diff --git a/.gitignore b/.gitignore
index 07ad212d..7910a645 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,6 +6,7 @@
 *.pyc
 *.bin
 *.txt
+*.log
 tetris.lst
 tetris.lbl
 tetris.map
diff --git a/gentas.py b/gentas.py
new file mode 100644
index 00000000..7fbb15c9
--- /dev/null
+++ b/gentas.py
@@ -0,0 +1,110 @@
+import argparse
+import logging
+import pathlib
+import sys
+
+logger = logging.getLogger(__name__)
+OFFSET=2
+INPUT_LETTERS = "RLDUTSBA"
+INPUT_VALUES = dict(
+    right=0x80,
+    left=0x40,
+    down=0x20,
+    up=0x10,
+    start=0x08,
+    select=0x04,
+    b=0x02,
+    a=0x01,
+)
+
+
+# TASLINE = "|0|........|||"
+def get_tas_line(input_byte: int):
+    result = []
+    result.extend("|0|")
+    binary = f"{input_byte & 0xFF:08b}"
+    for i, char in enumerate(binary):
+        result.append(INPUT_LETTERS[i] if char == "1" else ".")
+    result.extend("|||")
+    return "".join(result)
+
+def main():
+    parser = argparse.ArgumentParser()
+    parser.add_argument("frames", type=int, help="length of tas")
+    parser.add_argument("-f", "--file", type=pathlib.Path, help="output file (stdout otherwise)")
+    parser.add_argument(
+        "-R",
+        "--right",
+        type=int,
+        nargs="+",
+        default=[],
+    )
+    parser.add_argument(
+        "-L",
+        "--left",
+        type=int,
+        nargs="+",
+        default=[],
+    )
+    parser.add_argument(
+        "-D",
+        "--down",
+        type=int,
+        nargs="+",
+        default=[],
+    )
+    parser.add_argument(
+        "-U",
+        "--up",
+        type=int,
+        nargs="+",
+        default=[],
+    )
+    parser.add_argument(
+        "-T",
+        "--start",
+        type=int,
+        nargs="+",
+        default=[],
+    )
+    parser.add_argument(
+        "-S",
+        "--select",
+        type=int,
+        nargs="+",
+        default=[],
+    )
+    parser.add_argument(
+        "-B",
+        "--b",
+        type=int,
+        nargs="+",
+        default=[],
+    )
+    parser.add_argument(
+        "-A",
+        "--a",
+        type=int,
+        nargs="+",
+        default=[],
+    )
+    args = parser.parse_args()
+
+    output = bytearray(args.frames)
+    for label, value in INPUT_VALUES.items():
+        for frame in vars(args)[label]:
+            # if frame < OFFSET:
+            #     raise RuntimeError(f"{frame} needs to be less than {OFFSET}")
+            output[frame+OFFSET] |= value
+
+
+    output = ('\n'.join(get_tas_line(f) for f in output))
+    if args.file:
+        with open(args.file, 'w+') as file:
+            print(output, file=file)
+    else:
+        print(output)
+
+
+if __name__ == "__main__":
+    main()
diff --git a/maketas.sh b/maketas.sh
new file mode 100755
index 00000000..d9e0f430
--- /dev/null
+++ b/maketas.sh
@@ -0,0 +1,25 @@
+#!/usr/bin/env bash
+
+mkdir -p tases
+
+for i in {100..2000..100}; do
+    python gentas.py $i -f tases/no-start-$(printf '%04d' $i).fm2
+done
+
+python gentas.py 300 -T 265 -f tases/earliest-start.fm2
+python gentas.py 1800 -T 1794 -f tases/latest-start.fm2
+python gentas.py 300 -T 265 270 274 286 -f tases/fastest-999999-start.fm2
+
+python gentas.py 500 -T  400 420 440 460 -f tases/start-pattern-a.fm2
+python gentas.py 800 -T  700 720 740 -f tases/start-pattern-b.fm2
+python gentas.py 1000 -T 900 920 940 -f tases/start-pattern-c.fm2
+
+
+while read -r -d '' tas; do
+    clean="${tas%.*}"-clean.log
+    if ! test -f "$clean"; then
+        echo $clean not found, running test
+        time cargo run --release --manifest-path tests/Cargo.toml -- \
+            parity "$tas" -w
+    fi
+done < <(find tases/ -name "*.fm2" -print0)
diff --git a/src/boot.asm b/src/boot.asm
index 707d2ac2..5f67c1b1 100644
--- a/src/boot.asm
+++ b/src/boot.asm
@@ -30,6 +30,10 @@
         lda #$A
         sta paceModifier
 
+        inc hzFlag
+        inc inputDisplayFlag
+        ; inc darkModifier
+
         lda #$10
         sta dasModifier
 
@@ -80,9 +84,19 @@
         jsr disableNmi
         jsr drawBlackBGPalette
         ; instead of clearing vram like the original, blank out the palette
+; align with vanilla at frame 0004
+        ldx #$0
+        ldy #$20
+@wait:
+        dex
+        bne @wait
+        dey
+        bne @wait
+
         lda #$EF
         ldx #$04
         ldy #$04 ; used to be 5, but we dont need to clear 2p playfield
+
         jsr memset_page
         jsr waitForVBlankAndEnableNmi
         jsr updateAudioWaitForNmiAndResetOamStaging
diff --git a/src/gamemode/branch.asm b/src/gamemode/branch.asm
index b3111a1c..769e5ecc 100644
--- a/src/gamemode/branch.asm
+++ b/src/gamemode/branch.asm
@@ -1,22 +1,328 @@
 ; 2nd and 3rd instances of playAndEndingHighScore_jmp used to be demo and startDemo respectively
 branchOnGameMode:
         branchTo gameMode, \
-            gameMode_bootScreen, \
-            gameMode_waitScreen, \
-            gameMode_gameTypeMenu, \
+            gameMode0, \
+            gameMode1, \
+            gameMode2, \
             gameMode_levelMenu, \
             gameMode_playAndEndingHighScore_jmp, \
-            gameMode_playAndEndingHighScore_jmp, \
+            gameMode2, \
             gameMode_playAndEndingHighScore_jmp, \
             gameMode_speedTest
 
-.include "bootscreen.asm"
-.include "waitscreen.asm"
-.include "gametypemenu/menu.asm"
+; .include "bootscreen.asm"
+; .include "waitscreen.asm"
+; .include "gametypemenu/menu.asm"
 .include "levelmenu.asm"
 
