Re: Tape85


[Prev][Next][Index][Thread]

Re: Tape85



Just wondering.. What grade are you in? :-).

If I say kindergarten, I bet i'm close. What's so hard to understand
heres.. I said a load of times you are going to use a plain old walkman,
and last time I checked they still take 'regular' tapes. ie: the ones you
buy and put in your plain old tapedeck and then hit 'play' on. As to am I
goign to build them, I just said a lot of times that I don't have much
experience with ADCs, which is a hardware (something physical.. like you
would solder it and attach a few wires and connect some kind of
powersupply...), and therefore either someone else picks up the idea and
builds a suitable ADC (this should be really simple), or I find something
suitable on the inet and a good info source on implementing ADCs. (or get
my hands on something right now without having to shell out a lotta money
or taking something valuable apart.) Maybe i'll find an old soundcard
somewhere and they have ADCs.. the memory capacity depends on the size of
the tape, and the quality. If it's high quality (Type IV is high, II is
medium, and I is low.. quality goes down as you use tapes more. ie: if you
record over your type II tape for the 5th time, recording over a brand new
never-used type I tape will probably end up better quality..). The driver
can record with less error-checks and at faster speed, which may result in
too many errors in one CRC block, which means the data won't be recoverable
anymore. In other words, the higher the 'recording speed', the more you can
fit on a tape, the faster it will load, but the more chance the data can't
be read. Either use a slower recording speed or buy new high quality tapes.
You get the point. Depending, therefore, on tape length and recording
speed, the total amount of bytes that will fit on one tape will vary.
Suffice to say that you will be able to fit 32k on it at least every 10
minutes, worst case by far. Probably more around to 2-3 minutes. Of course
you can't run the software directly from tape. How will the processor
access it?

like this perhaps?

Tell user to turn tape on.
Get one byte.
Tell user to turn tape off, about a microsecond later.
Process that single opcode.
repeat.

Hum, well, that turns the processor into a 0.0001 Hertz rather than a 6Mhz,
and you have to turn your tape on or off for, oh, a few thousand times per
program? think... think...

--
-R.Zwitserloot@BTInternet.com

Inwoo Kim <ti92@JUNO.COM> wrote in article
<19970708.190147.7631.1.TI92@juno.com>...
> how big is the tape
> is it those microcassetes or those regular ones
> are you going to sell them or do we make them
> what is the memory capacity
> can you run the software directly from the tape??


References: