This is the code i used,
void extint(void) __irq ; void main() { PINSEL0 = 0X0000000C; //selecting EXT0 IODIR0 = 0x0000ff00; VICVectCntl0 = 0x0000002E; VICVectAddr0 = (unsigned long)extint; VICIntEnable = 0x00004000; IODIR0 = 0x00ff0000; while(1) { IOSET0 = 0x00ff0000; IOCLR0 = 0x00ff0000; } } void extint(void) __irq { IOSET0 = 0x0000ff00; EXTINT = 0x00000001; VICVectAddr = 0; }
it compiles. but when I run it on the simulation it does not enters in to the ISR function.
when I checked it on debug mode, the 'int' bit in EINTO is getting set and the VICVectAddr
also updated with the address of VICVectAddr0.
I used an example and it worked fine.
In the disassembly, in the address 0x00000018"LDR PC, [PC, #-0x0FF0]"
Are you aware about the assembler code in the startup file? It contains mappings for the interrupt vector table.
In the Example code, the disassembler start address 0x00000000 contains the label 'Vectors'
"Vectors LDR PC, Reset_Addr"
which is the reset address.
In the project which I created the start address 0x00000000 contains the label, '__main'
why the this is not starts from the label, 'Vectors'.
what I am asking is , should I have to change any configuration to get it load from the Vectors.
if it loads from the label 'Vector', I think the ISR function will get executed.
Thank you for the reply.
Do you have a startup file in your project?
A normal project would link with the startup file starting from address zero, getting the reset vector first in memory. Only when doing advanced programming (like running on a system that has a boot loader) could it be relevant with a different address for the vector table.
It has the startUp file included while the project creating.
and I just tried the code in simulation.
I thought I missed some basic thing, which is faced by some people.
Thankyou,
My problem got solved.
if someone have the same problem follow this.
Project -> option for target -> Linker -> select the checkbox "Use Memory Layout From Target Dialog"