svh@shell.com (Steve V. Hovater) (12/08/88)
I have questions about the way the 8086 processor talks to the Z80
in a Xerox 16/8 (basically, how, and an example would be nice!).
Since Balcones Computer (?) wrote the OS and BIOS, I think it would
be extremely helpful to talk to him/her/them. If they're still around.
Does anyone have an answer to the question, or can point to Balcones?
(Ps.. Still looking for an electronic copy of the Xerox 820-II BIOS).
Thanks...
Steven V. Hovater Shell Oil Company (713) 663-2711
svh%shell.uucp@sun.com
or svh%shell.uucp@rice.edu
or svh@shell.uucp
or ...!{sun,bcm,rice,psuvax1,decwrl,cs.utexas.edu}!shell!svhmlinar@caesar.usc.edu (Mitch Mlinar) (12/23/88)
In article <810@shell.shell.com> svh@shell.UUCP (Steve V. Hovater) writes: >I have questions about the way the 8086 processor talks to the Z80 >in a Xerox 16/8 (basically, how, and an example would be nice!). > >Since Balcones Computer (?) wrote the OS and BIOS, I think it would >be extremely helpful to talk to him/her/them. If they're still around. > >Does anyone have an answer to the question, or can point to Balcones? Balcones Computer only wrote the BIOS and ROM for the 820-II. As far as getting hold of them, good luck. Jim Ferguson (of BigBoard fame among other things) told me many years ago that they wrote the code, collected BIG bucks for it from Xerox, and went away. He did not say whether Balcones existed or not anymore, but it sounds like they are gone. Personally, I have found little use for the 8086 card in the 820-II due to its anemic RAM and so generic MS-DOS that few IBM programs in recent memory run on it. You are better off putting together a clone. On the other hand, I have found a use for the slot to install extra bankable memory that my OS can use. -Mitch
ted@aaifs.uucp (Ted Nolan) (01/05/89)
Ok.. How do you use the slot to get extra bankable memory for CPM? Ted Nolan ted@braggvax.arpa
mlinar@eve.usc.edu (Mitch Mlinar) (01/06/89)
In article <15644@joyce.istc.sri.com> ted@aaifs.UUCP (Ted Nolan) writes: > >Ok.. How do you use the slot to get extra bankable memory for CPM? > The extra slot can has all the Z-80 address lines as well as telling whether it is in the ROM/video bank or in RAM. There is also a nice 32k hole from 4000-BFFF in which to drop a RAM chip (or chips if you have bank selection located there). Of course, you have to have an operating system that can use it. -Mitch