AVR code for ATTiny85 which counts pulses from a rotary phone dialer and outputs the corresponding DTMF tone on the phone line.
Modified from the original work by Boris Cherkasskiy - http://boris0.blogspot.ca/2013/09/rotary-dial-for-digital-age.html
Modified by Arnie Weber. GPL license, all text above and below must be included in any redistribution
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