; Mermaids of Atlantis (U) - zero-page aliases.
;
; Pass 1 names every zero-page operand ZpXX; the names below are the
; semantic ones the dump proves.  An address whose role is the same at
; every reference is renamed everywhere; an address the game reuses for
; several roles keeps the neutral ZpXX name and is listed at the end.

ButtonState1     = $26 ; player 1 button bits, read from $4016
ButtonState2     = $27 ; player 2 button bits, read from $4017
PrevButton1      = $28 ; player 1 buttons of the previous frame
PrevButton2      = $29 ; player 2 buttons of the previous frame
NewButton1       = $2A ; player 1 buttons pressed this frame
NewButton2       = $2B ; player 2 buttons pressed this frame
PrgBankNumber    = $2C ; the MMC3 PRG bank the game switches to
HandlerIndex     = $2D ; the index the banked call dispatches on
IdleCounter      = $2F ; the counter the idle loop spins on
FrameCounter     = $31 ; the frame counter, incremented at the end of the NMI
ControllerBits   = $05 ; the eight button bits assembled by the pad reader
ControllerByte   = $07 ; the raw byte read from $4016/$4017
GameMode         = $6A ; the game mode flag (0 = playing, 1 = demo)

; ---------------------------------------------------------------------------
; The addresses below are used for more than one purpose in this dump, so
; they keep the neutral name.
;
;   $00-$01  the RAM-clear pointer (and the banked-call scratch)
;   $02      the PPUMASK shadow
;   $06      the PRG bank shadow in the banked call
;   $11-$14  indirect pointers: the VRAM pointer, the dispatch table pointer
;            and the sound table pointer share the two pairs
;   $19-$1F  scroll, sprite and bubble coordinates, reused per actor
;   $20-$2E  per-actor scratch: the tile, the position and the frame counters
;   $30-$3F  per-actor state: the sprite index, the direction and the timers
;   $40-$5F  the level script variables: the stage, the wave and the score
;   $60-$7F  the game state: the mode flags, the player state and the timers
;   $80-$9F  the same, for the second half of the image
;   $A0-$DF  the sound engine state
; ---------------------------------------------------------------------------

Zp2E    = $2E
Zp00    = $00
Zp01    = $01
Zp02    = $02
Zp03    = $03
Zp04    = $04
Zp06    = $06
Zp08    = $08
Zp09    = $09
Zp10    = $10
Zp11    = $11
Zp12    = $12
Zp13    = $13
Zp14    = $14
Zp15    = $15
Zp16    = $16
Zp17    = $17
Zp18    = $18
Zp19    = $19
Zp1A    = $1A
Zp1B    = $1B
Zp1C    = $1C
Zp1D    = $1D
Zp1E    = $1E
Zp1F    = $1F
Zp20    = $20
Zp21    = $21
Zp22    = $22
Zp23    = $23
Zp24    = $24
Zp25    = $25
Zp30    = $30
Zp32    = $32
Zp33    = $33
Zp34    = $34
Zp35    = $35
Zp36    = $36
Zp37    = $37
Zp38    = $38
Zp39    = $39
Zp3A    = $3A
Zp3B    = $3B
Zp3C    = $3C
Zp3D    = $3D
Zp3E    = $3E
Zp3F    = $3F
Zp40    = $40
Zp41    = $41
Zp42    = $42
Zp46    = $46
Zp47    = $47
Zp48    = $48
Zp49    = $49
Zp4A    = $4A
Zp4B    = $4B
Zp4C    = $4C
Zp4D    = $4D
Zp4E    = $4E
Zp52    = $52
Zp56    = $56
Zp58    = $58
Zp59    = $59
Zp5A    = $5A
Zp5B    = $5B
Zp5C    = $5C
Zp5D    = $5D
Zp5E    = $5E
Zp5F    = $5F
Zp60    = $60
Zp61    = $61
Zp62    = $62
Zp63    = $63
Zp64    = $64
Zp65    = $65
Zp66    = $66
Zp67    = $67
Zp68    = $68
Zp69    = $69
Zp6C    = $6C
Zp6E    = $6E
Zp6F    = $6F
Zp70    = $70
Zp71    = $71
Zp72    = $72
Zp73    = $73
Zp74    = $74
Zp75    = $75
Zp76    = $76
Zp78    = $78
Zp7E    = $7E
Zp80    = $80
Zp85    = $85
Zp86    = $86
Zp91    = $91
Zp93    = $93
Zp94    = $94
Zp95    = $95
Zp96    = $96
Zp97    = $97
Zp99    = $99
Zp9A    = $9A
Zp9D    = $9D
ZpA7    = $A7
ZpAF    = $AF
ZpB7    = $B7
ZpB9    = $B9
ZpBE    = $BE
ZpC8    = $C8
ZpC9    = $C9
ZpCA    = $CA
ZpCB    = $CB
ZpCC    = $CC
ZpCD    = $CD
ZpCE    = $CE
ZpCF    = $CF
ZpD0    = $D0
ZpD4    = $D4
ZpD5    = $D5
ZpD6    = $D6
ZpD7    = $D7
ZpD8    = $D8
ZpD9    = $D9
ZpDA    = $DA
ZpDB    = $DB
ZpDC    = $DC
ZpDD    = $DD
ZpDE    = $DE
ZpDF    = $DF
ZpE0    = $E0
ZpE2    = $E2
ZpE3    = $E3
ZpE7    = $E7