[stella] 6502 question (was INV+ ... )

Subject: [stella] 6502 question (was INV+ ... )
From: "Erik Mooney" <erik@xxxxxxxxxx>
Date: Tue, 6 Apr 2004 15:53:19 -0500
cybergoth@xxxxxxxx wrote:

> Details!
> Greetings,
> Manuel

Patience! :)

But it would help if anyone knows this.  Does anyone have a 6502 
reference as to exactly what JSR does on a cycle-by-cycle basis?

I'm asking because I'm trying to do something crazy: hit
RESP0 and RESP1 with fewer than 3 cycles difference.  The only
6502 instruction that can (maybe) do two zeropage writes that
fast is JSR.  If the stack pointer is set to RESP1, then JSR 
would write to RESP1 and then RESP0 very quickly (the values
written would be the current PC, but that's irrelevant.)

ldx #RESP1
JSR nextinstruction

Is that possible?  How close together will P0 and P1 end up?
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