motteler@umbc3.UMBC.EDU (Howard E. Motteler) (01/03/90)
In article <2665@umbc3.UMBC.EDU> alex@umbc3.umbc.edu.UMBC.EDU (Alex S. Crain) writes: >In article <29@suntau.UUCP> forrie@suntau.UUCP (Forrie Aldrich) writes: >>This may sound a bit foolish... so bear with me: >> >>If you can 'boot' the unix-pc from a floppy... I wonder if there is some >>way to use this machine with another type of opsys than unix... like to >>have something else on the floppy to load into the processor... do you know >>what I mean? > [ basic discussion of loaders ] > You could write something else, but that falls under >the topic of kernel programming (in a big way) which is beyond the scope of >this posting. > There is an interesting issue of Micro Corncopia (march/april '89) where Karl Lunt does just this (and then some) but for a Convergent miniframe, an earlier Convergent product with many features in common with their S/50 (aka 7300 aka Unix-PC). Anyway, Lunt picked up a 512 K miniframe (just the board) very cheap on the surplus market. To quote from the article: "But this card wanted to boot and run Unix--I wanted to rewrite the code in the EPROMS to do something more interesting. [!!] This meant figuring out where all the peripheral chips, EPROMS, and RAM resided in the CPU's 16 MB address space." The story on how he did this makes a very interesting article. He starts out with ZERO documentation. He dissasembles the EPROMS, and eventually wrote his own simple monitor, after several stages of "test" EPROMS. The end result was that he had it running "SK DOS," which is a sort of MS DOS for 68000 based machines. At first I thought this was a pretty strange thing to want to do, but given how slow unix runs on a 1/2 meg machine, maybe it's not such a bad idea after all! -- Howard E. Motteler | Dept. of Computer Science motteler@umbc3.umbc.edu | UMBC, Catonsville, MD 21228