+gameMode0:
+        lda #$00
+        sta renderMode
+
+        ; reset cursors
+        lda #$0
+        sta practiseType
+        sta menuSeedCursorIndex
+
+        ; levelMenu stuff
+        sta levelControlMode
+        lda #INITIAL_CUSTOM_LEVEL
+        sta customLevel
+
+        jsr updateAudioWaitForNmiAndDisablePpuRendering
+        jsr checkRegion
+.if KEYBOARD = 1
+        ; todo test timing for keyboard
+        jsr detectKeyboard
+.endif
+        jsr updateAudioWaitForNmiAndDisablePpuRendering
+        jsr disableNmi
+
+        lda #NMIEnable
+        sta currentPpuCtrl
+.if INES_MAPPER <> 0
+; NROM (and possibly FDS in the future) won't load the 2nd bankset
+; and will instead use the title/menu chrset letters.  This won't be noticeable
+; unless a graphic is added
+        lda #CHRBankSet1
+        jsr changeCHRBanks
+.endif
+         jsr bulkCopyToPpu
+         .addr wait_palette
+        jsr copyRleNametableToPpu
+        .addr legal_nametable
+
+        jsr bulkCopyToPpu
+        .addr legal_nametable_patch
+
+        jsr waitForVBlankAndEnableNmi
+
+        jsr stageBootSprites
+        jsr updateAudioWaitForNmiAndResetOamStaging
+
+        dec sleepCounter
+        jsr stageBootSprites
+        jsr updateAudioWaitForNmiAndEnablePpuRendering
+        lda #$01
+        sta qualFlag
+
+        lda #$00
+        sta frameCounter+1
+gameMode0Loop:
+        lda qualFlag
+        bne @wait
+
+        lda newlyPressedButtons_player1
+        and #BUTTON_START
+        bne @goToGameMode1
+@wait:
+        jsr stageBootSprites
+        jsr updateAudioWaitForNmiAndResetOamStaging
+
+        lda sleepCounter
+        bne gameMode0Loop
+
+        lda frameCounter+1
+        cmp #$02
+        beq @goToGameMode1
+
+        ; this is the point where start can be pressed
+        lda #$00
+        sta qualFlag
+
+        dec sleepCounter
+        bne gameMode0Loop
+@goToGameMode1:
+        inc gameMode
+        rts
+
+
+gameMode1:
+        lda #$00
+        sta renderMode
+
+        ; reset cursors
+        lda #$0
+        sta practiseType
+        sta menuSeedCursorIndex
+
+        ; levelMenu stuff
+        sta levelControlMode
+        lda #INITIAL_CUSTOM_LEVEL
+        sta customLevel
+
+        jsr updateAudioWaitForNmiAndDisablePpuRendering
+        jsr updateAudioWaitForNmiAndDisablePpuRendering
+        jsr disableNmi
+
+        lda #NMIEnable
+        sta currentPpuCtrl
+.if INES_MAPPER <> 0
+; NROM (and possibly FDS in the future) won't load the 2nd bankset
+; and will instead use the title/menu chrset letters.  This won't be noticeable
+; unless a graphic is added
+        lda #CHRBankSet1
+        jsr changeCHRBanks
+.endif
+         jsr bulkCopyToPpu
+         .addr wait_palette
+        jsr copyRleNametableToPpu
+        .addr legal_nametable
+
+        jsr bulkCopyToPpu
+        .addr title_nametable_patch
+
+        jsr waitForVBlankAndEnableNmi
+        jsr stageBootSprites
+        jsr updateAudioWaitForNmiAndResetOamStaging
+        jsr stageBootSprites
+        jsr updateAudioWaitForNmiAndEnablePpuRendering
+        lda #$00
+        sta frameCounter+1
+
+gameMode1Loop:
+        jsr stageBootSprites
+        jsr updateAudioWaitForNmiAndResetOamStaging
+
+        lda newlyPressedButtons_player1
+        and #BUTTON_START
+        bne @goToGameMode2
+
+; this is the point vanilla enters demo mode
+; go to game select menu page instead
+        lda frameCounter+1
+        cmp #$05
+        bne gameMode1Loop
+
+        ; use this for now to signal demo start
+        lda #$01
+        sta qualFlag
+        lda #$5
+        sta gameMode
+        rts
+
+@goToGameMode2:
+        inc gameMode
+        rts
+
+
+gameMode2: ; also game mode 5
+        ; check to see if really demo
+        lda gameMode
+        cmp #$5
+        bne @actually2
+
+        @DEMO_FRAMES = 4759
+        lda #>@DEMO_FRAMES
+        sta endingSleepCounter+1
+        lda #<@DEMO_FRAMES
+        sta endingSleepCounter
+
+
+@actually2:
+
+
+        lda #$00
+        sta renderMode
+
+        ; reset cursors
+        lda #$0
+        sta practiseType
+        sta menuSeedCursorIndex
+
+        ; levelMenu stuff
+        sta levelControlMode
+        lda #INITIAL_CUSTOM_LEVEL
+        sta customLevel
+
+        jsr updateAudioWaitForNmiAndDisablePpuRendering
+        jsr updateAudioWaitForNmiAndDisablePpuRendering
+        jsr disableNmi
+
+        lda #NMIEnable
+        sta currentPpuCtrl
+.if INES_MAPPER <> 0
+; NROM (and possibly FDS in the future) won't load the 2nd bankset
+; and will instead use the title/menu chrset letters.  This won't be noticeable
+; unless a graphic is added
+        lda #CHRBankSet1
+        jsr changeCHRBanks
+.endif
+         jsr bulkCopyToPpu
+         .addr wait_palette
+        jsr copyRleNametableToPpu
+        .addr legal_nametable
+
+        jsr bulkCopyToPpu
+        .addr menu_nametable_patch
+
+        jsr waitForVBlankAndEnableNmi
+        jsr stageBootSprites
+        jsr updateAudioWaitForNmiAndResetOamStaging
+        jsr stageBootSprites
+        jsr updateAudioWaitForNmiAndEnablePpuRendering
+
+
+        lda qualFlag
+        beq @skipDemoShuffle
+        ldx #rng_seed
+        jsr generateNextPseudorandomNumber
+        lda qualFlag ; temporary use to signal demo start
+@skipDemoShuffle:
+
+gameMode2Loop:
+        ; check to see if really demo
+        lda gameMode
+        cmp #$5
+        bne @still2
+
+        dec endingSleepCounter
+        bne :+
+        dec endingSleepCounter+1
+        bne :+
+
+; end demo
+        lda #$2
+        sta gameMode
+
+        lda #rng_seed
+        jsr generateNextPseudorandomNumber
+
+        lda #rng_seed
+        jsr generateNextPseudorandomNumber
+:
+
+
+
+@still2:
+
+        lda newlyPressedButtons_player1
+        and #BUTTON_START
+        bne @goToGameMode3
+
+        jsr stageBootSprites
+        jsr updateAudioWaitForNmiAndResetOamStaging
+        jmp gameMode2Loop
+
+@goToGameMode3:
+        inc gameMode
+        rts
+
 gameMode_playAndEndingHighScore_jmp:
         jsr branchOnGameModeState
         rts
 
