Difference between revisions of "Alleyway:ROM map"

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(Created page with ''''Addresses:''' * <tt>0x03B5-03C0</tt> = OAM DMA Transfer subroutine * <tt>0x03C1-03FE</tt> = Joypad subroutine * <tt>0x1C42-????</tt> = Level data <pre> 0x1C42-1D08: First leve…')
 
(Added rommap template.)
 
(2 intermediate revisions by one other user not shown)
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{{rommap|game=Alleyway}}
 
'''Addresses:'''
 
'''Addresses:'''
 
* <tt>0x03B5-03C0</tt> = OAM DMA Transfer subroutine
 
* <tt>0x03B5-03C0</tt> = OAM DMA Transfer subroutine
 
* <tt>0x03C1-03FE</tt> = Joypad subroutine
 
* <tt>0x03C1-03FE</tt> = Joypad subroutine
 +
* <tt>0x07E8-07F1</tt> = Decrease lives
 +
<pre>
 +
00:07E8 FA 44 CA ld a,[$CA44] (Put in A the value in address $CA44=Lives)
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00:07EB FE 00 cp a,$00 (Compare the value of A with $00)
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00:07ED C8 ret z (Return if is zero)
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00:07EE 3D dec a (Decrease a)
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00:07EF EA 44 CA ld [$CA44],a (Sets the value of A in the address $CA44=Lives)
 +
 +
Note:
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If you changes the instruction in 00:07EE, you can have infinite lives.
 +
00:07EE 00              nop            (NOp Operation)
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The lives don´t decreases.
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</pre>
 
* <tt>0x1C42-????</tt> = Level data
 
* <tt>0x1C42-????</tt> = Level data
 
<pre>
 
<pre>
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02: Two bricks. One in the position and other above it.
 
02: Two bricks. One in the position and other above it.
 
....
 
....
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FF: End of level data
 
</pre>
 
</pre>

Latest revision as of 10:58, 19 November 2011

Addresses:

  • 0x03B5-03C0 = OAM DMA Transfer subroutine
  • 0x03C1-03FE = Joypad subroutine
  • 0x07E8-07F1 = Decrease lives
00:07E8	FA 44 CA	ld a,[$CA44]	(Put in A the value in address $CA44=Lives)
00:07EB	FE 00		cp a,$00	(Compare the value of A with $00)
00:07ED	C8		ret z		(Return if is zero)
00:07EE	3D		dec a		(Decrease a)
00:07EF	EA 44 CA	ld [$CA44],a	(Sets the value of A in the address $CA44=Lives)

Note:
If you changes the instruction in 00:07EE, you can have infinite lives.
00:07EE 00              nop             (NOp Operation)
The lives don´t decreases.
  • 0x1C42-???? = Level data
0x1C42-1D08: First levels
0x1D09-1DCD: Other levels

Notes (Bricks values):
00: Without brick
01: One brick
02: Two bricks. One in the position and other above it.
....
FF: End of level data