There were a articles in the more technical journal-type mags 1981/82 that discussed porting IBM DOS to non IBM 8088 systems that go into the mechanics of it. DOS v 1.25 was the OEM version for the early ports. *indirectly* from these you might find references to IBM BIOS porting and who did it, there. I have only print copies no scans. Bill
On Tue, Jun 6, 2023, 2:03 AM Chuck Guzis via cctalk <cctalk@classiccmp.org> wrote: > On 6/5/23 22:28, Tom Gardner via cctalk wrote: > > > Can anyone identify a PC-DOS compatible PC announced earlier than > October 1984? Citations would be greatly appreciated. > > That's a tricky one,I think. For example, if a single programmer read > the IBM PC BIOS listing (or even disassembled it) and then wrote a new > one from scratch, that derivative BIOS in the view of the IBM legal > beagles would not have been legal. > > If, on the other hand, the same programmer never saw any of the code, > but read the API description and wrote a BIOS, that would be legal. > > Both ERSO and Phoenix resorted to a "clean room" method where one team > read the PC BIOS and wrote a description, which served as a > specification for a derivative BIOS. I think that the descriptions were > cleaned up a bit and published as the Phoenix BIOS books. > > But I think the first "clean room BIOS" was in the Columbia MPC-1600, > June 1982. > > --Chuck > > >