GPS Clock - Time and Date

This project decodes the RS-232 output from a GPS receiver and
displays the time and date values from the $GPRMC string on
a 2-line x 8-character LCD.

The top line displays hours, minutes and seconds of UTC time.

If the GPS data is valid, denoted by the character "A" in array
position 14, the lower line displays the UTC date. It displays
the warning "No Fix" if the fix data is invalid.

The "No Fix" pin is reset to low if the fix is valid. If the fix
becomes invalid, the LED pin is set high to turn on a warning LED.

The message "No Data" is posted if the RS232 input fails at any time.

Compiled with SourceBoost BASIC for the PIC microprocessor

'****************************************************************
'                         16F688                                *
'                       +---------+                             *
'                     1 |         | 14                          *
'            5.0 V  ----+         +----  GND                    *
'                     2 |         | 13                          *
'           xtal    ----+         +----  RA0   "No Fix" LED     *
'   3.6864 MHz        3 |         | 12                          *
'           xtal    ----+         +----  RA1    RS              *
'                     4 |         | 11                          *
'              RA3  ----+         +----  RA2    E               *
'                     5 |         | 10                          *
'               RX  ->--+         +----  RC0    DB4             *
'                     6 |         | 9                           *
'               TX  -<--+         +----  RC1    DB5             *
'                     7 |         | 8                           *
'       DB7    RC3  ----+         +----  RC2    DB6             *
'                       |         |                             *
'                       +---------+                             *
'                                                               *
'****************************************************************

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