Re: A89: Re: HW1/2 Grayscale Speed (was Re: Grayscale Troubles)

To: assembly-89@lists.ticalc.org
Subject: Re: A89: Re: HW1/2 Grayscale Speed (was Re: Grayscale Troubles)
From: Olle Hedman <oh@hem.passagen.se>
Date: Sat, 05 Aug 2000 13:38:57 +0200
References: <20000804222721.091A8A403E@towerguard.edu.sollentuna.se> <006501bffe84$582dd4c0$d802e0c7@Pnoveck>
Reply-To: assembly-89@lists.ticalc.org

Scott Noveck wrote:
> movem.l (a0),d0-d4        ;12+8n= 52
> movem.l d0-d4,(a1)        ;8 +8n= 48
> adda.w #10,a0             ;        6
> adda.w #10,a1             ;      + 6
>                           ;----------
> ;[repeat 100 times]       ;      112 x 100 = 11,200 clocks
> ;Big thanks for Niklas for helping me shave off those 2,000 clocks
> 

hmmm. I think you have some errors in your calculations here.
acording to my books, adda.w  takes 8+ea calculation, wich is 8 cycles for an
immediate.  that changes thoose 6+6 to 16+16. totals 13,200 cycles then.
lea 10(a0),a0  and lea 10(a1),a1 takes only 8 cycles each, and needs no ea calc.
that takes it down to 11600 cycles.

adda.l takes 6 cycles, maybe that is what you have seen? But if so, you have
forgotten to add ea calculation time anyway.

//Olle

References:

From:

A89: Re: HW1/2 Grayscale Speed (was Re: Grayscale Troubles)

From: "Scott Noveck" <noveck@pluto.njcc.com>

Prev: Re: A89: Re: Re: Re: Re: Grayscale troubles
Next: Re: A89: ooops (was Re: interrupts in C code)
Index(es):
- Main
- Thread