DOS >2.0 Device Driver Info Wanted

[g-frank at gumby.UUCP]

> 
> 	I am looking for some good reference material on writting systems 
> driver in 8088/86 assembly (IBM Masm), or in C code (CI86 or 
> Lattice).  If anyone knows of any publications that explain this area
> of DOS, or have any sample programs that they would be willing to share.

Try the 'Disk Operating System Version 3.00 Technical Reference,' IBM part
number 6322677, or the very old DOS 2.0 manual, which contained the tech
ref material originally.  These both contain a startling amount of inform-
mation on the device driver interface.

The 2.0 manual contained a listing for a sample ramdisk driver; DOS 3.0
has the driver, and its source, on disk.

It may be possible to write such a driver in C, although it might prove
a bit tricky.  The 3.0 tech ref indicates that it can be a .EXE file, but
I don't see how; the segment fixup code is located in COMMAND.COM, not in
IBMBIO.COM or IBMDOS.COM, one of which is responsible for loading drivers
at boot time.  More likely you will have to code it in assembler, or con-
trive a front end for the C.  The new version of Lattice contains instruc-
tions and such for creating .COM programs using C, but remember that device
drivers start at 0, not at 100H.

Goodness.  You'd think this was a real operating system for all the mumbo-
jumbo accompanying the answers to the simplest questions.

Good luck!

-- 
      Dan Frank

	"good news is just life's way of keeping you off balance."