Compupro Disk Images Uploaded

Fred Cisin cisin at
Sat Oct 29 23:06:16 CDT 2016

>> Simplest test for MS-DOS 1.25 would the the dates of the files, 
>> particularly IO.SYS and MSDOS.SYS.  IIRC, 1.25 would be in 1982, maybe 
>> June.
On Sat, 29 Oct 2016, Chuck Guzis wrote:
> 1.25 was licensed for OEM customization for quite some time, so dates
> could well be later, depending on the OEM.

Very true.
When was the earliest that a 1.25 was released to OEMs?

On the other end, 2.00 came out somewhere around march or April 1983.

If the dates are in the right range, then there are other clues, such as 
matching file sizes.

Starting with 2.00? there was a version number buried in the code, and the 
VER command would print some text, and then calculate what to display for 
the numbers (major version, period, minor version as a 2 digit decimal 
number.0 (19h gave .25)
But, if 1.25 didn't have that, then somewhere in COMMAND.COM, there might 
be text saying "MS-DOS 1.25", instead of the later ""MS-DOS ", to be 
followed by calculated values.
Did 1.25 have ANSI.SYS and CONFIG.SYS?

For somebody who remembers the detaails of the transition, many of the 
text messages in COMMAND.COM might be recognizable.

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