The X 86 Microprocessors: Architecture, Programming and Interfacing (8086 to Pentium) 2nd Edition by Pearson

PERIPHERAL INTERFACING–II 10-15

10.1.11 | Reading a Count

In many applications, it may be important to read the contents of the count-register.

This can be done by stopping the counting. To stop the counting, the method is to

make the GATE pin equal to 0 or to inhibit the clock. However, the better method is to

do the reading ‘on the fly’, which does not cause any interference on the circuit opera-

tion. Referring to Fig. 10.3 shows that there is a latch associated with the counting ele-

ment. To read a stable value from a counter, the method is to latch the count and then

read the content of the latch. Refer to Fig. 10.4 which shows the control ...