23 Feb
2009
23 Feb
'09
11:35 a.m.
Christian Corti wrote:
We have several third-party ROM and RAM modules for our 4051. A RAM
module (called BACKRAM) behaves like a ROM module after you have
loaded the contents from tape. There is one module with support for
CBM drives, special I/O routines, assembler and firmware routines.
The documentation (alas German only) for these ROMs can be found at
ftp.informatik.uni-stuttgart.de/pub/cm/tek4051/
BTW it *is* possible to write 6800 programs, it's just not officially
documented. The magic command is
CALL "exec" [,{Var1} [,{Var2} {,...]]], {Loaderstring}
(see exec.txt and ram_loader.prg)
Wow, that's awesome! I'd worked out a bit of "exec" but this
will be
very helpful (assuming I can decipher enough of the German text to get
anything useful out of it :). (Google Translate seems to do a pretty
good job -- I'll clean it up and provide an English version when I'm done...
Thanks a ton!
Josh
I'm looking into whether if it's possible
to adapt one of the
"backpack" expansions to take EPROMs instead of MCM6832 ROMs. Anyone
done this before? Given a bit of hacking it'd then be possible to
write some 6800 code to do a binary dump of the tapes, bypassing the
protection mechanisms.
I've already written a little BASIC program that uses the special ROM
functions in order to create real tape dumps into a CBM floppy file.
These dumps contain all records etc., and it is possible to create a
real tape from that image. The commands are TREAD and TWRITE.
The file sysrom.txt contains a descriptions of the system ROM entry
points and the function they perform.
And here's how to un-secret a program (see exec.txt):
L$="7?008039"
CALL "exec",L$
Christian