Connect PORTC.2 of 16F877 to PWM IN.
Connect Vee on LCD to Vee Out.


'**************** LCD Display Negative Voltage ********************
'********************* 16F877 @ 20 MHz ****************************

PR2=255              ' Set PR2 to 19.53 kHz
CCPR1L=230           ' Set Pulse width - CCPR1L must be less than PR2.
                     ' Lower number(pulse width)=higher view angle 
                     ' PR2 value is 100% duty cycle.
                     ' PR2/2 = 50% duty cycle.
TRISC.2=0            ' Set CCP1 bit as output
T2CON=%00000100      ' Timer on prescale is 1
CCP1CON=%00001100    ' Set PWM Mode
'******************************************************************