Re: Aw: Re: [stella] Incoming

Subject: Re: Aw: Re: [stella] Incoming
From: Thomas Jentzsch <tjentzsch@xxxxxx>
Date: Wed, 30 Jan 2002 00:00:09 +0100
At 29.01.2002, 21:03, Ben Larson wrote:
> OK OK, here's the kernel code.  It's rather long and
> repetitive, but I've commented all of the main loop
> with the standard Nick Bensema cycle notation. :)

Thanks for the code!


> ; *****************************
> ; * DISPLAY KERNEL SUBROUTINE *
> ; *****************************

> snip
>         LDA (P1Offset),Y                ;[3]+5-6
> snip

I noticed that you count 5-6 cycles for this opcode.

If you align (something like: align 256 + 120) the data P1/P2Offset are
pointing to, then you can avoid the extra cycles for crossing a page.
Then all code in your main kernel has a constant timing, which would
allow you to remove WSYNC and get some more cycles. And that should
allow you to add code for one missile (perhaps even both), and avoid
flicker. 

Have fun!
Thomas                            
_______________________________________________________
Thomas Jentzsch         | *** Every bit is sacred ! ***
tjentzsch at web dot de |

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