Archive of Atari 8-bit ROMDOS/RDOS related ROMs and boot disks, including disassembly and new experiments.
Run with atari800 emulator:
atari800 -nopatch -nopatchall -xl -xlxe_rom romdos-xl-osb.rom -xl-rev custom -cart roms/basicrevc.bin -cart-type 1 atr/romdos.atr
Or with atr/formatted+dupr.atr, romdos-bootcode-dupr.atr or romdos-singlesector-dupr.atr
atr/ contains the "original" romdos atr and images formatted by it plus helper files
bootcode/ disassembled and annotated boot code, and newly written experimental single sector boot sector
dat/ contains data files, for example the SD 720 sectors ATR header
roms/ ROM dumps, including the 4kB RDOS V0.1 ROM
/ scripts to generate a new "fake" 16kB XL ROM that includes the ROMDOS ROM, ATR images with the original boot code reassembled, and an ATR with the experimental single sector boot code.
You need a proper Linux/Unix command line or perhaps WSL2 on Windows. Furthermore, you need mads to be able to assemble the 6502 source files.
Built from source romdos-bootcode-dupr.atr is binary identical to a disk formatted by RDOS with three boot sectors and DUPR.SYS written to it.
$ ./build-bootcode-atr.sh
Writing object file...
430 lines of source assembled in 3 pass
384 bytes written to the object file
Files atr/formatted+dupr.atr and romdos-bootcode-dupr.atr are identical
The experimental single sector boot disk seems to work like any other RDOS disk. Loading and saving files all works. That's good.
There is one limitation, though. It is NOT possible to write DOS files to a newly formatted disk because the single sector boot code is not present in the original ROM. But the ROMDOS code writes its boot sector mostly from ROM. Hence the result is not bootable.
Start new single sector boot disks by making a copy of romdos-singlesector-dupr.atr.
Single sector boot disks only work with a ROMDOS ROM present. If it is not found, it will show an error message on screen.
disect AUTORUN.SYS that is in romdos.atrAUTORUN.SYS is a serial R: handler for MyDOS- investigate supercart ATR
Booting atr/romdos.atr
Booting atr/formatted+dupr.atr, romdos-bootcode-dupr.atr and romdos-singlesector-dupr.atr
Booting romdos-singlesector-dupr.atr without ROMDOS present