 .include "speedtest.asm"
+
+stageBootSprites:
+        ldx #frameCounter+1
+        jsr stageZeroPage
+        ldx #frameCounter
+        jsr stageZeroPage
+
+        ldx #rng_seed_hi
+        jsr stageZeroPage
+        ldx #rng_seed
+        jsr stageZeroPage
+
+        ldx #sleepCounter
+        jsr stageZeroPage
+        ldx #generalCounter
+        jsr stageZeroPage
+
+        ldx #gameMode
+        jsr stageZeroPage
+
+        rts
+
+stageZeroPage:
+        lda oamStagingLength
+        and #$0F
+        asl
+        clc
+        adc #$1A
+        sta spriteXOffset
+        lda oamStagingLength
+        and #$F0
+        clc
+        adc #$20
+        sta spriteYOffset
+        stx byteSpriteAddr
+        lda #0
+        sta byteSpriteAddr+1
+        sta byteSpriteTile
+        lda #1
+        sta byteSpriteLen
+        jmp byteSprite
+
+render_mode_0:
+; rustico's run_until_vblank stops a few cycles into scanline 242 where nmi
+; business is being done and messes up tests.  for testing purposes while nothing
+; is needed in nmi, a minimum amount of wait time is needed so that test polling
+; always reads after game logic but before the nmi affects memory values,
+; specifically the frame counter and rng
+    ldx #$40
+@wait:
+    dex
+    bne @wait
+    rts
diff --git a/src/gamemode/gametypemenu/menu.asm b/src/gamemode/gametypemenu/menu.asm
index f4fb67b1..eaeda36e 100644
--- a/src/gamemode/gametypemenu/menu.asm
+++ b/src/gamemode/gametypemenu/menu.asm
@@ -22,6 +22,15 @@ gameMode_gameTypeMenu:
         sta tmp3
         jsr copyRleNametableToPpuOffset
         .addr   game_type_menu_nametable_extra
+
+        ; account for extra nametable loading time
+        inc frameCounter
+        bne :+
+        inc frameCounter+1
+:
+        ldx #rng_seed
+        jsr generateNextPseudorandomNumber
+
 .if INES_MAPPER <> 0
         lda #CHRBankSet0
         jsr changeCHRBanks
@@ -29,7 +38,8 @@ gameMode_gameTypeMenu:
         lda #NMIEnable
         sta currentPpuCtrl
         jsr waitForVBlankAndEnableNmi
-        jsr updateAudioWaitForNmiAndResetOamStaging
+; skip this wait, rng advanced manually above
+;        jsr updateAudioWaitForNmiAndResetOamStaging
         jsr updateAudioWaitForNmiAndEnablePpuRendering
         jsr updateAudioWaitForNmiAndResetOamStaging
 
diff --git a/src/gamemode/levelmenu.asm b/src/gamemode/levelmenu.asm
index 751b4810..97e6c3d2 100644
--- a/src/gamemode/levelmenu.asm
+++ b/src/gamemode/levelmenu.asm
@@ -28,6 +28,16 @@ gameMode_levelMenu:
         lda #RENDER_LINES
         sta renderFlags
         jsr resetScroll
+
+; skip an nmi cycle to align with vanilla
+        ldy #$10
+        ldx #$00
+@wait:
+        dex
+        bne @wait
+        dey
+        bne @wait
+
         jsr waitForVBlankAndEnableNmi
         jsr updateAudioWaitForNmiAndResetOamStaging
         jsr updateAudioWaitForNmiAndEnablePpuRendering
diff --git a/src/gamemodestate/branch.asm b/src/gamemodestate/branch.asm
index 8ae60ecd..772fb6b5 100644
--- a/src/gamemodestate/branch.asm
+++ b/src/gamemodestate/branch.asm
@@ -1,14 +1,3 @@
-; the return value of this routine dictates if we should wait for nmi or not right after
-; initGameBackground               gms: 1 acc: 0 - ne
-; initGameState                    gms: 2 acc: 4/0 - ne
-; updateCountersAndNonPlayerState  gms: 3 acc: 0/1 - ne
-; handleGameOver                   gms: 4 acc: eq (set to $9) if gameOver, $1 otherwise (ne)
-; updatePlayer1                    gms: 5 acc: $FF - ne
-; next                             gms: 6 acc: $1 ne
-; checkForResetKeyCombo            gms: 7 acc: 0 or heldButtons - eq if holding down, left and right
-; handlePause                      gms: 8 acc: 0/3 - ne
-; vblankThenRunState2              gms: 2 acc eq (set to $2)
-
 branchOnGameModeState:
         branchTo gameModeState, \
             gameModeState_initGameBackground, \
@@ -23,13 +12,12 @@ branchOnGameModeState:
 
 gameModeState_next: ; used to be updatePlayer2
         inc gameModeState
-        lda #$1 ; acc should not be equal
         rts
 
 gameModeState_vblankThenRunState2:
         lda #$02
         sta gameModeState
-        rts
+        jmp updateAudioWaitForNmiAndResetOamStaging
 
 .include "initbackground.asm"
 .include "initstate.asm"
diff --git a/src/gamemodestate/checkforabss.asm b/src/gamemodestate/checkforabss.asm
index 432a4679..7d4977b7 100644
--- a/src/gamemodestate/checkforabss.asm
+++ b/src/gamemodestate/checkforabss.asm
@@ -4,7 +4,10 @@ gameModeState_checkForResetKeyCombo:
         cmp #BUTTON_A+BUTTON_B+BUTTON_START+BUTTON_SELECT
         beq @reset
         inc gameModeState
-        ; acc has to be heldButtons_player1 here
+        cmp #BUTTON_LEFT+BUTTON_DOWN+BUTTON_RIGHT
+        bne @continue
+        jsr updateAudioWaitForNmiAndResetOamStaging
+@continue:
         rts
 
 @reset: jsr updateAudio2
diff --git a/src/gamemodestate/handlegameover.asm b/src/gamemodestate/handlegameover.asm
index 2a6a4afe..cfec037c 100644
--- a/src/gamemodestate/handlegameover.asm
+++ b/src/gamemodestate/handlegameover.asm
@@ -46,5 +46,4 @@ gameModeState_handleGameOver:
         rts
 
