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The Memotech MTX Series

Memotech Multi-Function Expansion System

MFX Firmware

MTX CFX Boot Screen

CF Card Directory

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This page is the repository for the firmware and custom software programs used by the Memotech Multi Function Expansion board, MFX. The PCB includes

  • A GAL22V10 that performs ROM and RAM decoding

  • A 128kB Flash ROM that contains the Z80 compatible system ROM functions

  • An Altera Cyclone II EP2C5T144C8N FPGA that contains the VGA drivers and other custom functions

(Some) source files are provided for reference, only the object files are actually required to perform the upgrades.



The GAL code is unlikely to change during the life of the product. The code references the hardwired connections to the MTX page port, some Z80 control signals (/RD and /MREQ), the configuration jumpers and the high order bits of the address bus. Unless an error in the paging logic comes to light, there should be no requirement to update the GAL. The GAL object files are JED files produced in  MicroChip's PLD programming application, WINCUPL.

The Flash ROM contains some enhancements to the SDX ROM. It is possible that some minor additional features could be added or errors discovered in the current ROM code. Should either of these occur, the ROM will likely be updated and made available for download on this page. Provided that the user has a suitable EPROM programmer, updating the ROM should be a trivial task, however, updated ROMs will be available for upgrade or purchase through the link at the bottom of the page.

The FGPA is mounted on a small development board piggy-backed on top of the MFX PCB. The FPGA contains the VGA and SD card drivers and other custom functions. It is possible that some minor additional features could be added or errors discovered in the current FPGA code. Should either of these occur, the FPGA code will likely be updated and made available for download on this page.

Upgrading of the FPGA code is a slightly more complex task than upgrading the ROM, it requires that the user has a copy of the Altera Quartus II design suite (a free version is available) and a suitable device programmer. Due to the orientation of the FPGA development board, it would need to be removed from the MFX PCB in order to perform the upgrade. It may be that the best way for the user to access an updated FPGA code version is to return the FPGA module to me to upgrade. There would be no charge for this, other than for the cost of return postage.


Download Description Version
Source Object Build Date
GAL Program
Initial release 1.0 26/03/22
Corrects a problem with the RAM paging logic 2.0 29/07/22
ROM Image
n/a Development 117 16/06/22
n/a Initial release - use with SD cards 1GB or smaller 134 11/07/22
n/a Beta version - adds limited support for SDHC cards
[Larger capacity SD/SDHC cards are now supported, but the maximum useable space (~270MB) is unchanged.]
Note: In this release, Hextrain can only be run from SD card
(Do not use : Replaced by Build 167)
166 25/09/22
n/a Updated beta version - corrects bug in USER VGA introduced in Build 166
Bill has now modified Hextrain to be able to use both SD and SD/HC cards. Bill's version, including sources and executables are available in this archive, or the SD executable is available below.
167 29/09/22
The FPGA binary includes a serial number generated at compile time which includes the owner's initials and a unique serial number. To keep these serial numbers accurate, generic downloads of the FPGA code are not available but I will generate an updated file for you on request.
Alternatively, you can return the FPGA board for upgrade as described above.
n/a Initial release (ASP .pof file)
01-00 17/07/22
n/a Corrects an error in the shadow Page Port logic.
Only affects boards with serial numbers below xx-10, and even then, most users will be unaffected by this issue.
01-01 27/10/22


The programs below provide support for the non-standard features of MFX, including the WIZnet Ethernet module and various other support programs. These programs were kindly developed by Bill Brendling.

Download Description Version
Source Object Build Date
in zip - Start .com games from CP/M
Puts the VGA screen into VDP mode before starting the game. Usage "cpmvdp"
1.0 18/06/22
in zip Updated ftpd and httpd to accept command line options to specify the default web server index filename (httpd only) and log file name
switch meaning example default
-h  index file name -h index.htm index.htm
-l log file name -l ftpd.log (none)
230307 07/03/23
in zip - File Transfer Protocol Daemon (MFX ftp host) - Http Daemon (MFX web server)
220530 30/05/22 - Hextrain for MFX with SD and SDHC Cards 211001 01/10/22


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