vectors.s

来自「专业汽车级嵌入式操作系统OSEK的源代码」· S 代码 · 共 34 行

@  This is the vector set up for an AT91SAM7

	.text
	.code 32
	.align 	0
	
@ This is not actally executed in this code stream. Instead it is
@ copied into the reloacted vector space.
@ NB When executing the first instruction in an abort/interrupt, the pc is 8 (ie 2 instructions)
@ ahead of the start of instruction being executed.
@ Hence,  for the first 6 vectors, the ldr loads the correct address into pc by looking at pc + 0x18.
@
@ For the IRQ and FIQ, we subtract 0xF20 to get to the vectors held in the AIC.
@
@ NB We do not do branches because these would get screwed up by relocation.
@


	    ldr   pc,v0	 	 	@ reset vector
            ldr   pc,v1	  		@ Undefined Instruction
            ldr   pc,v2	 	 	@ Software Interrupt
            ldr   pc,v3	  		@ Prefetch Abort
            ldr   pc,v4		  	@ Data Abort
            ldr   pc,v5		  	@ reserved
	    ldr   pc,[pc,#-0xF20]	@ IRQ : read the AIC
	    ldr   pc,[pc,#-0xF24]	@ FIQ : read the AIC
v0:	    .long start
v1:	    .long undef_handler
v2:         .long swi_handler
v3:         .long prefetch_abort_handler
v4:	    .long data_abort_handler
v5:	    .long reserved_handler