monitor_upper = env("MONITOR_UPPER", 0xf615)
monitor_lower = env("MONITOR_LOWER", 0x7349)

monitor = data 0xFFFF
keyboard = data 0xFFFF
clock = data 0xFFFF

main:
    A = 0

def once _detect:
    J = 0
    I = hardware_count()
    while J < I:
        hardware_query(J)
        if A == monitor_upper and B == monitor_lower:
            [monitor] = J
        if A == keyboard_upper and B == keyboard_lower:
            [keyboard] = J
        if A == clock_upper  and B == clock_lower:
            [clock] = J

def display_map_screen:
    A = 0
    _detect()
    hardware_interrupt(monitor)

def display_map_font:
    A = 1
    _detect()
    hardware_interrupt(monitor)

def display_map_palette:
    A = 2
    _detect()
    hardware_interrupt(monitor)

def display_set_border_color:
    A = 3
    _detect()
    hardware_interrupt(monitor)

def display_dump_font:
    A = 4
    _detect()
    hardware_interrupt(monitor)


def display_dump_palette:
    A = 3
    _detect()
    hardware_interrupt(monitor)