TRS-80 Model 1 vs Model III disk/application compatibility question
ard at p850ug1.demon.co.uk
Tue Jan 27 13:14:14 CST 2009
> Hi, all,
> I was cleaning up around the house and wanted to stash a Model 3 on
> the shelf out of the way. Before I did, I fired it up to make sure it
> (still) worked, and to try something I haven't tried before...
> I have diskettes, c. 1982, from a friend lying around, so I booted it
> into TRSDOS 1.3. All seems well. It claims to have 48K (internally
> and according to the markings of the case and the memory report at
> boot time), passes MEMTEST (which is on most/all of the TRSDOS disks),
> it runs BASIC, and it starts a couple of binary games I found. What
> it does not do is run Zork or Enchanter.
> I have original Zork I and Enchanter disks. Booting up a backup of
> the Zork disk gets me to a TRSDOS prompt. I can take a DIR and see
> the program and the data file there. If I start Zork, the screen
> blanks, the disk gronks and the access light blinks occasionally. I
> hear what sounds like successive track seeks (which I'm expecting
> since I know how Z-Machines work and roughly what virtual pages need
> to be loaded to get a game started), but then after a few seconds
> (less than 2 min), it sounds and looks like it's in a loop and repeats
> the gronking and flashing. I never see anything on the screen except
> for a blinking cursor. The Enchanter disk isn't much better - I think
> it spins the disk and gronks for a bit, then goes quiet.
> I'm posting because I am reasonably certain, due to age if nothing
> else, that these are Model 1 diskettes. Enchanter is a flippy, with
As far as I rememebr, a Model 3 will not boot any Model 1 disk (or of
course vice versa). There have been disks that were made to boot on both
machines, by having a mixture of single and double density sectors on the
boot cylinder IIRC, but no nornmal OS will boot that way.
So the fact that the disks boot to a TRS-DOS prompt implies they're M3 disks.
I have Zork 1 for my Model 1. It was a self-booting disk, no TRS-DOS or
similar. And it was copy-protected (nothing that SuperUtility couldn't
manage :-)). So again, it sounds like you have a Model 3 version,
Since the system will boot other disks and run other programs, I susepct
either an unreadable sector on these games disks or something marginal in
the disk drive or disk controller.
Have you tried to make a ackup of Zork and/or Enchanter? If so, do the
backups behave inthe same way?
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