02/08/90
AST RESEARCH TECHNICAL BULLETIN TB-0064                  10-11-84
  

                      SERIAL PORT WRAP PLUG


In  order to test the complete circuitry of the serial port on an 
AST  board (when running IBM diagnostics) there must  be  signals 
coming  into the port.   This may be accomplished by installing a 
wrap plug on the serial port connector.  To construct a wrap plug
use  a standard RS232 DB25 female connector and wire  these  pins 
together.


                    2  >  3

                    4  >  5  >  22

                    6  >  8  >  20


* Use 30 AWG wire or greater.