💾 Archived View for mirrors.apple2.org.za › archive › www.textfiles.com › apple › acatprogram.txt captured on 2023-11-04 at 16:06:29.
⬅️ Previous capture (2023-03-20)
-=-=-=-=-=-=-
Advanced Programming Information Fixed
--------------------------------------
30-MAR-85 By Homer Brothers Software
Please upload this doc on every bbs
you use so that everyone will start
programming your Cat correctly.
Along time ago when the Novation Apple
Cat was first released, Novation
thought that they would be nice people
and give all you hackers information
on how to diddle with there hardware.
Well since that time many of us have
found that they messed up in a few
places, in fact, Advanced Programming
Information has more bugs than
COM-WARE did. To my knowledge the
API manual has never been de-bugged.
So please throw away your programming
ego for a few minutes and take the
time to read this file.
Thanks
Homer Brothers
P.S. I never want to see another 212
card turn on unless it was suppose to!
--------------------------------------
The most important bug in the API
manual is the 212 card bug. Please
turn to page 7 students. If you will
notice the SQUBYT register's hi order
bit is the 212 disable/enable bit.
Yes dreaded ol' bit number 7 must be
on to disable the 212 card just like
it says here. That means to have the
handset squelched the cassette off
and the 212 card off, you would need
to store a $81 in SQUBYT. Now your
saying well thats not a bug in the
manual, well your correct, that
actual bug that has confused so many
is on another page. Please turn to
page 24 students. Please notice the
modem INIT routine where they load
the accum with binary 00000001, a hex
01... Right about now your saying
damn I shouldn't have cluged that code
I knew it sucked the second I looked
at it. Well give him a break, he wrote
this thing probably before the 212
card was finished.
Ok class, you have learned of the most
common error in programming the Cat.
Well now, if all you stud programmers
have managed to stay with us, let me
please point out some of the more
obscure mistakes in programming the
cat. (Ones even total stud programmers
have made)
Please turn to page 15 students. Ah
yes, the dreaded XMTBYT. The cause of
so many early apple-cat repairs. Yes
believe it or not, many programmers
never bother to shut off the carrier
when they hang up the phone line (As
the micron did in his Catsend bbs).
Leaving on the carrier after hanging
up the phone is not good for the poor
little heat sensitive LSI chips that
Novation designed, so you can only
add to the life of them by giving the
carrier a rest after the caller is
logged of by powering there bod's
down. That means a $1F to the XMTBYT
and a extended life time for the Cat.
Ok, well so what that wasn't a bug in
the manual heres another for you.
Please turn to page 4 students. Ah yes
the much loved SWBYT. This do all
register has been so misunderstood
because of the mistakes in API.
Ah those lovely firmware switches,
when used with the firmware protocol
they can tell you your modem defaults,
ie 212 installed? Welp as you may have
already noticed they botched the bit
order on the switches. The register
should read-
SWBYT
7 6 5 4 3 2 1 0
DV BSR CD AD SW3 SW2 SW1 SW4
Ok well you thought I would never find
more than one bug... So whats next?
Well students flip to page 21. On the
bottom of the page you should see the
Label CHKRNG, as you can see they check
ACBYT's ring bit. If the phone is
ringing, they print a nice little
message and wait for the line to stop
ringing. Now if your saying, well
thats stupid, why don't they just
pickup the phone?, well that would be
okay with most modems. BUT! Novation
botched the hardware on the Cat, and
if you pick up the line while the 55
volt ring pulse is there, WHAM! the
cat takes a jolt that nocks its
registers silly.
Well by now your saying, thats it,
nothing else... Well I am not out of
breath yet.
Bad programmers (shame on you) do
somthing like this when they init
there hardware.
INIT SEI
LDY SLOT
LDA #%10000001
STA .... etc etc etc
init init init....
RTS
More experienced programmers (I love
you guys) do somthing like this.
INIT PHP
SEI
LDY SLOT
LDA #%10000001
STA .... etc etc etc
init init init....
PLP
RTS
Hey, he knows that other devices use
interupts besides the CAT... boy that
guy must use ProDOS.
Well thats realy about all the bad
things I can say right now. I will try
to come up with some more. Please take
the time to make sure you understand
what I did here if you plan on
programming your cat from 6502 machine
code, then rip it up and say you knew
that a lot longer than Homer did.
Boy don't we programmers have big
easily dented ego's? I know I do.
OH! I cant end this file without
saying this.
REAL MEN USE EDASM ProDOS! Boys play
with Merlin and its wimpy little
symbol tables. Oh yeah and,
REAL MEN USE A DCI BASED PRINT
Whats that? This-