; NES PowerPad Test Card (U) zero-page aliases - Pass 2
; Semantic names for addresses with observed usage patterns.

Zp00               = $00 ; PPUCTRL shadow register
Zp01               = $01 ; PPUMASK shadow register
Zp02               = $02 ; VBlank flag (set by NMI, cleared by WaitForVBlank)
Zp03               = $03 ; Frame counter / NMI tick counter
Zp05               = $05 ; Score/digit temp
Zp06               = $06 ; Pad 1 state byte 1 (shifted pad data)
Zp07               = $07 ; Pad 1 state byte 2
Zp08               = $08 ; Pad 1 state byte 3
Zp09               = $09 ; Pad 1 state byte 4
Zp0A               = $0A ; Pad 2 state byte 1
Zp0B               = $0B ; Pad 2 state byte 2
Zp0C               = $0C ; Pad temp / swap variable
Zp0D               = $0D ; Pad mode / draw flag
Zp0E               = $0E ; Shift counter / temp
Zp0F               = $0F ; Delay counter
Zp10               = $10 ; VRAM pointer low byte (indirect)
Zp11               = $11 ; VRAM pointer high byte (indirect)
Zp12               = $12 ; Score digit 1 accumulator
Zp13               = $13 ; Score digit 2 accumulator
Zp14               = $14 ; Score digit 3 accumulator
Zp15               = $15 ; Score digit 4 accumulator