 @ret:   inc gameModeState ; 4
-        lda #$1 ; acc should not be equal (always $1 in original game)
         rts
diff --git a/src/gamemodestate/initbackground.asm b/src/gamemodestate/initbackground.asm
index cc9658ac..798ff641 100644
--- a/src/gamemodestate/initbackground.asm
+++ b/src/gamemodestate/initbackground.asm
@@ -45,18 +45,30 @@ gameModeState_initGameBackground:
         sta PPUDATA
 @heartEnd:
 
+
         lda #NMIEnable|BGPattern1|SpritePattern1
         sta PPUCTRL
         sta currentPpuCtrl
         jsr resetScroll
         jsr waitForVBlankAndEnableNmi
+
+
+
+        ; this no longer applies:
+        ; gym setup takes longer than vanilla, skip a frame to line up
+        ; jsr updateAudioWaitForNmiAndResetOamStaging
+
+
+        ; https://github.com/kirjavascript/TetrisGYM/pull/154
+        ; restored wait jsr after mainloop wait inlining
+        ; the changes in this branch may have introduced a bug that have been fixed.
+        ; exact cause tbd (if ever)
         jsr updateAudioWaitForNmiAndResetOamStaging
         jsr updateAudioWaitForNmiAndEnablePpuRendering
         jsr updateAudioWaitForNmiAndResetOamStaging
         lda #$01
         sta playState
         inc gameModeState ; 1
-        lda #0 ; acc should not be equal
         rts
 
 scoringBackground:
diff --git a/src/gamemodestate/initstate.asm b/src/gamemodestate/initstate.asm
index 5bda81a6..23ca3bfd 100644
--- a/src/gamemodestate/initstate.asm
+++ b/src/gamemodestate/initstate.asm
@@ -153,7 +153,6 @@ gameModeState_initGameState:
         lda musicSelectionTable,x
         jsr setMusicTrack
         inc gameModeState ; 2
-        lda #4 ; acc should not be equal
 
 initGameState_return:
         rts
diff --git a/src/gamemodestate/pause.asm b/src/gamemodestate/pause.asm
index a3b5c70f..34fcb550 100644
--- a/src/gamemodestate/pause.asm
+++ b/src/gamemodestate/pause.asm
@@ -17,7 +17,6 @@ gameModeState_handlePause:
         jsr pause
 
 @ret:   inc gameModeState ; 8
-        lda #$0 ; acc must not be equal
         rts
 
 pause:
diff --git a/src/gamemodestate/updatecounters.asm b/src/gamemodestate/updatecounters.asm
index b35e93c5..d3b8f65f 100644
--- a/src/gamemodestate/updatecounters.asm
+++ b/src/gamemodestate/updatecounters.asm
@@ -3,8 +3,6 @@ gameModeState_updateCountersAndNonPlayerState:
         lda #$00
         sta oamStagingLength
         inc fallTimer
-        ; next code makes acc behave as normal
-        ; (dont edit unless you know what you're doing)
         lda newlyPressedButtons_player1
         and #BUTTON_SELECT
         beq @ret
diff --git a/src/gamemodestate/updateplayer1.asm b/src/gamemodestate/updateplayer1.asm
index edf9da24..a00be232 100644
--- a/src/gamemodestate/updateplayer1.asm
+++ b/src/gamemodestate/updateplayer1.asm
@@ -15,5 +15,4 @@ gameModeState_updatePlayer1:
         jsr stageSpriteForNextPiece
 
         inc gameModeState ; 5
-        lda #$FF ; acc from stateSpriteForNextPiece
         rts
diff --git a/src/main.asm b/src/main.asm
index 1fb4c13d..9dbdf24a 100644
--- a/src/main.asm
+++ b/src/main.asm
@@ -17,7 +17,12 @@
 
 .segment    "PRG_chunk1": absolute
 
+; consumes exactly 1 page
+.assert <* = 0, error, "mult_orient needs to be at page boundary"
+.include "data/mult_orient.asm"
+
 ; region code at start of page to keep cycle count consistent
+.assert <* = 0, error, "check_region needs to be at page boundary"
 .include "util/check_region.asm"
 .include "audio.asm"
 
@@ -27,10 +32,6 @@ initRam:
 
 mainLoop:
         jsr branchOnGameMode
-        cmp gameModeState
-        bne @continue
-        jsr updateAudioWaitForNmiAndResetOamStaging
-@continue:
         jmp mainLoop
 
 .include "nmi/nmi.asm"
@@ -92,9 +93,6 @@ mainLoop:
 .include "modes/qtap.asm"
 .include "modes/garbage.asm"
 
-.align $100
-; these tables benefit from page alignment
-.include "data/mult_orient.asm"
 
 .segment    "PRG_chunk3": absolute
 
diff --git a/src/nametables.asm b/src/nametables.asm
index 70dd5f9d..342a48e1 100644
--- a/src/nametables.asm
+++ b/src/nametables.asm
@@ -1,7 +1,7 @@
-game_type_menu_nametable: ; RLE
-        .incbin "nametables/game_type_menu_nametable_practise.bin"
-game_type_menu_nametable_extra: ; RLE
-        .incbin "nametables/game_type_menu_nametable_extra.bin"
+; game_type_menu_nametable: ; RLE
+;         .incbin "nametables/game_type_menu_nametable_practise.bin"
+; game_type_menu_nametable_extra: ; RLE
+;         .incbin "nametables/game_type_menu_nametable_extra.bin"
 level_menu_nametable: ; RLE
         .incbin "nametables/level_menu_nametable_practise.bin"
 game_nametable: ; RLE
@@ -12,9 +12,27 @@ rocket_nametable: ; RLE
         .incbin "nametables/rocket_nametable.bin"
 legal_nametable: ; RLE
         .incbin "nametables/legal_nametable.bin"
+
+
+
+; added for timing test
+legal_nametable_patch: ; stripe
+        .byte $21, $69, $5, "LEGAL"
+        .byte $21, $89, $9, "GAMEMODE0"
+        .byte $FF
+
+; modified for timing test
 title_nametable_patch: ; stripe
-        .byte $21, $69, $5, $1D, $12, $1D, $15, $E
+        .byte $21, $69, $5, "TITLE"
+        .byte $21, $89, $9, "GAMEMODE1"
+        .byte $FF
+
+; blank tile + MENU, temporary for timing test framework
+menu_nametable_patch: ; stripe
+        .byte $21, $69, $5, "MENU", $FF
+        .byte $21, $89, $9, "GAMEMODE2"
         .byte $FF
+
 rocket_nametable_patch: ; stripe
         .byte $20, $83, 5, $19, $1B, $E, $1c, $1c
         .byte $20, $A3, 5, $1c, $1d, $a, $1b, $1d
diff --git a/src/nmi/render.asm b/src/nmi/render.asm
index 1858e84d..8f981f87 100644
--- a/src/nmi/render.asm
+++ b/src/nmi/render.asm
@@ -1,5 +1,5 @@
 render: branchTo renderMode, \
-            render_mode_static, \
+            render_mode_0, \
             render_mode_scroll, \
             render_mode_congratulations_screen, \
             render_mode_play_and_demo, \
diff --git a/src/ram.asm b/src/ram.asm
index 4015c984..4fedf22e 100644
--- a/src/ram.asm
+++ b/src/ram.asm
@@ -15,7 +15,8 @@ cycleCount: .res 2 ; $0012 ; 2 bytes ; used for crash
 oneThirdPRNG: .res 1 ; $0014 ; used for crash
     .res $2
 
