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Checking Bits


The code shown in the example loops until bit 3 of port T goes low. The code is checking bit 3 and as long as it is 1 the program loops. Other bits of port T will not have any affect on the looping. When checking a bit, put a 1 in the bit position of the bit you are trying to check. Put zeros in the bit positions not being checked.

How would the program be changed to wait for bit 3 to go high? ________________

A possible application of the above code could be waiting for an analog-to-digital (A/D) conversion to complete by checking a converter status bit. In a typical system, the conversion will be started (by setting/clearing a bit) followed by code that waits (by looping and examining a bit) for the conversion to complete.