Zenith Z90

From: Jeff Kaneko <Jeff.Kaneko_at_ifrsys.com>
Date: Thu May 7 09:21:02 1998

> OK, the manual says 'Micronex Pixelplotter Graphics on the Z89/RFI
> computer'. It also says 'Micronex Limited, Harford Square, Chew Magna,
> Bristol, England'. I've got the installation instructions and memory maps
> - the thing contains 16K of RAM which is bank-switched with 16K of the
> normal memory. I think my board uses port F2H, bit 3 to select the new
> 16K, but I'm not absolutely sure. More info when I pull it apart....

To the archives, then. Lets see what we can dredge up . . . .

> Please do. Copying them could be a problem as they're pretty large
> sheets, but even being able to check details with somebody when I'm
> tracing things would be useful.

Found the print! My company has a blueprint copier, so I can
re-produce it, no problemo.

> I do have an external Zenith disk unit, but it contains 2 Siemens drives
> that are identical to the one in the Z90. I assume they're 40 track.

Ah, ok, yes, 40 track. Hm. Usually if they went to the expense of
external drives, they either went all the way with 'em or just added
a drive to the Hard-sectored controller (like a friend of mine
originally did).

You also had these jaded individuals who used the Z-67 8" controller
card, 8" floppies, with a winchester. These guys really had money to
burn. Sheesh.

> Yes, that's mentioned in my hardware manual. I assume, though that I can
> use the strobe disk on the spindle and set it like any other 300 rpm
> drive. I will probably check the speed (and the head alignment - I have
> the disks to do that) before I do anything serious with the machine.

Alignment disks, eh? Boy those are getting scarce (not to mention
even more costly than ever before). I tried lighting up my H-89 last
nite (to my wife's dismay).

My 89's as dead as a doornail-- only one 'beep'. Damn. More
hardware I gotta fix now. First, I have to find all of the original
PLA's and proms and stuff that were installed *before* I added the DD
controller, which will be a project in itself. :-/

-- Jeff
Received on Thu May 07 1998 - 09:21:02 BST