Majora's Mask - char_checker_JP

-- char_checker_JP.lua
--
-- Automate the process of checking whether or not a printed
-- character will crash Majora's Mask (J 1.0) on Bizhawk.
-- US verison: https://pastebin.com/WivTk2gN
--
-- Author: @Faschz
-- Created: April 7th, 2019

CHARACTER_ADDR = 0x1CAE00
TEXTBOX_ADDR = 0x3FD51E
TIMER_ADDR = 0x1FA0F3

file = io.open('Character Crashes JP 1.0.txt', 'w')

for c=0, 65535 do
    -- Recover from any crashes by loading a state about to select
    -- the soaring location for Great Bay Coast
    savestate.loadslot(2)

    -- Set the character in the message table
    mainmemory.write_u16_be(CHARACTER_ADDR, c)

    -- Select the soaring location
    joypad.set({["A"] = true}, 1)
    emu.frameadvance()
    joypad.set({["A"] = false}, 1)

    -- Wait until the textbox appears and changes the address
    while c ~= mainmemory.read_u16_be(TEXTBOX_ADDR) do
        emu.frameadvance()
    end

    -- Check if the game is crashed by reading the frame count
    start = mainmemory.readbyte(TIMER_ADDR)
    is_crashed = true

    --3 frames work, but lets be on the safe side
    for frame=0, 5 do
        if start ~= mainmemory.readbyte(TIMER_ADDR) then
            is_crashed = false
            break
        end
        emu.frameadvance()
    end

    if is_crashed then
        print(c)
        file:write(c..'\n')
    end
end

file:write("DONE!")
file:close()


print("DONE!")