Re: [stella] I did it!(SFCaves 2600)

Subject: Re: [stella] I did it!(SFCaves 2600)
From: "John K. Harvey" <jkharvey@xxxxxxxxxxxxxxxxx>
Date: Sun, 01 Oct 2000 23:23:18 -0500
>excuse me, but the only unconditional "branch" that takes 3 cycles is JMP
>absolute, and it takes 3 cycles regardless of the contents of the
>operand...perhaps you were referring to BRA or branch always?  or maybe
>something else...

There is no BRA in the 6507 architecture.  Only
All should be 2 cycles if the branch is not taken.

LDA NotZero
BEQ Back

Not taking the branch will only take 2 cycles.  No modification of the PC
occurs, save for its increment.

Always be sure to check that page boundary condition, tho.  I had some
issues with that in PG2.

	-John K. Harvey

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