At 21:16 12/01/2003, you wrote:
> > Part 1:
>
>[...]
>
> >
> > So: 5pm, trip to Maplins to get the components. "Sorry guvnor, no
> diodes in
> > stock". OK - fall back to the plain X1541 then; at least it'll work on my
>
>That figures... Maplin rarely have useful components in stock in the
>shops any more. They were out of stock of 10k resistors one time I needed
>them.
They seem to have really gone downhill in the last few years; I suspect the
passing of Tandy has something to do with this - why should they care,
there is no national competition. :(
> > again, the traffic jam was horrendus, so glad I didn't. Arrived home,
> found
> > most of my soldering gear, except the tin of excellent tip cleaner/tinner.
>
>I am trying to work out why your soldering iron was not on your bench
>where it should have been. Unless you had taken it somewhere for a field
>repair, of course.
Sad to say, I don't do anything like enough electronic
assembly/disassembly. This is only the second time I've used the iron since
I moved here over a year ago. Plus the fact that anything which could be
described as a bench is currently fully occupied with computers and/or
peripherals of some description...
I still haven't fixed up that 8032 yet (it lurks in the cupboard awaiting
my attention), and I've got a project 3032 as well now - this is the one
which started up stuck in the monitor routine the other day, but when I
tried it again this morning the screen is just blank. I know the video side
is OK, as if you let the tube warm up, then power cycle it, you get the
garbage characters for a second or so, then it clears to blank. I've
re-seated all of the smaller chips to no avail; will try the big chips
tomorrow, after that it's a crash-course in microelectronic diagnosis.
Indefinitely postponed, knowing me.
> > Nevermind, tip's still clean enough. Apply vice to desk, start soldering
> > 6-pin DIN. Amazingly, I didn't completely wreck it (although some of the
> > pins needed realigning afterwards). *Surely* there's an easier way??
>
>Sticking the pin-bit into a 6 pin DIN socket helps a little. Using a good
>soldering iron also helps. But I agree, DIN plugs are painful to wire,
>and mini-DIN plugs even more so.
Hmmm. I actually had less trouble with this one than I've had in the past,
possibly because the solder actually stuck to the pins this time. Mostly
the pins seem to gather crud like there's no tomorrow, then the solder
won't grip, and you end up melting a pin right through the plastic. Grr. I
mean, all they have to do is make the plastic bit out of bakalite - problem
solved.
> >
> > First, I try the disk in an 8050: No joy. So, back downstairs, pick up the
>
>One of the most stupid design decisions in the CBM drives was that the
>8050 was not even read-compatible with the older, 40 track, drives like
>the 4040.
Agreed.
> > Open 3040 up, it looks like an electrolytic cap has burned out (literally,
>
>It's normally tantalum (electrolytic) capacitors that do this. I've had
>many of those explode...
Hmm. It's presently unidentifiable (just a black smear on the circuit
board). I'll stick a photo up soon, and hopefully someone with a 3040 can
identify the component for me for replacement.
Thing is, did the tantalum cap blow because it was old, or because
something else was awry?
>place. I cleaned the heads. Worked fine, and still works. So you might
>want to clean the heads on the 4040...
Good point. It was one of the things on the list, but has been postponed
following actually getting it working.
> > 1) Is it actually possible to copy files from one unit (i.e. diskdrive) to
> > another (i.e. Shark)? The COPY command can't (it even says so in the
>
>As I meationed eaelier, the COPY command really runs on the processor in
>the disk unit (the Commodore floppy drive units contain 2 6502s, one to
>run the DOS and handle the IEEE-488 port, the other to actually handle
>getting bytes to/from the disk [They communicate via a shared memory
>area, one of the features of the 6502 is that you can clock 2 of them
>together, one with an iverted version of the clock, and they will happily
>interleave accesses to memory]. This means that the COPY command can only
>copy between drives in the same disk unit.
Yes, I'd guessed that was why. It's a shame (but, nevertheless,
understandable why) Commodore didn't implement routines to allow unit-unit
copying. However, when hard-disks are concerned, I'd have thought it was
essential to be able to copy to/from floppy unit to HDD unit. Maybe someone
with a 9060 drive (or the other one, who's number I forget) could see if
there's any CBM utility to copy files? If so, any chance of a copy of it?
>I guess there must have been programs that read a file from one disk into
>the PET's memory, and then write it out again to another disk (possibly
>in a different unit).
I would assume so. I've not really gone looking for one yet, but will do.
--
Cheers, Ade.
Be where it's at, B-Racing!
http://b-racing.com
Received on Sun Jan 12 2003 - 16:54:00 GMT