Re: [Discuss-gnuradio] gmsk2 - CRC and whitening

[Robert Cicconetti]

I've got some half working code for an APRS tracker targeting an -8515.
Doesn't have a crc routine built in (didn't get that far). Maybe one of
these days I'll finish it. :) At some point I did have multimon
decoding my test packet, but I can't guarantee that this is the version
that actually worked. :)

As I recall, it's set to use a 3.6864 Mhz oscillator and to generate
1200/2200 baud signals. It implements a basic HDLC NRZI encoding, and a
software DDS. Data comes out PORTC. Running a 10 khz sample clock, the
beast was asleep most of the time, waiting for a counter to fire.

You're welcome to borrow anything you want from it, although I won't
guarantee anything actually works on it.. haven't touched this code in
ages. Rather crufty, although it is heavily commented. :) It will
currently send out packets containing "TestingTesting" and my call
sign. Remember that if you change the packet, you need to change the
CRC16 at the end.

R C

On 12/1/05, Daniel O'Connor <address@hidden> wrote:

On Fri, 2 Dec 2005 09:27, Eric Blossom wrote:
> > Processor - Atmel AT90S8535 - face turns beat red. =)
>
> The AVR processors are very nice.  Sort of a minature RISC architecture.
> You've got 8K of flash, so I don't see any problem at all.  I think
> there's a port of GCC that targets it too.

There sure is :)
http://savannah.nongnu.org/projects/avr-libc
http://www.nongnu.org/avr-libc/

The 8535 is pretty crusty though ;)

fsk3.c
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