On Wed, 6 Aug 2003, Fargusson.Alan wrote: > I agree that IBM should have used the Z8000. However, I know that Zilog could not > have produced enough working chips. In the 1981-1982 period we had a hard time > getting enough working chips for our own internal use. The ones we got were much > faster than the 8086 though. Our Zeus (Unix) systems made MS-DOS on a PC look slow. > OTOH even our Z80 system was faster then a PC. I think we were making 6MHz Z80s in > 1981. I think our Z8000s were 6MHz or 8MHz.
I presume "we" == 'Zilog." Maybe Intel would have helped you out;-) I know they also made the Z8530, another part I think should have been in the PC. And the DMA part;-) I had the docs on most of the Z80 family: there was a DMA controller that connected to the bus, not a part and (as I recall) could do DMA between any two of memory & I/O device. The Z80-SIO capable sync, async and HDLC. The 8530 is (you can still get them new) the Z8000 version. I don't recall much about the Z80-PIO. All the Z80 family devices daisy-changed for interrupt handling, you didn't need a PIC like Intel's -- Cheers John. Join the "Linux Support by Small Businesses" list at http://mail.computerdatasafe.com.au/mailman/listinfo/lssb Copyright John Summerfield. Reproduction prohibited.
