Few months ago I got one of those old analog dial-based phones. Since the pulse-dialing technique is kinda deprecated nowadays I made an atmega48p-based board to capture the input numbers from the rotary dial and translate them into "modern" DTMF pulses using a DAC converter made with a R-2R resistor ladder.
More info about this project available on my website and hackaday.io.
- make all to compile
- make flash to upload
- make fuses to set the fuses (for an atmega48p)