Creating 2 input captures

I have some trouble creating 2 input captures on a 68HC11 microcontroller board. I can get a signal from PA2/IC1 however, I'm unable to get a signal from PA1/IC2. Whenever I input a signal into IC2, my program terminates. I've looked at my book and examples but I don't see one with 2 input captures. Any help would be appreciated. My code below:

#include <hc11.h>
#include <stdio.h>
unsigned int old_TIC1;
unsigned int old_TIC2;
unsigned int period;
unsigned int period2;
unsigned long int frequency;
unsigned long int frequency2;
#pragma interrupt_handler icisr

void icisr(){
period = TIC1 - old_TIC1;
old_TIC1 = TIC1;
period2 = TIC2 - old_TIC2;
old_TIC2 = TIC2;
TFLG1 = 6;
}

void initialization() {
*(unsigned char * )0xe8 = 0x7e;
*(void(**)())0xe9 = icisr;
TMSK1 = 6; /* enable IC1 & IC2 */
TCTL2 = 0x14; /* configure to capture rising edge of IC1 & IC2*/
asm("cli\n");
}

void calculate(){
frequency = 2000000/period;
frequency2 = 2000000/period2;
}

void output(){
printf("Frequency = %ld Hz, Period = %d.%d microseconds. ", frequency,period/2,(period%2)*5);
printf("Frequency2 = %ld Hz, Period2 = %d.%d microseconds\r", frequency2,(period2)/2, (period2%2)*5);
}

void main(){
initialization();
while(1){
calculate();
output();}
}