10. interrupts

#include< LPC21xx.h> 

void enable_interrupts(void) {

__asm {

MRS RO, CPSR // Move the current program status register to RO 

BIC RO, RO, #0x80 // Clear the I bit in CPSR (enables IRQ) 

MSR CPSR_C, RO // Move the modified value back to CPSR

}

}

void disable_interrupts(void) {

__asm {

MRS RO, CPSR // Move the current program status register to RO

 ORR RO, RO, #0x80 // Set the I bit in CPSR (disables IRQ) 

MSR CPSR_c, RO // Move the modified value back to CPSR

}

}

int main (void) {

disable_interrupts(); // Disable interrupts

enable_interrupts(); // Enable interrupts

}

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