At the title screen, press C, C, Up, Down, Down, Down, Down, Up. There could be any amount of C's, but a minimum of 2, and they can be positioned anywhere, except at the end of the code.
SCORE - The top line shows your position on the screen (every 1 pixel). Every digit is a bit, two digits are a byte, four are a word, and eight are a Dword. The left most word on the top row gives your X axis (horizontal) position on the grid. The right most word gives you your Y axis (vertical) position on the grid. For the bottom row, the left most word acts as what TIME would act like in a normal game, upping the number every second, except it's in hexadecimal. The right most word is a timing clock, cycling from 0000 to 0080 and then from 0080 to 0000 and so on. This cycling clock is used for timing objects such as swaying platforms, water movement, and etc.
TIME - Displays how many sprites are on the screen at once. This number shouldn't surpass 80.
RINGS - Displays your ring count.
B - Toggle Debug On
Debug Toggled On
A - Move Forward in Object Cycle
B - Toggle Debug Off
C - Place Object on Screen
A + C - Move Backward in Object Cycle
To toggle debug in a level, make sure the code is on, and hold A and press start to enter the level with debug. This carries over from level to level.
To toggle 2P interlaced mode, make sure the debug code is on, and hold B and press start to enter the level with 2P interlaced mode. Note: This will not work with levels where there is water (or "Mega-Mack") This doesn't carry over from level to level.
To toggle the Video Display Processor's shadowing and highlighting feature, which some call Night Mode, make sure the debug code is enabled and hold C and press start to enter the level. This doesn't carry over from level to level.
Note: When exiting a stage through egg container or end signpost, you may trigger debug if it's not triggered, 2P interlace, or "Night Mode" by holding their respective buttons after the results for the level are calculated.
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