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Coding > Official games use a CRT with interrupt handler?

#143209 - Dwedit - Thu Oct 18, 2007 6:59 am

I was just noticing that official GBA games contain code (located at address 080000E0) which installs an interrupt handler pointing to address 080000FC. From there, there is a standardized interrupt handler. Most games replace the default interrupt handler with their own, but some games actually use that ROM interrupt handler.

So what are the pros and cons to having an interrupt handler in the CRT?
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#143210 - eKid - Thu Oct 18, 2007 7:13 am

Pros:
Easy, interrupt handlers can be a bit of a pain to write
Cons:
You wont have full control over interrupts if you use a standard version (some games may want to change priorities/take special action for certain interrupts)