[stella] Weird Loop...

Subject: [stella] Weird Loop...
From: Manuel Polik <manuel.polik@xxxxxxxxxxx>
Date: Wed, 06 Dec 2000 10:33:26 +0100
Hi there!

In Starmaster I found this loop:

       LDX    #$18
Loop:  STA    WSYNC
       LDA    VSYNC
       NOP
       NOP
       NOP
       NOP
       DEX
       BPL    Loop

It's used for drawing 25 blank lines showing nothing, when displaying
the Map screen. 
(The space between the actual Map and the status lines)
Now, I've no clue, what the LDA VSYNC & the NOPs are for...
Can someone explain that to me? 

Wouldn't -

       LDX    #$18
Loop:  STA    WSYNC
       DEX
       BPL    Loop

- do exactly the same?!?

(On a first guess I'd say it's just to confuse poor reverse-engineers
like me...)

Greetings,
	Manuel

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