-rng_seed: .res 2 ; $0017
+rng_seed: .res 1 ; $0017
+rng_seed_hi: .res 1;
 spawnID: .res 1 ; $0019
 spawnCount: .res 1 ; $001A
 pointerAddr: .res 2 ; $001B ; used in debug, harddrop
@@ -102,7 +103,8 @@ positionValidTmp: .res 1 ; $00AD              ; 0-level, 1-height
 originalY: .res 1 ; $00AE
 dropSpeed: .res 1 ; $00AF
 tmpCurrentPiece: .res 1 ; $00B0                    ; Only used as a temporary
-frameCounter: .res 2 ; $00B1
+frameCounter: .res 1 ; $00B1
+frameCounterHi: .res 1
 oamStagingLength: .res 1 ; $00B3
     .res 1
 newlyPressedButtons: .res 1 ; $00B5                 ; Active player's buttons
diff --git a/tests/Cargo.lock b/tests/Cargo.lock
index a4cffd9d..e2574d7b 100644
--- a/tests/Cargo.lock
+++ b/tests/Cargo.lock
@@ -2,6 +2,15 @@
 # It is not intended for manual editing.
 version = 4
 
+[[package]]
+name = "aho-corasick"
+version = "1.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ddd31a130427c27518df266943a5308ed92d4b226cc639f5a8f1002816174301"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "autocfg"
 version = "1.1.0"
@@ -95,6 +104,17 @@ version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "25cbce373ec4653f1a01a31e8a5e5ec0c622dc27ff9c4e6606eefef5cbbed4a5"
 
+[[package]]
+name = "filedescriptor"
+version = "0.8.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e40758ed24c9b2eeb76c35fb0aebc66c626084edd827e07e1552279814c6682d"
+dependencies = [
+ "libc",
+ "thiserror",
+ "winapi",
+]
+
 [[package]]
 name = "flips"
 version = "0.2.1"
@@ -205,6 +225,16 @@ dependencies = [
  "slab",
 ]
 
+[[package]]
+name = "gag"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a713bee13966e9fbffdf7193af71d54a6b35a0bb34997cd6c9519ebeb5005972"
+dependencies = [
+ "filedescriptor",
+ "tempfile",
+]
+
 [[package]]
 name = "gumdrop"
 version = "0.8.1"
@@ -231,9 +261,11 @@ version = "0.1.0"
 dependencies = [
  "flips",
  "flips-sys",
+ "gag",
  "gumdrop",
  "md5",
  "minifb",
+ "regex",
  "rustico-core",
 ]
 
@@ -455,6 +487,35 @@ dependencies = [
  "bitflags 1.3.2",
 ]
 
+[[package]]
+name = "regex"
+version = "1.12.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e10754a14b9137dd7b1e3e5b0493cc9171fdd105e0ab477f51b72e7f3ac0e276"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e1dd4122fc1595e8162618945476892eefca7b88c52820e74af6262213cae8f"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc897dd8d9e8bd1ed8cdad82b5966c3e0ecae09fb1907d58efaa013543185d0a"
+
 [[package]]
 name = "rustico-core"
 version = "0.2.0"
@@ -590,6 +651,26 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "thiserror"
+version = "1.0.55"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e3de26b0965292219b4287ff031fcba86837900fe9cd2b34ea8ad893c0953d2"
+dependencies = [
+ "thiserror-impl",
+]
+
+[[package]]
+name = "thiserror-impl"
+version = "1.0.55"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "268026685b2be38d7103e9e507c938a1fcb3d7e6eb15e87870b617bf37b6d581"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.43",
+]
+
 [[package]]
 name = "unicode-ident"
 version = "1.0.12"
diff --git a/tests/Cargo.toml b/tests/Cargo.toml
index 9f2f3c32..ec0121d5 100644
--- a/tests/Cargo.toml
+++ b/tests/Cargo.toml
@@ -7,6 +7,8 @@ edition = "2021"
 gumdrop = "0.8.1"
 rustico-core = { git = "https://github.com/zeta0134/rustico.git", rev = "d31d380b1e15bf7cc80e8827730e56a6df77ae46" }
 minifb = "0.27"
+gag = "1.0.0"
+regex = "1.12.3"
 
 # for patch testing
 flips = "0.2.1"
diff --git a/tests/src/main.rs b/tests/src/main.rs
index c47905fd..df88c6ca 100644
--- a/tests/src/main.rs
+++ b/tests/src/main.rs
@@ -15,6 +15,7 @@ mod garbage;
 mod harddrop;
 mod mapper;
 mod palettes;
+mod parity;
 mod pushdown;
 mod rng;
 mod score;
@@ -26,12 +27,31 @@ mod nmi;
 mod constants;
 mod patch;
 
+use std::path::PathBuf;
 use gumdrop::Options;
 
 fn parse_hex(s: &str) -> Result<u32, std::num::ParseIntError> {
     u32::from_str_radix(s, 16)
 }
 
+#[derive(Debug, Options)]
+enum Command {
+    #[options(help = "run parity tests against vanilla rom")]
+    Parity(ParityOptions),
+}
+
+#[derive(Debug, Options)]
+struct ParityOptions {
+    #[options(help = ".fm2 file", free)]
+    tasfile: PathBuf,
+    #[options(help = "Write logfiles")]
+    write: bool,
+    #[options(help = "Be printy")]
+    verbose: bool,
+    #[options(help = "Show video")]
+    render: bool,
+}
+
 #[derive(Debug, Options)]
 struct TestOptions {
     help: bool,
@@ -52,6 +72,8 @@ struct TestOptions {
     #[options(help = "list drought mode probabilities")]
     drought_probs: bool,
     foo: bool,
+    #[options(command)]
+    command: Option<Command>,
 }
 
 fn main() {
@@ -77,6 +99,22 @@ fn main() {
         ("harddrop", harddrop::test),
     ];
 
