This is a bit disjointed as I am running out of time and also helping on chat.
Hey since u have been around pics longer and obviously know more which pic can u recommend to top the 18f4620 in speed and ram?
Some of the 18F family go up to 16 MIPS which is 6 Mips faster then the 18F4620. A good example is the **broken link removed**. But there is a problem.
The problem is that it is not supported by PICkit2 for program or debug. It is supported by ICD2 so if you have a inchworm and the companion board that converts it to USB you are in buisness.
I am guessing it is a speed issue with the PICkit2 and none of the chip over 40 Mhz (10 MIPs) will work with it. Not 100% sure.
You could move up to 24s and dsPICs but I do not think that is what you are looking to do.
Also you need to check the datasheet on the 4620.
"The HSPLL mode makes use of the HS Oscillator
mode for frequencies up to 10 MHz. A PLL then multiplies
the oscillator output frequency by 4 to produce an
internal clock frequency up to 40 MHz."
In short you can not use a 20MHz crystal and the PLL. You need to use a 10MHz and the PLL for 40MHz aka 10Mips..
3v0