On Tue, Jan 16, 2018 at 6:59 PM, Anders Nelson via cctalk <[email protected]> wrote: > Silvertel makes POTS line interfaces (SLICs) that work on 3.3v or 5v > supplies. They do all the high voltage generation and impedance wizardry on > the POTS side, then expose audio in/out and simple control lines.
I've worked with early versions of SLIC - circa 1990... even then, they packed enormous amounts of telco stuff in a small package. One place I worked for made a 2-line telco simulator product - the primary use was testing auto-dialling software to replicate various fault conditions. > To complete the picture you'd have to generate the tones and decode the > numbers but that's it I'm guessing. > > Practical? No. Awesome? Yes. We did that with an 8749 (MCS-48) microcontroller. By dialling different phone numbers from one of the stations, the MCU would complete a connection or play a busy or fast busy signal. -ethan
