Post by thread:On T: Is there a FM/MFM implementation for PICs th

Hello, I'd like to ask if someone on this list has written some implementation of a FM or MFM modem using a PIC and placed it on his web page ? I'm about to write such a thing and I'd like to see what others have done. I'm looking for slow data rates (300-2400 Baud), simplex, confirmed operation (i.e. a la Xmodem), but high reliability using ECC and/or more than CRC checksums. I will use very short data packets (probably 8 or 16 bytes of data in a packet of up to 32 bytes). thanks, Peter

At 06:56 PM 7/31/98 +0000, you wrote: > I'd like to ask if someone on this list has written some implementation >of a FM or MFM modem using a PIC and placed it on his web page ? > > I'm about to write such a thing and I'd like to see what others have >done. I'm looking for slow data rates (300-2400 Baud), simplex, confirmed >operation (i.e. a la Xmodem), but high reliability using ECC and/or more >than CRC checksums. I will use very short data packets (probably 8 or 16 >bytes of data in a packet of up to 32 bytes). > Hi Peter, Check http://www.baycom.de there is a PIC based GMSK modem for FM radios, it's 9600 baud or higher, AX25 protocol Jerry Meng, BA1FB spam_OUTba1fbTakeThisOuTqsl.net http://www.qsl.net/ba1fb

Or if you're interested in a cheap, software only solution, check out the Scenix SX (Super '5x). Scenix has a newly revised webpage with 1200 Baud FSK and DTMF Transmit & Receive routines in their 'virtual peripheral' library. These might even help get you started.. http://www.scenix.com {Original Message removed}

Jerry Meng wrote: > Check http://www.baycom.de there is a PIC based GMSK modem for FM > radios, it's 9600 baud or higher, AX25 protocol Nice concept reference, but like most *commercial* sites, which is is, it contains an illegible .GIF of the circuit and no code. Hang on, it apparently has the circui in Postscript format if you can view that! If you purchase one, you may get the circuit, but the PIC is secured. Doesn't answer the original query which was "Public Domain" *and* "FM/MFM". Hey! Good try anyway. -- Cheers, Paul B.