Re: [stella] Weird Loop...

Subject: Re: [stella] Weird Loop...
From: "Thomas Jentzsch" <tjentzsch@xxxxxx>
Date: Wed, 6 Dec 2000 18:36:25 +0100
Manuel Polik wrote:
> In Starmaster I found this loop:
>        LDX    #$18
> Loop:  STA    WSYNC
>        LDA    VSYNC
>        NOP
>        NOP
>        NOP
>        NOP
>        DEX
>        BPL    Loop
> Now, I've no clue, what the LDA VSYNC & the NOPs are for...
> Can someone explain that to me? 

LDA VSYNC is a problem of DiStella, it doesn't show read accesses correct (should be LDA CXM0P). Try the trace-mode of z26, there you will find the right code and some more valuable information.
The NOPs are used for the following routine, where some player positioning happens (I think, they could have moved those NOPs behind the loop).

Thomas Jentzsch         | *** Every bit is sacred ! ***
tjentzsch at web dot de |
Alles unter einem Dach: Informationen, Fun, E-Mails. Bei WEB.DE:
Die große Welt der Kommunikation: E-Mail, Fax, SMS, WAP:

Archives (includes files) at
Unsub & more at

Current Thread