I have a small collection of crt files and wanted to use them with my
retro replay. Most of them can not be flashed to the rr without
modification, but as I'm a lazy person I didn't want to patch every
single crt. CRT8040 is a generic solution for one special cartridge
type.
How does it work?
The crts I wanted to flash are mapped into the C64's mem starting at
$8000. Their length is $4000 bytes. Unfortunately the rr can just map
in $2000 bytes of rom at once, so the rest of the crt data will be
copied into the rr ram. A little reset routine will do this job.
It is implemented as a header which can prepended to the data section
of the crt file. Please take a look at the source for more details.
Download
Source
You will need DreamAss to assemble the source. Get it here.
The Makefiles heavily depend on Unix console tools like 'dd', they will
definitely not work with Windows. Please choose the binary distribution
for non-unix systems.
Extract the archiv somewhere and execute 'make' in the main directory.
The source will be assembled and all the .crt files in the crts
subdirectory will be converted.
The archive contains some demo roms in binary format. Use the flash
utility shipped with your retro replay to transfer them.
The demo roms:
Dragonsden
Gyruss
Hero
Miner 2049'er
Moon Patrol
Solar Fox
Wizard of Wor
Convert other crt files
To convert other cartridges, first make sure they are the right type.
This header can only be used for crts which start at $8000 and have a
size of $4000 bytes.
Check this in 2 steps:
The filesize must be 16464 bytes
Start your favourite hex editor / viewer and look for the byte
sequence $80 $00 $40 $00
around offset $4c.
Copy the .crt's into the crts subdirectory of the source distribution.
Execute 'make' in the above directory.
Feedback
The best place to give some feedback is the Retro Replay Mailinglist.
Go here
to get subscribed. If you own a Retro Replay this is a good idea anyway.
Please choose a private mail only for topics not suitable for the list.
