18 Sep
2014
18 Sep
'14
5:15 p.m.
On Thu, 18 Sep 2014, Ali wrote:
Fred,
So would a program written for Microsoft/IBM (just to be clear) DOS work on
the 8" DOS distributions? I.E. was the only difference the medium of
distribution (a la 3.5" vs. 5.25")?
IFF it were written to be fully MS-DOS compatible, then it should work on
just about anything running MS-DOS.
BUT, few things were. Programs written for PC&Compatibles generally
assumed that other things besides the DOS were the same. For example,
MS-DOS can write a character to the current cursor position. BUT, in
order to get more speed, many/most programs shoved the characters into the
screen memory, instead; that prevented them from running on anything with
different video hardware.
I know DOS had support for 8" drives
through 6.22 (see MS KB 75131). The reason I ask is because then one could
theoretically use DOS based imagers/zip utilities/etc. for copying 8" disks
Depends on what you mean by "imagers". Programs that deal with disks with
other sector sizes are going to bypass DOS and talk to the BIOS, or talk
directly to the FDC hardware.
if you have a system like the NEC one (I assume it is
PC compatible since it
runs MS-DOS).
No, that makes it MS-DOS compatible, NOT PC compatible. "PC compatible"
is a subset of "MS-DOS compatible" that also has the same video, floppy,
etc. hardware.
I haven't ever heard of anyone doing this so I am
sure I am
missing something. The other option would be some of the turn key systems
you alluded to (i.e. ISA controller card with external drives) but finding
one now would be very hard to do. Everything else I've read about
copying/imaging 8" disks make it sound rather complicated.
It's not necessarily THAT complicated. Just by cabling an external drive
to an ordinary PC's 1.2M compatible controller will provide the hardware
necessary to be able to deal with most MFM ("double density") 8" disks.
Single density adds some more fun and games.
--
Grumpy Ol' Fred cisin at xenosoft.com