+    match options.command {
+        None => {}
+        Some(Command::Parity(ref opts)) => {
+            if *opts.tasfile == *"" {
+                println!("tas file required!");
+                return;
+            }
+            parity::compare(
+                &opts.tasfile,
+                &opts.write,
+                &opts.verbose,
+                &opts.render,
+            )
+        }
+    }
+
     // run tests
     if options.test {
         tests.iter().for_each(|(name, test)| {
diff --git a/tests/src/nmi.rs b/tests/src/nmi.rs
index eca1d6f1..37650688 100644
--- a/tests/src/nmi.rs
+++ b/tests/src/nmi.rs
@@ -7,7 +7,7 @@ pub fn test() {
     let main_loop = labels::get("mainLoop");
     let game_mode = labels::get("gameMode") as usize;
     let level_number = labels::get("levelNumber") as usize;
-    let nmi_label = labels::get("nmi");
+    let _nmi_label = labels::get("nmi");
     let hz_flag = labels::get("hzFlag") as usize;
     let render_flags = labels::get("renderFlags") as usize;
 
diff --git a/tests/src/parity.rs b/tests/src/parity.rs
new file mode 100644
index 00000000..3c071517
--- /dev/null
+++ b/tests/src/parity.rs
@@ -0,0 +1,249 @@
+use regex::Regex;
+use rustico_core::nes::NesState;
+use std::fs::read_to_string;
+use std::fs::File;
+use std::io::BufWriter;
+use std::io::Result;
+use std::io::Write;
+use std::io::stdout;
+use std::path::PathBuf;
+
+use gag::Gag;
+
+use crate::labels;
+use crate::util;
+use crate::video;
+
+static EXTRA_FRAMES: usize = 10;
+static FAILURE_LOG_FRAMES: usize = 100;
+static COMPARE_BYTES: &[&str] = &[
+    "rng_seed",
+    "rng_seed_hi",
+    "frameCounter",
+    "frameCounterHi",
+    "gameMode",
+    "autorepeatX",
+    "spawnCount",
+];
+
+pub fn compare(tasfile: &PathBuf, write: &bool, verbose: &bool, render: &bool) {
+    // println!("{:?} {:?}", tasfile, write,);
+    let tas_buttons = get_buttons_from_tasfile(tasfile, verbose);
+
+    if *write {
+        let (vanilla, gym) = run_tas_and_compare(&tas_buttons, verbose, &render);
+        let _ = write_bytes_to_file(&get_new_filename(tasfile, "clean"), &vanilla);
+        let _ = write_bytes_to_file(&get_new_filename(tasfile, "gym"), &gym);
+    } else {
+        print!(">> comparing results for {tasfile:?}... ");
+        stdout().flush().unwrap();
+        let vanilla_logfile = get_new_filename(tasfile, "clean");
+        let compare_bytes: Vec<u8> = read_bytes_from_file(&vanilla_logfile);
+        compare_with_vanilla(&tas_buttons, &compare_bytes, &verbose, &render);
+        println!(" ✅");
+    }
+}
+
+struct OptionalVideo {
+    video: Option<video::Video>,
+}
+
+impl OptionalVideo {
+    fn new(render: &bool) -> Self {
+        let video = if *render {
+            Some(video::Video::new())
+        } else {
+            None
+        };
+
+        Self { video }
+    }
+    fn set_position(&mut self, x: isize, y: isize) {
+        if let Some(video) = &mut self.video {
+            video.window.set_position(x, y);
+        }
+    }
+    fn render(&mut self, emu: &mut rustico_core::nes::NesState) {
+        if let Some(video) = &mut self.video {
+            video.render(emu);
+        }
+    }
+}
+
+fn read_bytes_from_file(filename: &PathBuf) -> Vec<u8> {
+    let mut result = Vec::new();
+
+    for line in read_to_string(filename).unwrap().lines() {
+        for byte in line.split_whitespace() {
+            result.push(u8::from_str_radix(byte, 16).unwrap())
+        }
+    }
+
+    result
+}
+
+fn write_bytes_to_file(filename: &PathBuf, bytes: &Vec<u8>) -> Result<()> {
+    let file = File::create(filename)?;
+    let mut writer = BufWriter::new(file);
+
+    for chunk in bytes.chunks(COMPARE_BYTES.len()) {
+        for (i, b) in chunk.iter().enumerate() {
+            if i > 0 {
+                write!(writer, " ")?;
+            }
+            write!(writer, "{:02X}", b)?;
+        }
+        writeln!(writer)?;
+    }
+    Ok(())
+}
+
+fn get_new_filename(filename: &PathBuf, suffix: &str) -> PathBuf {
+    let stem = filename.file_stem().unwrap();
+    let mut name = stem.to_os_string();
+    name.push(format!("-{}.log", suffix));
+    filename.with_file_name(name)
+}
+
+fn extract_values_from_labels(emu: &mut NesState) -> Vec<u8> {
+    let mut result: Vec<u8> = Vec::new();
+    for label in COMPARE_BYTES {
+        let addr = labels::get(label) as usize;
+        let value = emu.memory.iram_raw[addr];
