OK, I'm reviewing some documentation for the 18F2620.  I'm going to  
try and avoid printing 412 pages of documentation, so for the time  
being I'll refer to the pdf datasheet as needed.

I created a new project in MPLAB, and am going to begin using the  
MPASM tool suite.  I've copied the template file for the 18F2620 and  
renamed it simply, "blinky" as a basis to begin my project.

One thing I immediately see that appears different from the 16F series  
is how the configuration bits are defined

;Configuration bits
;Microchip has changed the format for defining the configuration bits,  
please
;see the .inc file for futher details on notation.  Below are a few  
examples.

(I don't know where to find this 'inc' file mentioned)

;   Oscillator Selection:
     CONFIG	OSC = LP             ;LP

(OK, I can see this means 'low-powered crystal'. )

So far, so good.   On the pull down menu, however, under 'configure,  
configuration bits' there is a check box to either set the bits in  
code (default, it seems) or to select from the individual fields.  I'm  
new enough at this to not know what needs to be set (ie _MCLRE_ON &  
_CP_OFF &  _WDT_OFF) as I might have done with a 16F84.  If I am  
understanding these functions, it appears I would set them the same  
way as I did previously, and if the default condition is correct, no  
further action needs to be done.  I might assume that setting the bits  
in code is preferred over the pull down configuration to allow you as  
well as anyone else to see what is configured.

Bear with me here...  I'm trying this out on paper before ever  
plugging anything into the breadboard.

I want to light a single LED on RB0 of the 18F2620.

list			p=18F2620
#include		<p18F2620.inc>

CONFIG 	OSC=LP					;I'll use a 20MHz crystal at OSC1 & OSC2


start
		CLRF		PORTB				;initialize port B
		MOVLW		b'11111110'			;configure RB0 as output
		MOVWF		TRISB
		MOVLW		b'00000001'			;set RB0 high
		MOVWF		TRISB

		goto		$


As Olin suggests, I came up with this by quickly looking at sections  
of the datasheet.  Much extensive study is obviously required.  My  
next step should be to see if this compiles - IT DOESN'T.   I receive  
errors such as:   Executable code and data must be defined in an  
appropriate section.  I'll need to learn what that means.

At any rate, if someone can let me know if I'm on the right track to  
start.

Thanks.

Joe






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