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(This article was first published in the ICPUG
Journal MARCH/APRIL 1989 issue.
Permission from Joe Griffin to republish on the Internet has been
received.)
Good Grief, Commodore, NOT AGAIN!
The opinions and comments contained in this article are my own and do not
constitute an official statement in my capacity as ViceChairman of ICPUG.
The findings are based on my experiences with my own 128-DCR (metal cased
machine) and a friend's 'Portable' (plastic cased model). The latter
machine has been used with both the 'as-fitted' (Version 3) ROM and a
'Fix-ft' (Version 5) ROM.
I would welcome feedback from other owners of the metal
cased machine, particularly from any American users.
Back in the summer I bought a C-128, to take over from the PET as my main
workhorse. After some consideration, I decided to buy a new 'Desktop'
model for four main reasons.
1 Better shielding (less radio interference)
2 No fan (quieter)
3 64k video RAM (allowing more intricate screen usage)
4 latest disk ROM (fixing the dreaded 1571 bugs)
At least that's what I thought. After an initial pedod of teething trouble
during which a Video RAM fault appeared, I sent the machine back for repair
twice. The first time it was returned to me, there was no change in the
fault. The second time it came back, the fault was fixed but after half an
hour, an I/0 chip blew and it got very fussy about accepting anything from
the keyboard. At that point I was given a new machine! Touch wood, it's
still working.
At last, I was able to compare the results obtained with my
requirements. Unlike my PET which made any radio within 50 feet howl, the
C-128 gave only minimal interference. It does exhibit a slight hum from the
power supply, but compared with earlier 128D's, it's virtually silent. I'm
just starting to get into Video, but the extra ram does appear to be useful
for things like a 48 kbyte ramdisk. Finally the 1571 seemed to be a good
fast drive and as it would happily compile a large program with PetSpeed, I
assumed it was bugfixed (an earlier 1571 fell over In a fairly spectacular
fashion until a 'fix-ROM' was fitted). I transferred a large, important
database from the 8250 to the 1571 and was pleased by the general
behaviour. Time passed and I used and altered the data, taking regular
backups.
Then I heard that Superbase 3 was nearing the beta-test stage. I rang Peter
Maclaurin of Precision to offer my services, explaining that I had a new
128D, so I would be able to check its behaviour with the fixed ROM. My
complacency was somewhat rudely shattered when Pete asked "Why do you say
R's got the fixed ROM, have you put a new ROM in?" I explained that it was
a new machine and therefore... Pete interrupted me and explained the simple
fact that just because Commodore have fixed the ROM doesn't mean that they
actually put it into their computersI He advised that I use the Greg Perry
program to check it (see ICPUG National Magazine Vol 9 No 3, p 239).
That evening, I typed in the few lines of Greg's program
and set it to work. It chuntered away, creating a large relative file and
writing a few records. Then it continued, apparently reading from the
relative file and writing into a sequential file. This was fine, obviously
there were no bugs in this drive! Then came the point at which the write
file was closed and re-opened for reading. Up came the message 'write file
open error'. Well at least it wasn't the original bug! After some time
experimenting, I found that it left the sequential file as a 'splat' file,
rather than a correctly closed one. So much for a bug-free drive.
At that point I started to look at my database and found
widespread corruption. Fortunately my earliest backup (of 4) was only
suffering from major damage, not total disaster. Using the Superbase
Utility program I was able to get back all but 5 records and I was able to
copy those across from the 8250 version.
After talking to both Precision and Commodore at the PC
Show, I opened the 128D and checked the ROM number - it is 318047-01 (DOS
$62A0). 1 was told that it is actually version 4a, a partially fixed, stop
gap version. The theory I was given for its existence is that if Commodore
actually released the ROM, it would be seen as an acknowledgement that
earlier versions were wrong and the door would be open for all kinds of law
suits.
After some delay, I obtained a version 5 ROM (Part No
310654-05). This was fitted and checked. The test program behaved correctly
and soon everything seemed OK...
A little time later, I tried to back up one of my work
disks, using 'Gulp Copy' a utility (from Transactor) which uses the 1750
RAM Pack to buffer an entire disk. It hung!. Well, I thought, some of the
routines have moved around a bit and there isn't a lot I can do about it
until I have time to look at the code.
Some considerable time later I bought 'Big Blue Reader'. It
worked well on the 1581 but hung on the 1571. The manual did advise
upgrading to. Version 5 roms, so it couldn't be that. I quickly checked
this by running it on a friend's 128 (with Version 5 ROM). It worked
happily. A copy of the ROM code was taken from each machine and compared -
they were identical!
What I had overlooked is that the latest 128D's (referred to as 128-DCR)
are the 'cost reduced' version. I believe that there is also a 1571-CR. In
my 'D' there is no separate disk controller board, just a single
motherboard. Most importantly, the drive does not include the Western
Digital 1770 controller, which handles the burst mode activity. I suspect
that my problem was that the ROM was trying to use burst mode with a
controller which was not there. Discussions with one source have suggested
that the 318047-01 ROM is essentially version 8 of the 1571 ROM and that
this will be offered in future, in place of version 5 as an upgrade.
From my findings, it appears that we are right back to
stage one with the 1571 bug. Until such time as Commodore can offer us a
working fix, any 1571 drive using the 318047-01 ROM should be regarded as
suspect and not used a a double sided drive when important data is at
stake. If in doubt, use the Greg Perry program to check out your
drive.
As I stated at the start of this article, I would welcome feedback from
other users, just in case I have a 'rogue' machine. In the meantime I am
contacting Commodore for their comments. I will report progress through
this journal.
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