Find this resource on GitHub. No further updates will be made here.


This asm/patch adds a crash handler routine that provides a dump of the stack and registers on screen. It runs whenever a BRK or COP instruction is encountered, or when SM jumps to its own crash routine, which is normally a simple "jump-to-self" loop.

The GitHub repository includes the ASM code, 2bpp graphics (mostly font), and everything needed to build an IPS patch or patch a ROM directly. CrashHandler.asm has a few defines at the top for configuring the patch.

With "EXTRA_PAGES" enabled, multiple pages will be available to scroll through in the crash screen. A memory viewer is provided for checking any address in CPU memory (including ROM space). A third page is left mostly blank, intended for the hack author to provide instructions to players for reporting bugs, or to display memory addresses of interest.

It uses less than 200h bytes in bank $80, and 600-A00h bytes of code depending on the EXTRA_PAGES setting. There's also A00h bytes of graphics and 100-200h of text strings. The code needs to be somewhere in banks $80-BF, but the rest can live anywhere in the ROM.

If you have any suggestions or feedback, please let me know on the MetConst Discord, or on GitHub.