[Coco] The CoCo Crew Podcast -- Episode 35 is available!

[Salvador Garcia]

 On Wednesday, April 18, 2018, 7:52:40 AM CDT, Rob Rosenbrock <bester at adamswells.com> wrote:
 
 
 <snipped> but details of the BIOS were not released.<snipped>

That is only partially correct, for the later models and definitely true for the PS/2 line, but the early models, PC. XT and possibly AT, IBM included a full listing of the ROM BIOS. This is assuming that this is what you are referring to. There was nomenclature ambiguity (back in those days) because the code in the ROMs was routinely called "ROM BIOS" and the code provided by Microsoft in IO.SYS (or IBMBIO.COM) was called the BIOS. I can say that many fell victim to this confusion<g>.

Have a look here:

http://classiccomputers.info/down/IBM/IBM_PC_5150/IBM_5150_Technical_Reference_6025005_AUG81.pdf


And hop on over to page 194 :-)

Yeah, MCA was a disaster. It came too late, way too late! By that time, the EISA standard was around which allowed a wider bus. There were many (many) PC Clone manufacturers that offered the same functionality as the PS/2 line of MCA computers. Except for the glorious "IBM" brand, MCA was simply irrelevant. The only long lasting contributions made by the PS/2 line of computers was a new video standard (VGA) and new connectors for the keyboard and mouse and even these were quickly adopted by the PC Clone manufacturers.

Salvador