[Coco] "Mini DOS" in early CoCo disk programs...
robert.gault at worldnet.att.net
Sun Jun 25 07:51:20 EDT 2006
Rogelio Perea wrote:
> What was the purpose of having a "mini DOS" program loaded in early
> CoCo disk programs? I refer to the program writen by R.G. Kilgus and
> that had to be loaded in software pieces like Disk EDTASM and Disk
> Profile for example...
It provides functionality that did not exist in the standard DOS.
Personally, I did not care for it and wrote my own disk I/O routines or
linked into the standard DOS. However, if you want to use the Tandy
code, you must test for the presence of DOS 1.0 or 1.1 and use the
There is a major drawback to Disk EDTASM using the Kilgus code while
EDTASM is running. Emulators, for the most part, do not correctly follow
the Tandy specs for directory entries. As a result, you can have
problems loading EDTASM source code into EDTASM under emulation. The bug
is that emulators do not make the 2nd 16 bytes of a directory entry all
This bug strikes primarily with a newly created .dsk image when PORT
or a similar utility is used to load the image with files. The second
sixteen bytes of the directory entries are left as $FF $FF $FF etc. and
EDTASM will not load any source files from the image.
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