Patent ID: 7116739

Claim:
A method comprising: (a) receiving a frame of an incoming asynchronous serial signal onto a single pin communication interface, wherein the single pin communication interface is implemented as an open drain interface and is usable for half-duplex, bi-directional communication, the frame including a plurality of bits, the plurality of bits including a start bit, a number of data bits, and at least one stop bit; (b) counting a number A of reference clocks during a time that a number N of the plurality bits is being received, wherein the number N is greater than one, wherein the reference clocks are reference clocks of a reference clock signal, wherein each cycle of the reference clock signal has a reference clock period T; (c) dividing the number A of clock cycles by the number N, thereby obtaining a baud rate value C and a remainder value R; (d) using the baud rate value and the remainder value to generate an outgoing asynchronous serial signal, wherein the outgoing asynchronous serial signal comprises a frame, the frame comprising the number N of bits, each bit of the frame of the outgoing asynchronous serial signal having a duration of either a first duration or a second duration, wherein the first duration is a time substantially equal to the reference clock period T times the baud rate value C, wherein the second duration is a time substantially equal to the reference clock period T times the baud rate value C plus one, wherein there are approximately R bits of the second duration in the frame of the outgoing asynchronous serial signal, and wherein the R bits of the second duration are spread over the N bits of the frame of the outgoing asynchronous serial signal; (e) outputting the outgoing signal onto the single pin communication interface; and (f) detecting a break condition by detecting a condition when a voltage on the single pin communication interface is held at a first polarity for more than the length of time it takes to transmit a frame of the outgoing asynchronous serial signal, wherein the start bit of the received frame is of the first polarity.