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

Subject: Re: [stella] I did it!(SFCaves 2600)
From: Erik Mooney <emooney@xxxxxxxxxxxxxxxx>
Date: Tue, 03 Oct 2000 02:11:17 -0400
>> from memory, JMP instructions are 4 cycles, not 3.  They're nearly always
>> slower than branches
>Ya, but I didn't really have a choice.  Bensema's guide to cycle counting
>says 3.

My reference says 3, which is the same as a conditional branch -- and I
was wrong before when I said it takes an extra cycle if it crosses a page
boundary -- it doesn't.

Note that if you're jumping less than 128 bytes, it is more efficient to
use some conditional branch that will always be taken, instead of a JMP,
because the former will be 2 bytes long and the latter is always 3.

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