This program uses both the KBD.C and LCD.C drivers to allow keypad entry and LCD display. All keys are echoed except that will clear the display. Either the kbd_getc or lcd_putc may be replaced with getc or putc to use just one device with the RS-232.
The following code, ex_lcdkb.c together with lcd.c and kbd.c demonstrate how to implement key pressed on the 4 x 3 keypad to be display on the 16 x 1 LCD Module and echoed on the RS-232 channel.