Insector X (Genesis)

This page is rather stubbly and could use some expansion. Are you a bad enough dude to rescue this article?

It's like if Ant Man waged a war on all insects, and the insects armed themselves with laser cannons. Has a much cuter counterpart over on the Famicom and Arcade.

Dummied-Out Controller 2 Functionality#

Sega's stock Genesis controller input code looks something like this:

    lea    (SomeAddress).l,a0
    lea    ($A10003).l,a1
    bsr.s  ReadController
    addq.w #2,a1
ReadController:
    ; ...

The buttons for Controller 1 are read into SomeAddress and SomeAddress + 1, and the buttons for Controller 2 into SomeAddress + 2 and SomeAddress + 3.

Insector X changes this to:

    lea    (SomeAddress).l,a0
    lea    ($A10003).l,a1
    bsr.s  ReadController
    rts
    addq.w #2,a1
ReadController:
    ; ...

Note the inserted rts instruction. This will cause the game to not read Controller 2 at all. As it turns out, there are a few buttons on Controller 2 that are checked during the game. But that rts makes sure those buttons never actually do anything!

To re-enable the deleted functionality, nop out the rts with code 00059A:4E71. This works with both ROMs.

The button codes are simple:

• Press 2P Start at any time during a stage to skip to the next one. If paused, this will happen when you unpause.
• Press 2P A at any time during a stage (except when paused) to increase your weapon's shot power by 1 each press; it will wrap back to the lowest power level after you reach max power.
• Press 2P B at any time during a stage (except when paused) to give yourself both bomb weapon choices. Each press will change which effect the two bombs will have.

This needs some investigation. Discuss ideas and findings on the talk page. Specifically: Are there other codes?

References#