Hi!

Iam trying to program an interrupt handler for AT91SAM7S256 (using Keil ARM compiler). I read some example codes and i don't know why we need an assembly interrupt handler with a C interrupt hander. In this assembly interrupt handler i can understand that these codes are for saving and restoring some registers and change priviledged mode also.

My question is when we have to write an assembly interrupt handler accompany with a C interrupt handler?