I know that some PIC devices have I2C hardware that simplifies acting
     as a slave, but I wonder if anyone has had any luck writing software
     only I2C slaves. If so, did doing it in software create any
     limitations (cannot have multiple slaves, for instance). I believe I
     have read somewhere that certain collision types are dificult to trap
     without dedicated hardware, or it it just without interrupts?


     TIA - Martin.