#22607 - sgeos - Fri Jun 25, 2004 4:25 am
Do I need to touch any registers other than IE and IME to enable game pak interrupts?
-Brendan
#22625 - tepples - Fri Jun 25, 2004 4:43 pm
You also need to touch at least the circuitry on the cart's ASIC, which may be mapped into ROM or SRAM. What sort of interrupts do you have in mind? Just the yanked-cart signal?
_________________
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#22627 - sgeos - Fri Jun 25, 2004 5:06 pm
| tepples wrote: |
| What sort of interrupts do you have in mind? Just the yanked-cart signal? |
Just writing an interrupt library. The library's job is to make sure that interrupts are enabled. It doesn't care how they are triggered. SIO is a pain because five registers are involved. Game Pak is odd in that only two are required. (Every other interrupt requires three.)
| tepples wrote: |
| You also need to touch at least the circuitry on the cart's ASIC, which may be mapped into ROM or SRAM. |
Fair enough. Based on how one interperts 'enable'. Has anyone messed around with a cart yank interrupt?
A game pak interrupt is triggered whenever a cart is insert or removed, correct? Do you suppose a game pak interrupt could be used to bypass the need for a valid header on commercial carts? Would it be possible to create a multiboot image that would "mask in" ROM space. After that it enables a game pak interrupt it waits for the headerless unofficial cart.
Of course that would entirely defeat the purpose of a handheld system. If that would work, one would need a preboot cart to properly pull this off. That brings us back to the header issue.
-Brendan
#22949 - caitsith2 - Thu Jul 01, 2004 7:28 pm
Well, I actually found a commercial game, that uses the gamepak interrupt to totally put the system to sleep, if the gamepak gets pulled. The game is Mario Golf: Advance tour.