On 09-May-99, Doug Coward wrote:
Doug Spence wrote:
> Does anyone have the program "RACE" from Cursor #2?
About a year ago, I transfered the first 15 or so
CURSOR
tapes to Commodore disk for Larry Anderson to put up on
his BBS.
Hey, thanks! I don't know how long it's been since I visited his web
site (I even have a link to it on mine) but I don't remember all those
disk images being there before.
The "RACE" program from CURSOR #2 is on the petgms08.d64 archive.
This is actually the file I was trying to salvage with the sound
sampler. I'm glad I don't have to do that now, but I'm still interested
in the format.
BTW, I collected all twelve of those PET disks from Larry Anderson's
site, but I haven't transferred any of it to the PET yet. I've looked
at "RACE" on one of my C64 emulators, though, and it has "CURSOR #2, AUG
1978" as the remark on the first line, so I know it's the right one.
I'm eager to check out some of the machine code games.
If I can find the tape, I can transfer it to
the pc on the little C64 dev station I set up at work.
Wow! I guess you really MUST be the senior software engineer to have a
C64 dev station at work. :) (Not a comment on age, a comment on being
allowed to have cool toys at work.)
Doug Spence wrote:
>I need some information about the Commodore cassette storage format.
>....snip.....
>In the data portions, it appears as if every 20th wave is special
About a year and a half ago, I took my shot at
converting wave files.
Unfortunately I had to move on to other projects just as I was making
progress.
First, IMHO if you are sampling at less than 44.1, you are making
things too hard on yourself.
I'm limited to 40K, and I can't play samples at that rate unless I
change my screen mode. The sampler and software are Classic, and the
computer I'm using them on will be next year. The software only allows
sampling to memory, so I wanted to keep things small.
25.5K doesn't seem too bad, but after reading the rest of your
description and the sample output from your program, maybe it *isn't*
good enough. The differences between the short and long pulses aren't
very big. You're using 15 samples as your cutoff between short and
long, and I see that 14, 15 and 16 appear. That's shaving it pretty
close!
With that information, I determine the byte like this:
* the first two pulses are 1 and 1 - this is the sync bit.
* the next two pulses are the low order bit
* a 1 followed by a 0 is a 1
* a 0 followed by a 1 is a 0
* and the last two pulses is the parity bit
That's pretty darn cool.
Thanks!
--
Doug Spence
ds_spenc(a)alcor.concordia.ca
http://alcor.concordia.ca/~ds_spenc/