4 Oct
2020
4 Oct
'20
7:44 a.m.
On 10/3/20 11:44 AM, Chuck Guzis via cctalk wrote:
On 10/3/20 8:38 AM, Will Senn via cctalk wrote:
Thanks Chuck, I didn't know about vcfed. I'll head over there. Your
points about display memory is helpful, as is the rest of your post. I
appreciate it.
will
Some questions I have related to the exploration:
1. I'm curious if there are other folks out there doing similar stuff?
2. Most of the Assembly examples use DOS interrupt 21 for output. Is
this typical of assembly programs of the time, or did folks use other
methods?
3. I was able to find a lot of 5150/5160 and other manuals, but I
couldn't find an IBM Macro Assembler 2.0 manual (there are plenty of IBM
Macro Assembler/2 manuals, but those are for OS/2, not DOS). Does anyone
know where I can find one online?
4. In y'all's view, what are the significant differences between IBM
PC-DOS 2.10 and it's brother MS-DOS 2.x?
5. I'm thinking of moving on to 3.3 at some point, in your view, what
are the advantages?
6. I'm happy to post here, but if y'all know of a more appropriate
venue, please suggest it?
1 and 6:The folks at vcfed.org are far more involved
into things PC; I
would recommend that venue.
2. Interrupt 21 is the most hardware-independent way to perform console
output. It is neither the fastest nor most flexible. Most MSDOS
programs needing fast or full-screen control revert to writing into
display memory directly, which is a bit more involved, but worth the
effort. There are also INT 10h calls, but again, for text output, they
can be very slow.
3. Can't address that one--I have 1.0 and 4.0 and later in my library;
I'm not sure if I have the "gap" ones. MASM 1.0 was a huge mess; the
product really didn't start to mature until 4.0.
4. MS-DOS 2.x had numerous variations, such as that employed for the
NEC PC98 series of machines, as well as numerous other non-IBM PC
platforms. As far as I know, PC-DOS was configured only to be
compatible with IBM's own product line.
5. 3.3 was very popular in the day; one thing that it provided was a way
to avoid some of the storage limitations of earlier versions. It also
introduced quite a number of API additions (see Ralf Brown's interrupt
list for details).
--Chuck