TouchClock : Design your own GLCD Clock

TouchClock Video Clip

Credits to CircuitED for his beautiful GLCD touchscreen, please visit :

to find GLCD module and touchpanel datasheets. Thank you Warren !

DownLoad TouchClock Project

Includes :

mikroC project files for PIC18F452, PIC18F4620, PIC18F4685
TouchClock C source code
TouchScreen C source code library
.HEX files for EasyPIC3 board, may work with EasyPIC4 and EasyPIC5 with only few adjustments in the C source code

How it works ?

This is how to connect the 4-wire resistive touchscreen to the PIC :

How to connect a 4-write resistive touchscreen to a PIC

This is how the library reads the X raw coordinate of a touch :

X+ and X- are in high Z : RA0 and RA2 are inputs
Y+ is set to +5V : RA3 is output high
Y- is set to 0V : RA1 is output low
X+ voltage is read by ADC
Y+ is set to 0V : RA3 is output low
Y- is set to 5V: RA1 is output high
X- voltage is read by ADC and averaged with X+ value, the result is the raw X coordinate.

The same is then done to read the Y coordinate, please see TSlib.c file in .ZIP file above.

X and Y raw coordinates are then adjusted using calibration coordinates to get X and Y coordinates in pixel.