garyh@iddic.UUCP (Gary Hanson) (11/21/84)
Here's some books for the Christmas lists of 1541 hackers or would-be 1541
hackers:
First, a hardware book, the '1541 Maintenance Manual' distributed by
GOSUB of Slidell, in Slidell LA. (they advertise all the time in Compute
Gazette). This is a quite thorough reverse-engineering job on the 1541
hardware, including theory of operation, block diagrams, troubleshooting,
alignment instructions, and complete schematics, parts lists and component
layouts for both the long and short board models of the 1541. It costs
about $30, and may be worth it if you ever have to fix your 1541, or if you
just want to mess around with its innards. I have a few minor quibbles with
some of its suggested preventative maintenance routines; in general
(especially with the 1541), if it ain't broke, don't fix it.
Next, a software book: 'Inside Commodore DOS' published by Reston Publish-
ing, also bearing the Datamost logo, available at bookstores; try B Dalton
if there's one near you. This book virtually blows the Abacus 'Inside the
1541' out of the water. They deal extensively with how to run your own
programs inside the 1541. They include lots of ready-to-type in programs
for creating various disk errors, disk utilities and suchlike. They discuss
in detail the exact disk format, GCR encoding, various (generic) copy-
protection schemes, error messages, and more. There's very little about
how to use the drive from a user's standpoint (as Abacus has, at great
length), but a wealth of information for hackers. It also includes a COMPLETE
memory map for the RAM, and descriptions of all major (and even minor) entry
points in the firmware. It does not include a complete disassembly (as Abacus
does), but they provide much more information about what's going on in the
firmware and how it works. There are some obvious typos in the book, and
a discussion of firmware bugs that I'm not quite sure really exist, but if
you are at all interested in how the firmware works, get this book. Then,
look over the Abacus book, and buy it if you think you need it too. If you've
already got the Abacus book, get this one too, anyway. There is so much
detail on the firmware, it looks suspiciously like they were working from
a copy of the original source listing of the DOS (rumor has it that there's
copies of the listings circulating in the 'underground'). An excellent book,
costing about $20.
Gary Hanson {just about any biggie}!tektronix!iddic!garyh
>I don't want a computer to be my friend, I want it to be my SLAVE<