(CCS) printf bug?

#include <16F877a.h>
//#include <18f452.h>
#device adc=8
#use delay(clock=4000000)
#fuses NOWDT,XT, PUT, NOLVP
#use rs232(baud=9600,xmit=PIN_C6,rcv=PIN_C7)
#use i2c(Master,Fast,sda=PIN_C4,scl=PIN_C3)

void main() {
int8 z=0;

while(1) {
z++;
printf("press any key to start\n\r");
getc();

printf("i love it!");
printf("%2u\n\r", z);
}
}

The screen stop responding if i pressed and held down the key (any key) for a while. However, if i commented out the
//printf("press any key to start\n\r");
the system works fine.

#include <16F877a.h>
//#include <18f452.h>
#device adc=8
#use delay(clock=4000000)
#fuses NOWDT,XT, PUT, NOLVP
#use rs232(baud=9600,xmit=PIN_C6,rcv=PIN_C7)
#use i2c(Master,Fast,sda=PIN_C4,scl=PIN_C3)

void main() {
int8 z=0;

while(1) {
z++;
//printf("press any key to start\n\r");
getc();

printf("i love it!");
printf("%2u\n\r", z);
}
}


Could anyone tell me why does it happen?