Finally after 8 months, I found a way to add the FM Music ROM to my FS-A1FX.
I spend almost all time on finding a way to add a physical Eprom to my machine by reverse engineering a FS-A1WSX, but without luck.
I guess the M60014 Gate Array in the FX does not contain the extra address lines needed to address the extra Rom’s that the WSX uses.
Today I tried a different approach by Dumping the FX Rom using my Eeprom Programmer and simply cut and past the Music Rom into it.
To make this work I had to find out where to put the Music Rom. This Rom has a size of 16kb*8 within the 256kb*8 (2Mbit) FX Rom. One of the most annoying things (for European Users) of the Panasonic machines is the build in software Cockpit. 32kb*8 in size.
So I decided to replace the Cockpit Software with the Music Rom. To make this magic happen I used the XVI32 Hex editor. Using a dumped Rom of the Cockpit software I could easily find the memory block that the Cockpit software uses. In the physical Rom the Cockpit software is in block $20000 – $27FFF
I copied the MSX Music Rom into this block and burned the modified Rom into a M27C2001 Eprom.
I’ve put this Rom back into my FS-A1FX an here is the Result:
A perfect FS-A1FX:
- Build-in FM Music
- No Cockpit
- 512Kb Memory
- 2x 720kb DD Diskdrives