files with the extension ".ydsk".
Bugfix in release 2.12.1
Jim Donoghue (USA, Houston, Texas) reports a bug in the
Z80 assembler instructions OUTI and OUTD. This is fixed in
release 2.12.1 .
NEW Features in release 2.12
I added the feature to put the time stamps of the (unix-/windows-)
files into the simulated CP/M directory of a CP/M drive which is
connected to a (unix-/windows-)directory.
"Mounting Directories with Time Stamps"
in yaze-ag.doc describes this new
feature (version 2.10).
The Z-System now works with yaze-ag (version 2.10) !
DOS-Character set enabled in the version for Windows (version 2.12).
I will announce new versions in the NETNEWS in
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 see the documentation (in HTML)
which belongs to the new tar archive or to the new standalone binaries for
yaze-ag-2.xx is a further development of yaze-1.10 (see "older version").
My English is not that good. I would be very delighted if anybody read my
documentation and give a feedback. The documentation which I wrote is
INSTALL-2.20, parts of
yaze(1), README-2.20, yaze-ag.doc, README_BIOS3_Z80 and README_BOOTSYS.
(Tip: Use the document files in yaze-ag-2.30.3.tar.gz ;-))
BOOTSYS - CPM3.SYS loader (V 1.31; October 12, 2021)
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.
With Bootsys You can restart CP/M 3.1 under CP/M 3.1/2.2 itself (cold boot)!
I dedicate this version to Jon Saxton.
He wrote the keytranslation Module in version 2.40.5.
He passed at June 15, 2015 after a tough battle with cancer. The last
email I got at May 30, 2015 from Jon Saxton.
The submit file "A:TESTZEX.SUB" runs ZEXALL.COM (Z80 core tester) and prints at the end the speed of the emulator.
(Set with "sys clock 0" the emulator to max speed.)
A window size handler which automatically sets the line and column of the used terminal emulator in the SCB of CP/M 3.1.
The patched Wordstar 4.00 (see A:)
and the CPM 3.1 system utilities uses the two variables over the standardized
BDOS-interface (call to 0005H) to setup the screen.
You can define a clockrate in the monitor (e.g. "sys clock 4000" for 4000 kHz
(4.0 MHz)) to run the emulator at this frequency.
The new feature of version 2.51.2 is:
The free Macro Assembler "ZSM4" is now the main Assembler in this project.
This Assembler is a Z80/Z180/Z280 Assembler and is coded in Z80 code.
The licence is the GPLv2 (General Public Licence Version 2).
The source files of this Assembler can be mounted on drive O:. This Assembler is now the
standard for assemble BOOTSYS and the BIOS3-Z80 files for YAZE-AG (see drive P:).
This new features are described in chapter 11., 12., 13., 14. and 15.
(Source for Unix / Linux / FreeBSD / MacOSX /
Cygwin / Raspberry Pi 1,2,3B,3B+,4B (32Bit and 64Bit) / BananapiM3 BPI-M3 / Orange Pi Plus / Radxa Rock).
In this version you can mount UNIX-/Windows-directories to
You can mount disk files (.ydsk) up to 64 MB.
I support here also the Raspberry Pi 1,
the Raspberry Pi 2 Model B,
the Raspberry Pi 3 Model B/B+ (32 and 64 bit),
the Raspberry Pi 4 Model B (32 and 64 bit),
the BananapiM3 BPI-M3,
the Orange Pi Plus/Plus2
and the Radxa Rock serie
Have a look to ChangeLog to see what is
new in this release!