+        result.push(value)
+    }
+
+    return result;
+}
+
+fn compare_with_vanilla(
+    tas_buttons: &Vec<u8>,
+    compare_bytes: &Vec<u8>,
+    _verbose: &bool,
+    render: &bool,
+) {
+    let mut gym;
+    {
+        let _print_gag = Gag::stdout().unwrap();
+        gym = util::emulator(None);
+    }
+    let mut ptr = 0;
+    let mut view = OptionalVideo::new(render);
+    for (i, buttons) in tas_buttons.into_iter().enumerate() {
+        let expected = &compare_bytes[ptr..ptr + COMPARE_BYTES.len()];
+        ptr += COMPARE_BYTES.len();
+        let values = extract_values_from_labels(&mut gym);
+        if expected != values {
+            eprintln!("❌");
+            eprintln!("Gym: {:?}", values);
+            eprintln!("Vog: {:?}", expected);
+            panic!("Mismatch on line {}!", i + 1);
+        }
+
+        gym.run_until_vblank();
+        util::set_controller_emu_native(&mut gym, *buttons);
+        view.render(&mut gym);
+    }
+}
+fn run_tas_and_compare(tas_buttons: &Vec<u8>, verbose: &bool, render: &bool) -> (Vec<u8>, Vec<u8>) {
+    let mut og;
+    let mut gym;
+    {
+        // suppress rustico's output when loading roms
+        let _print_gag = Gag::stdout().unwrap();
+        og = util::emulator(Some(util::OG_ROM));
+        gym = util::emulator(None);
+    }
+    let mut og_bytes = Vec::new();
+    let mut gym_bytes = Vec::new();
+    let mut vanilla_view = OptionalVideo::new(render);
+    let mut gym_view = OptionalVideo::new(render);
+    let mut fail_frames: usize = 0;
+    gym_view.set_position(512, 30);
+    for buttons in tas_buttons.iter() {
+        if fail_frames > FAILURE_LOG_FRAMES {
+            break;
+        }
+        let gym_values = extract_values_from_labels(&mut gym);
+        gym_bytes.extend(gym_values.clone());
+
+        let og_values = extract_values_from_labels(&mut og);
+        og_bytes.extend(og_values.clone());
+
+        if gym_values.as_slice() != og_values.as_slice() {
+            fail_frames += 1;
+        }
+
+        if *verbose {
+            println!("OG: {:?}", og_values);
+            println!("Gym: {:?}", gym_values);
+        }
+
+        og.run_until_vblank();
+        gym.run_until_vblank();
+        util::set_controller_emu_native(&mut og, *buttons);
+        util::set_controller_emu_native(&mut gym, *buttons);
+        vanilla_view.render(&mut og);
+        gym_view.render(&mut gym);
+    }
+
+    return (og_bytes, gym_bytes);
+}
+
+fn get_buttons_from_tasfile(filename: &PathBuf, verbose: &bool) -> Vec<u8> {
+    let contents = read_to_string(filename).expect("can't open tasfile");
+
+    // let reader = BufReader::new(file);
+    let mut tas_buttons: Vec<u8> = Vec::new();
+    let tas_line =
+        //     RLDUTSBA
+        Regex::new(r"(?m)^\|0\|([R.])([L.])([D.])([U.])([T.])([S.])([B.])([A.])\|\|\|").unwrap();
+
+    for (i, (_, [right, left, down, up, start, select, b, a])) in tas_line
+        .captures_iter(&contents)
+        .map(|c| c.extract())
+        .enumerate()
+    {
+        // helps line things up
+        if i < 2 {
+            continue;
+        }
+        let mut button: u8 = 0;
+        if right == "R" {
+            button |= 0x80 // input::RIGHT 0x01
+        }
+        if left == "L" {
+            button |= 0x40 // input::LEFT 0x02
+        }
+        if down == "D" {
+            button |= 0x20 // input::DOWN 0x04
+        }
+        if up == "U" {
+            button |= 0x10 // input::UP 0x08
+        }
+        if start == "T" {
+            button |= 0x08 // input::START 0x10
+        }
+        if select == "S" {
+            button |= 0x04 // input::SELECT 0x20
+        }
+        if b == "B" {
+            button |= 0x02 // input::B 0x40
+        }
+        if a == "A" {
+            button |= 0x01 // input::A 0x80
+        }
+        tas_buttons.push(button);
+
+        if *verbose {
+            eprintln!(
+                "{:?} {:?} {:?} {:?} {:?} {:?} {:?} {:?} {:08b}",
+                right, left, down, up, start, select, a, b, button,
+            );
+        }
+    }
+    for _ in 0..EXTRA_FRAMES {
+        tas_buttons.push(0);
+    }
+    return tas_buttons;
+}
diff --git a/tests/src/tspins.rs b/tests/src/tspins.rs
index 6029f11e..098d2346 100644
--- a/tests/src/tspins.rs
+++ b/tests/src/tspins.rs
@@ -3,7 +3,7 @@ use crate::{util, labels, playfield};
 pub fn test() {
     let mut emu = util::emulator(None);
 
