How do you get debug mode for sonic 3 and knuckles?

To get debug mode for Sonic 3 and Knuckles, first get level select. To get level select, go to the first zone: Angel Island Zone and hang on the swing stem and press left, left, left, right, right,right,up,up,up. When you finished pressing the buttons you will hear a chime meaning you did the code correctly.

After hearing the chime press pause and then press B, you'll be back at the main screen (Sonic wiggling his finger). Go down twice and you'll see sound test, go to it and voila you can choose a zone! Now to get debug mode, go to level select and go to Mushroom Hill Zone Act 1. Find those metal bars (the bars that you have to press the down button to get up) hang on one and press the same buttons you pressed hanging on the swing stem: left, left, left, right, right,right,up,up,up. You'll hear another chime meaning you did the code correctly. Then press pause and then press B. Then go to level select. When you press the x button you change the number on top of Hydrocity Zone in level select. #00 is Sonic and Tails, #01 Sonic alone, #02 Tails alone, #03 Knuckles. Hold a,b,x buttons and choose a zone. When your in the zone, press a and voila you got debug mode! Press B (when you press a) you can change the item you want to have, if you press b (without pressing a) the gravity will change and you"ll walk upside down. Press B again to change back the gravity. Press x to place the object somewhere. And press a to be sonic again besides an object. If you're playing Sonic Mega Collection for gamecube, the a button is a, b is b, and x is x. If your playing the Genesis emulator on the computer, a is s, b is a, and x is d. Have fun using level select and debug mode : )