Quote Originally Posted by earltyso View Post
I am finally jumping up to the 18F big boy toys....
I just ordered my first 18F4620 to replace a 16f877A I am using in an LCD board with lots of I/O's, 4x20 LCD, TX/RX and such. I have never used this chipset before. Can anyone tell me what to expect for possible programing problems, compatibility issues, and also how to use the internal oscillator of can I use my XT???

I am looking forward to the 4X Kword upgrade which is why I chose this chipset.

I would really appreciate any help.
Should be a piece of cake to do... In my mp3 player project, I went from a 16F877 to a 18F452 to a 18F4620 without changing any hardware, just rewrote the firmware a bit when changing chips.
Just pay attention to the datasheets. Register names vary between PIC families.
If you've got something going, and it isn't going, chances are you haven't read the datasheet far enough.