The circuit below shows how to interface to an X10 TW523 Module
to a RS-232 Serial communications so that X10 commands can be send
using the serial RS-232 channel.
The following code,
demonstrate how to interfaces to a X10 TW523 unit to RS-232. This program will accept and
send three character codes of the form xyy where x is A-P and yy is 00-1F. Key codes 00-0F
are translated to the key number.