Using LEDs, LCDs and GLCDs in Microcontroller Projects

7.4 Example GLCD Display

An example program is given in this section, to show how the various GLCD library functions can be used. The example program listing is shown in Figure 7.5. Notice that at the beginning of the program, PORT B and PORT D I/O pins are configured as digital by clearing ANSELB and ANSELD registers to 0. This is necessary, since we are using a PIC18F45K22 type microcontroller. Different PIC microcontrollers may require different settings to configure their analogue ports as digital. The images displayed by this program are shown in Figure 7.6. This image was obtained by connecting a GLCD to the EasyPIC 7 development board. The following shapes are drawn on the GLCD:

• a rectangle with rounded edges at co-ordinates (5, 5), (123, 59) and edge radius 10;
• a rectangle at co-ordinates (15, 15), (113, 49);
• a line from (50, 30) to (70, 30);
• a circle with centre at (30, 30) and radius 10;
• a filled circle with centre at (50, 42) and radius 5;
• text ‘Txt’ at x co-ordinate 80 and page 3;
• text ‘LCD’ at x co-ordinate 80 and page 4;
• text ‘micro’ at co-ordinates (80, 38).

The functions used to display each image are also shown in Figure 7.6.

Figure 7.5 Example GLCD program

Figure 7.6 Images displayed by the program in Figure 7.5