This is an adjustable PWM ++duty with a fixed frequency 133Hz, steps UP and DWN by 1 to adjust the the ++duty.
An LCD HD44780 displays the steps from 0 to 34, which are from 0 degree to more than 180 degree.
A micro-switch connected to RA0 decrease ++duty duration, other to RA1 increase ++duty duration, RA3 is the PWM output
RB0-RB3 connected to LCD D4-D7, RB4->E, RB5->RS, R/W->GND
The width and the frequency displayed in LCD are only for information they are not adjustable by Switches.
This material can be used for free, but for your own risk!