; Asks the machine what its controllers are doing.
;
; A pad reports a LEVEL and not an event: one read gives every button at once, holding is the
; natural thing to say, and reading does not consume anything - so asking twice in a frame
; gives the same answer twice, which this checks by doing exactly that.
;
; The recording behind it is one byte a frame. It presses up, holds it a second frame, adds
; right, lets go of up, lets go of everything, then presses A and B together - which is the
; case a console's key-at-a-time stream cannot express at all.
;
; Written by Anachronaut

#Program

start:
  INA 0x64
  OUTA 0x00                 ; Which pads are there: one bit each, so pad nought alone is 1.
  RSTA
  SETD.0 Count
  STA.0

everyFrame:
  INA 0x30
  INIB 0x01
  AND
  BRQ everyFrame            ; The frame the recording steps on.

  INA 0x60
  OUTA 0x00
  ; And again, without a frame in between. A level does not go away when it is looked at.
  INA 0x60
  OUTA 0x00

  SETD.0 Count
  LDA.0
  INCA
  STA.0
  INIB 0d6
  CCF
  SUB
  BNQ everyFrame

  ; A pad that is not there reads as nothing held, which is honest rather than an error.
  INA 0x63
  OUTA 0x00
  HALT

#Data

Count:
  0x00