NRF9E5 External Interrupt Issue

[Sobakava]

I'm trying to detect external interrupts using NRF9E5 / 8051 core RF transceiver microcontroller. Development environment is Keil C51

At first I was confused with ISR declarations:

void INT0_ISR( void ) interrupt 0 //0x03{

// Ext INT0 handler

}


void INT1_ISR( void ) interrupt 2 //0x13{

// Ext INT1 handler

}


Is that correct?If so, I still can't figure out why I can't detect external interruptsI enabled the interrupt using EX1 bit.


void INT0_ISR( void ) interrupt 0 //0x03{

// Ext INT0 handler

LED ^= 1; // toggle LED

}void INT1_ISR( void ) interrupt 2 //0x13

{

// Ext INT1 handler

LED ^=1; // toggle LED

}

void main ( void ) {

PO_DIR = 0x57; // P07 output P05 LED. Rest is input

EX0 = 1;

EX1 = 1;

EA = 1;

while( 1 ) {

P07=1; delayms(1);

P07=0; delayms(1);

}

}

Using this piece of code, I could never detect the interrupts applied by an external source or micro-switch with pull up resistors connected to P03 and P04.

These pins are configured as inputs. Interrupts are enabled including global interrupt.
I also enabled a timer0 overflow interrupt to test if any interrupt works. It works.

I tried to toggle LED in main loop. It is also OK.

Somehow I can not generate interrupts using INT1 and INT0 pins. I also tried both configurations; level sensitive mode and edge sensitive mode. It does not help too.

Any ideas? Any tested code for this MCU or any other 8051 core microcontorller with INT0_N and INT1_N interrupt inputs?

Regards

 

[Sobakava]

Here is the solution from myself as a future reference to who faces with the same issue:

Nordic replied my support case. The problem was, NRF9E5 INT_0 and INT_1 external interrupts should be configured using P0_ALT register. If P0.3 and P0.4 pins are configured as I/O, they don't generate interrupts. They should be configured as interrupt pins using P0_ALT register.