entrypoint:                   ;at power_up
    gate=input/highz
    data=input/highz
    wait 50 ms
    data=output/low
    wait 850 ms
    gate=output/low
    wait 314 ms
  loop:
    wait 72 ms                  ;pause (eighteen "1=low" bits)
    sendbyte("S")               ;1st letter
    sendbyte("C")               ;2nd letter
    sendbyte("E")               ;3rd letter
    sendbyte(...)               ;4th letter (A, E, or I, depending on region)
    goto loop
  sendbyte(char):
    sendbit(0)                  ;one start bit (0=highz)
    for i=0 to 7
      sendbit(char AND 1)       ;output data (LSB first)
      char=char/2
    next i
    sendbit(1)                  ;1st stop bit (1=low)
    sendbit(1)                  ;2nd stop bit (1=low)
    return
  sendbit(bit):
    if bit=1 then data=output/low elseif bit=0 then data=input/highz
    wait 4 ms           ;4ms per bit = 250 bits per second
    return