On Sat, 06 Dec 2003 16:54:39 -0800, Alvin Oga wrote: > > > On Sat, 6 Dec 2003, Paul Morgan wrote: > >> IBM did popularize the term "PC", but they sure as heck didn't invent the >> personal computer. And, because they'd bought the rights to the Intel >> 8086, and because of the sheer economic power and brand recognition of >> IBM, we all got stuck with the dreadful Intel segmented memory >> architecture. > > my understanding is that segmented mem like the x86 makes it easy > for context swap and page fault recovery ?? > - 68000 and Z8000 has a harder time to do "recovery" > but easier to write code and faster for general aps > > i like pdp-style apps ... everything directly accessible as memory ... > > c ya > alvin > > - google just had a party at the computer museum .. > - computer museum happen to have all these old toys > ( pdp-8, cray-1, ... all working ... > ( paper tape, catridges, punch cards too
Segmented memory addressing is cheaper, don't need as wide an address bus, and it certainly adds a level of complexity to asm programming, and of course it's slower. I didn't do any asm programming after the 8086/8088, but there was no hardware memory management as you suggest until the 80386. The big downside of that is that all memory was available to all processes; all you had to do was just not play by the OS's rules. I'm digging back in my memory for this, so please read IIRC for every statement :) -- ....................paul "The number of UNIX installations has grown to 10, with more expected." (The UNIX Programmer's Manual, 2nd Edition, June 1972) -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]
