NOTES: (THIS IS THE NEW "ONECHIP VERSION" OF SIO2PC.)››There is one integrated circuit, all of the little triangle symbols belong›belong to it.  The 232 sections convert TTL logic (Atari)›to RS232 logic (PC) levels and vice versa.››Atari SIO connector pin #'s are given on the left.  The colors are what I›find when I cut a standard SIO cable in half.  The pin #'s on the right are›for the PC's serial port connector.  The colors are arbitrary. For some›troubleshooting, here's what I find when the interface is plugged into the›Atari but not the PC: (with respect to ground)›Pin 2 of PC connector:  -9.4 volts (approx)›Pin 9 of PC connector:  +9 volts;  Pin 2 of 232: +10 volts;›Pin 6 of 232: -10 volts; Pin 16 of 232: +5 volts›Pin 15 of 232: 0 volts›                                              ›   1 2 3 4 5             2 4 6 8 10 12        |WARNING: BUILD AND USE THIS |›    6 7 8 9             1 3 5 7 9 11 13       |DESIGN AT YOUR OWN RISK!    |›  View of the rear      View of the SIO       |ACCEPT ALL RESPONSIBILITY OR|›of the DB-9F connector  jack on the Atari     |DO NOT BUILD THE INTERFACE  |›for the serial port of  console.              |OR RUN THE SOFTWARE!        |›the PC.                                       |                            |›                                              ›         SIO2PC SCHEMATIC pg 3 of 3››