hi;
i wana display battery charging level on a bargraph LCD using pic16c54c. Data is on four input pins of pic from circuit. normally there are simple dc inputs on all pins, but when battery is 20% charged then all inputs contains DC. when it is 40%Charged then one of the 4 pins contain 100hz frequency with 70%duty cycle. when it is 60% charged then two inputs have 100hz frequency. when it is 80% charged then 3 inputs have 100hz signal. and when it is 100% charged finally then all the pins have 100hz signal...
Now accordingly 1,2,3,4,5 bars should be displayed on the LCD , and for this just 60hz square wave is sent on LCD...
how should i code the logic in C.
1) To generate 60hz signal at the output.
2) To detect Rising or falling edge at the input.

Regards