sysctl dev.ti_pruss.0.irq.2.channel=2 # mapping channel 2 to irq2
sysctl dev.ti_pruss.0.irq.2.event=16 # mapping event 16 to irq2
sysctl dev.ti_pruss.0.irq.2.enable=1 # enable the irq2
sysctl dev.ti_pruss.0.global_interrupt_enable=1 # enable PRU global interrupts

.origin 0
.entrypoint START
START:
ZERO &r0, 120
MOV r31, (1 << 5) 
HALT

pasm -V3 -bL test.p

# -p 0 is pru0, -t ti is type Texas Instruments, -er means enable+reset
pructl -p 0  -t ti -er test.bin

#include <sys/time.h>                                                                                                                                                            
#include <sys/types.h>                                                                                                                                                           
#include <sys/event.h>                      
#include <err.h>                            
#include <fcntl.h>                          
#include <stdio.h>                          
#include <stdlib.h>                         
#include <string.h>                         
#include <unistd.h>                         
#include <signal.h>                         

int main( int argc, char* argv[] )          
{                                           
        int fd;                         

        printf("opening of %s ", argv[1]);  
        fd = open( argv[1], O_RDONLY);      

        if (fd == -1) 
                perror("open");       

        for(;;)                             
        {                                   
                uint64_t time;                      
                while( read(fd, &time, sizeof(time)) > 0 )                              
                {                           
                        printf("=> %llu.%09llu \n", time/1000000000, time%1000000000);  
                }     

        }             
        close(fd);    
        return EXIT_SUCCESS;                
}