I'm developing a PIC based device which communicates with the
host via DTMF tones & uses a Mitel MT8870D to do DTMF decoding.
The device gets the tones over an audio patch cord from the
sound card in the host PC, so it's a low noise situation.

I'm concerned about data rate - there's a serial EEPROM on the
board that I'm trying to fill, and would like to be reasonably
quick about it.

Does anybody have any experience in this sort of situation with
trying to improve data transfer rate in this situation?

the standard minimums are 40ms tone + 40ms interdigit silence,
or 160ms/byte - at which rate it could be a while before I see
the end of that 500 byte transmission.


--
Anniepoo
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