I understand that as an interrupt can occur at any time that stack and any processor registers must be returned to the state at the beginning of the interrupt, to allow normal execution to resume.
So if I intent to simply call a C function from an interrupt I need to manually store d0-d1/a0-a1 and ...
Search found 5 matches
- Mon Jul 23, 2012 7:19 am
- Forum: Megadrive/Genesis
- Topic: Using redirection vector table to jump interrupts to C func
- Replies: 6
- Views: 5894
- Mon Jul 23, 2012 12:04 am
- Forum: Megadrive/Genesis
- Topic: Using redirection vector table to jump interrupts to C func
- Replies: 6
- Views: 5894
Thanks Chilly, I see my error now. I was confused that the sample code seemed to provide redirection vectors but did not actually use them.
So my basic error was that a C code will automatically store and recover volatile processor registers (d0-d1/a0-a1). However in a ASM function it is up to the ...
So my basic error was that a C code will automatically store and recover volatile processor registers (d0-d1/a0-a1). However in a ASM function it is up to the ...
- Sun Jul 22, 2012 10:29 pm
- Forum: Megadrive/Genesis
- Topic: Using redirection vector table to jump interrupts to C func
- Replies: 6
- Views: 5894
Using redirection vector table to jump interrupts to C func
Hi I am working with the TicTacToe C code sample to begin learning a little more about the lower levels of the system.
I understand that the interrupt vectors like vblank are fixed in ROM. The standard way of getting round this (as I understand) is storing a redirection vector table in RAM. Then ...
I understand that the interrupt vectors like vblank are fixed in ROM. The standard way of getting round this (as I understand) is storing a redirection vector table in RAM. Then ...
- Wed Jul 18, 2012 6:43 pm
- Forum: Tools
- Topic: Update your Genesis/32X Toolchain!
- Replies: 110
- Views: 207847
- Wed Jul 18, 2012 2:17 pm
- Forum: Tools
- Topic: Update your Genesis/32X Toolchain!
- Replies: 110
- Views: 207847