But, in "Glcd.pdf" what is the crystal oscillator frequency?
As metioned above, the examples are for a 4Mhz oscillator, the 18F series and some 16F chips have internal oscillators as well as the external crystal option.
In the same pdf, it was mentioned that
No reason why the code could not be converted to the16F chips, with some work.
I didn't get this above statement.
The Assembly code used on the 18F chips is just an extension of the 16F Assembly.
However there are some important differences that must be changed to make the code work on the 16F chip.
While an experience users would not find that too difficult, its not something I would suggest for a beginner to try.
Has any one tried with PIC16F micro-controllers ?
I have not seen any 16F assembly code, thats why I wrote my own from the beginning,
Can I know the reason for choosing PIC18F in "Glcd.pdf"?
I used to use the 16F chips but the 18F as very similar prices and have the advantate of being easier to program in Assembly, have more memory and functions.
As an alternative you could look at using Pic C, some compilers
may have EADOG modules ready made.
If you look at the Arduino micro systems then they have free EADOG libraries and you can have a display working in minutes, picture below shows mine running on an Arduino Uno. They are programmed in C++ and have plenty of help and working projects.