You have to write a loop that will wait for a bit in PORTB to be cleared. It is on pin 5 (just like the push button on your VIVA board when the shorting block is set correctly) and is usually held high by a pull-up resistor to Vcc until a button is pushed that shorts the pin to ground. When this pin goes low, you should then drop through to label Phase2 to continue the application with some unknown other code. I suggest you use one of the bit test instructions. Dont forget the BANKSEL where needed.

In assembly