16 Mar
2000
16 Mar
'00
7:04 a.m.
Hi,
Interesting, I always wondered why they had moved away from the IEEE bus.
I'd always assumed they'd done it in an attempt to reduce costs (those IEEE
cables weren't cheap) and to try and lock users into using CBM peripherals.
>...."serial" bus is actually a bastardised implementation
>>of the IEEE-488 bus, which CBM had used on the PET series.
Caused, IIRC, by Tramiel who demanded of the engineers that
the next computer not use the same connectors because of a
supplier shortage.... There's a great book on the PET and its
implementation of the
IEEE-488 bus by Osborne Press. If you ever see a copy of it at
a bookstore or flea market and have even considered programming
for the PET, grab it.
I *THINK* I've got that book (came with one of my PETs). I can't remember
the title now ("PET IEEE Interfacing"?), but it goes into a lot of detail on
how the bus works and includes several practical examples.
Hang on....goes off to have a rummage....dammit, can't get at it right now.
:-(
It was because of this slowness that at one company,
Software
Productions, we compressed the menu and splash screens for our
C-64 version of "Micro Mother Goose" (sold under the Reader's
Digest label). It was a simple RLE compression, but it cut the
pictures down about 70%....
Yes, I did some work for a local company called "Novagen" back in '85 which
was pretty similar.
In this case we were putting the Atari 8-bit version of "Mercenary" onto
cassette and wanted to display a logo screen while the game was loading. I
wrote a very simple RLE compression program to allow us to load the screen
in a reasonable amount of time....there was an awful lot of green in my logo
so it compressed VERY well. :-))
That was the first time I made any money from programming.
TTFN - Pete.
--
Hardware & Software Engineer. Sound Engineer.
Collector of Arcade Machines, Games Consoles & Obsolete Computers (esp DEC)
peter.pachla(a)wintermute.org.uk | www.wintermute.org.uk
--