I didn't think of looking at source. I'll dig around thanks for the tip.
Will
On 10/3/20 12:14 PM, Richard Cini via cctalk wrote:
  Regarding #4, if you look at the releases source code
for DOS 2.0 you will see compilation switches for PCD and MSD. I would need to look again
but some were control code things, plus sign-on messages. I know IBM shipped different
tools than MS too.
 
http://www.classiccmp.org/cini
 Long Island S100 User?s Group
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 ________________________________
 From: cctalk <cctalk-bounces at classiccmp.org> on behalf of Chuck Guzis via cctalk
<cctalk at classiccmp.org>
 Sent: Saturday, October 3, 2020 12:44:26 PM
 To: Will Senn via cctalk <cctalk at classiccmp.org>
 Subject: Re: IBM PC-DOS 2.10 explorations
 On 10/3/20 8:38 AM, Will Senn via cctalk wrote:
  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