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Steve · 24 January 2014, 15:11

I think this is the code I used when I first started playing with assembler a few years ago. Its taken from the HowToCode2 guide on back2roots ftp. I remember it worked fine when I tested it on my A1200 so what is the difference between this one and the one just posted by hitchhikr? Some comments would have been nice as I'm just learning asm again from where I left off years ago.

Code:

This code will check for AGA

        move.w	$dff07c,d0
	cmp.b	#$f8,d0
	bne.s	.notaga

	; Do your funky AGA Stuff in here!

.notaga

I understand that the above code is checking for the Amiga 1200/4000 Lisa chipset by comparing the returned value. If the returned value is $FC (11111100) then the chipset is ECS otherwise if it returns $F8 (11111000) then the chipset is AGA. Is this is the best way of detecting AGA? I don't understand why hitchhkrs code is so complicated. Is it just being more thorough?

24 January 2014, 15:11	#5
Steve I Identify as an Ewok Join Date: Jul 2001 Location: North Lincolnshire Age: 45 Posts: 2,356	I think this is the code I used when I first started playing with assembler a few years ago. Its taken from the HowToCode2 guide on back2roots ftp. I remember it worked fine when I tested it on my A1200 so what is the difference between this one and the one just posted by hitchhikr? Some comments would have been nice as I'm just learning asm again from where I left off years ago. Code: This code will check for AGA move.w $dff07c,d0 cmp.b #$f8,d0 bne.s .notaga ; Do your funky AGA Stuff in here! .notaga I understand that the above code is checking for the Amiga 1200/4000 Lisa chipset by comparing the returned value. If the returned value is $FC (11111100) then the chipset is ECS otherwise if it returns $F8 (11111000) then the chipset is AGA. Is this is the best way of detecting AGA? I don't understand why hitchhkrs code is so complicated. Is it just being more thorough? Attached Thumbnails Last edited by Steve; 24 January 2014 at 15:41.