He shoots! He Boots! Heath Lives!

From: Stacy C. Morang <smorang_at_enm.maine.edu>
Date: Mon Jul 14 11:54:24 1997

Roger Merchberger wrote:
> Whilst in a self-induced trance, Stacy C. Morang happened to blather:
> >On Tue, 24 Jun 1997, Roger Merchberger wrote:
> You're right, but they seem to format to only 320K (8 sectors/track, not 9)
> with the DOS I do have, which is listed in the stats of the machine I
> listed below...

If you give the format program a '/9' parameter you get nine sectors, at
in dos 2.
> >Top, I think. (I have one, but I only got it for the Winchester drive
> >card).
> Whaddya did with the rest? A few spare parts might be nice (or a color
> tube, if yours had it... ;-)

No color tube (you can activate color on the video card with 18 64K (or
32K) memory chips (4164, I believe)) - I might be able to help with
some things, however
I am keeping the machine as a backup / parts for my Low-profile unit (I
one to make 8" formatted disks).

> > I don't doubt your memory, but I think this is a (prolly earlier) version
> of the monitor rom... specs to follow. I fat-fingered *all* the keys on it,
> and here's what works:
> B -- boots. Accepts parameters of: 0, 1, 2, 3, and that tells it what
> floppy to boot from. Plain B assumes floppy 0, which is top. Thanks! All
> else beeps with invalid parameter, except "S", which appears to do nothing.
> Would this be boot from the serial port, perchance?
> V -- Version of the monitor rom, which is Version 1.02.
> Nothing else worked...

I think the version I have is 1.05, but I'm just guessing.

> Questions:
> 2. How high can this rascal go in memory? I located 3 banks (9 each --
> parity) of 64kx1 300ns DRAM, two of which are populated. Mathmatically,
> that works to: 128K RAM. The third bank is empty. Can I pop in 9 more chips
> without setting any jumpers/dipswitches? How about bigger DRAMS? (prolly
> not... but it's worth an ask!) Still, 192K is still pretty good for a
> machine from '82!

Yes, you can add 64K DRAMS - the heath versions came with 128K, the
Zenith (for business use, presumably) came with 192.

If you change a couple of the PALs, and depending on how on how old it
is, maybe something else, you probably can put 256K DRAMS in it. There
are several documents that talk about such modifications, look in
SIMTEL-20 archives, among others.

> (also, on the question of jumpers... anyone have a tech-like manual for
> this thing I could get a copy of... or at least a copy of the important
> pages?)

I have most, if not all of the technical stuff, I'll have to dig it out
as it is
packed away, so don't let me forget.

> 3. The video board which is based on the Motorola 68A45P video chip,
> presently has 64K onboard for *just* the green section of the board.

The chips may be 32K parts (64k parts with one half dead).

> rascal can handle 192K Video Memory!!! Funky! ;^> (that is, if I'm reading
> the boards right.... but CHKDSK doesn't return the added video memory, so
> that'd seem correct.) Does the board support any form of graphics? I tried
> the standard basic commands (ZBasic was on the floppy) but it seemed only
> to work in text.

Yes, it does handle graphics, (you can get 640x400 out of it with out
too much difficulty). I don't remember how ZBasic, which is not the same
as GW-BASIC or BASICA, makes graphics.

> Well folks, I havta say: This is one *sweet* machine! :-)

It is much more sophisticated and capable than the IBM-PC, but was
marketed rather poorly. I still have a review on it somewhere.

> >I'm not sure what the licensing requirements are, however, I do have
> >several OS's for the machine - I'm sure something can be worked out.
> Did Heath/Zenith bundle an OS with the disk systems? If so, wouldn't I own
> a license to own a copy of the included OS, as I own the machine? I'm not
> sure how stuff like that works, especially on the old stuff.

Nope. That was separate, as you had choices. I doubt anyone is too keen
on suing over a copy of Z-Dos 1.25, (or the P-system for that matter),
but it would be wise to try to see if anyone cares.

Stacy C. Morang, Communications Specialist
Education Network of Maine
scm_at_access.enm.maine.edu, smorang_at_enm.maine.edu 
So long, and keep your stick on the ice.
Received on Mon Jul 14 1997 - 11:54:24 BST

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