-    for _ in 0..4 {
+    for _ in 0..6 {
         emu.run_until_vblank();
     }
 
diff --git a/tests/src/util.rs b/tests/src/util.rs
index a27fe0de..279ed0dc 100644
--- a/tests/src/util.rs
+++ b/tests/src/util.rs
@@ -35,6 +35,10 @@ pub fn set_controller_raw(emu: &mut NesState, buttons: u8) {
     emu.p1_input = flipped_buttons;
 }
 
+pub fn set_controller_emu_native(emu: &mut NesState, buttons: u8) {
+    emu.p1_input = buttons;
+}
+
 pub fn set_controller(emu: &mut NesState, button: char) {
     set_controller_raw(emu, match button {
         'L' => input::LEFT,
diff --git a/testtas.sh b/testtas.sh
new file mode 100755
index 00000000..9590fe77
--- /dev/null
+++ b/testtas.sh
@@ -0,0 +1,12 @@
+#!/usr/bin/env bash
+
+cargo build --release --manifest-path tests/Cargo.toml
+
+node build.js
+
+while read -r -d '' tas; do
+    clean="${tas%.*}"-clean.log
+    if test -f "$clean"; then
+        ./tests/target/release/gym-tests parity "$tas"
+    fi
+done < <(find tases/ -name "*.fm2" -print0)
diff --git a/tools/log.lua b/tools/log.lua
new file mode 100644
index 00000000..bc64745c
--- /dev/null
+++ b/tools/log.lua
@@ -0,0 +1,127 @@
+-- line up with parity.rs indexing
+-- frameCount starts at 2
+local OFFSET = -2
+
+-- local TEST_LENGTH = 1794
+-- local START_FRAMES = {265, 270, 274, 286}
+local TEST_LENGTH = 10000
+local START_FRAMES = {265}
+-- local START_FRAMES = {}
+
+local BREAK_FRAME = nil
+
+local COMPARE = true
+
+local rom = emu.getRomInfo()
+local romPath, _ = string.gsub(rom.path, rom.name, "")
+local filename = rom.name:gsub("%.%w+$", "") .. ".log"
+local path = string.gsub(rom.path, rom.name, filename)
+
+emu.log("Opening " .. path)
+local original_results = {}
+local file
+if COMPARE then
+    local og_path = string.gsub(rom.path, rom.name, "clean.log")
+    for line in io.lines(og_path) do
+        line_nos = {}
+        for num in string.gmatch(line, "%S+") do
+            table.insert(line_nos, num)
+        end
+        table.insert(
+            original_results,
+            {
+                tonumber(line_nos[2], 16),
+                tonumber(line_nos[3], 16),
+                tonumber(line_nos[4], 16)
+            })
+    end
+    emu.log("Comparing.  Loaded " .. #original_results .. " lines")
+end
+local file = io.open(path, "w")
+-- workaround to get a global state
+local startIdx = {1}
+local cmpIdx = {1}
+
+
+function logFrame()
+    state = emu.getState()
+    local frameCount = state.frameCount + OFFSET
+
+    if BREAK_FRAME == frameCount then
+        emu.breakExecution()
+    end
+
+    if startIdx[1] < #START_FRAMES + 1 then
+        if frameCount == START_FRAMES[startIdx[1]] then
+            emu.log(string.format("%04d", frameCount) .. " pressing start")
+            emu.setInput({start = true})
+            startIdx[1] = startIdx[1] + 1
+        end
+    end
+
+    local rng_seed = valueAtLabel16('rng_seed')
+    local frameCounter = valueAtLabel16('frameCounter')
+    local gameMode = valueAtLabel('gameMode')
+    local generalCounter = valueAtLabel('generalCounter')
+    local sleepCounter = valueAtLabel('sleepCounter')
+
+    if COMPARE then
+        if not original_results[cmpIdx[1]] then
+            emu.log("Ran out of frames to compare")
+            emu.breakExecution()
+            return
+        end
+        expected_rng = original_results[cmpIdx[1]][1]
+        expected_fc = original_results[cmpIdx[1]][2]
+        expected_gm = original_results[cmpIdx[1]][3]
+        cmpIdx[1] = cmpIdx[1] + 1
+
+        if (
+            expected_rng ~= rng_seed or
+            expected_fc & 0xFF ~= frameCounter & 0xFF -- or
+            -- expected_gm ~= gameMode
+        ) then
+        emu.log(
+            "Expect: "
+            .. string.format("%04X", expected_rng) .. " "
+            .. string.format("%04X", expected_fc) .. " "
+            .. string.format("%02X", expected_gm)
+        )
+        emu.log(
+            "Actual: "
+            .. string.format("%04X", rng_seed) .. " "
+            .. string.format("%04X", frameCounter) .. " "
+            .. string.format("%02X", gameMode)
+        )
+            emu.breakExecution()
+        end
+    else
+
+        file:write(
+            string.format("%04d", frameCount) .. " "
+            .. string.format("%04X", rng_seed) .. " "
+            .. string.format("%04X", frameCounter) .. " "
+            -- .. string.format("%02X", sleepCounter) .. " "
+            -- .. string.format("%02X", generalCounter) .. " "
+            .. string.format("%02X", gameMode) .. "\n"
+        )
+
+        if frameCount >= TEST_LENGTH then
+            file:close()
+            emu.breakExecution()
+            emu.log("Wrote " .. frameCount + 1 .. " lines to " .. path)
+        end
+    end
+end
+
+function valueAtLabel(label)
+    local addr = emu.getLabelAddress(label)
+    return emu.read(addr.address, addr.memType)
+end
+
+function valueAtLabel16(label)
+    local addr = emu.getLabelAddress(label)
+    return emu.read16(addr.address, addr.memType)
+end
+
+emu.addEventCallback(logFrame, emu.eventType.inputPolled);
diff --git a/tools/tas.lua b/tools/tas.lua
new file mode 100644
index 00000000..ac2b61cd
--- /dev/null
+++ b/tools/tas.lua
@@ -0,0 +1,110 @@
+-- https://tasvideos.org/7625S
+-- local TASFILE = "tases/r57shell-Archanfel-Tetris-fastest999999.fm2"
+local TASFILE = "tases/start-pattern-a.fm2"
+
+local rom = emu.getRomInfo()
+local romPath, _ = string.gsub(rom.path, rom.name, "")
+local tasFile =  romPath .. TASFILE
+local compareFile = tasFile:gsub("%.%w+$", "") .. "-clean.log"
+
+local COMPARE_BYTES = {
+    "rng_seed",
+    "rng_seed_hi",
+    "frameCounter",
+    "frameCounterHi",
+    "gameMode",
+    "autorepeatX",
+    "spawnCount",
+}
+
+local cmpIdx = {1 + #COMPARE_BYTES} -- skip a frame to line things up
+
+local inputs = {}
+for line in io.lines(tasFile) do
+    local buttons = line:match("^|0|(........)|||$")
+    if buttons then
+        local input = {}
+        local mapped = {
+             "right",
+             "left",
+             "down",
+             "up",
+             "start",
+             "select",
+             "b",
+             "a",
+        }
+        for i = 1, 8 do
+            input[mapped[i]] = not (buttons:sub(i, i) == ".")
+        end
+        table.insert(inputs, input)
+    end
+end
+
+-- extra input to force extra frame (so last input is processed)
+table.insert(inputs, {})
+
+local compareBytes = {}
+for line in io.lines(compareFile) do
+    for num in string.gmatch(line, "%S+") do
+        table.insert(compareBytes, tonumber(num, 16))
+    end
+end
+
+
+function applyInputs()
+    local state = emu.getState()
+    local input = inputs[state["frameCount"] + 1]
+    if not input then
+        emu.breakExecution()
+        return
+    else
+        emu.setInput(input)
+    end
+    local expect = slice(compareBytes, cmpIdx[1], cmpIdx[1] + #COMPARE_BYTES)
+    local actual = getValuesFromLabels()
+
+    local expectStr = getHexString(expect)
+    local actualStr = getHexString(actual)
+    if expectStr ~= actualStr then
+            emu.log("Expect: " .. expectStr)
+            emu.log("Actual: " .. actualStr)
+            emu.breakExecution()
+    end
+    cmpIdx[1] = cmpIdx[1] + #COMPARE_BYTES
+end
+
+function getHexString(numbers)
+    result = {}
+    for _, number in ipairs(numbers) do
+        table.insert(result, string.format("%02X", number))
+    end
+    return table.concat(result, " ")
+
+end
+
+function slice(values, i, n)
+    local result = {}
+    local idx = i
+    while idx < n do
+        table.insert(result, values[idx])
+        idx = idx + 1
+    end
+    return result
+end
+
+function getValuesFromLabels()
+    local result = {}
+    for _, label in ipairs(COMPARE_BYTES) do
+        local value = valueAtLabel(label)
+       table.insert(result, value )
+    end
+    return result
+end
+
+function valueAtLabel(label)
+    local addr = emu.getLabelAddress(label)
+    return emu.read(addr.address, addr.memType)
+end
+
+emu.addEventCallback(applyInputs, emu.eventType.inputPolled);