PIC MICROCONTROLLER
ARCHITECTURE OF 8085
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Used when it is necessary to measure longer periods of time
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Used to make a short periods of time
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Used to create counter
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No answer
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Detailed explanation-1: -A prescaler divides down the clock signals used for the timer, giving reduced overflow rates. The rate can be set to a number of possible values. The exact values are chip-dependent; e.g., for the PIC16F877A values area a number of values are available ranging from 1:1 to 1:256.
Detailed explanation-2: -The purpose of the prescaler is to allow the timer to be clocked at the rate a user desires. For shorter (8 and 16-bit) timers, there will often be a tradeoff between resolution (high resolution requires a high clock rate) and range (high clock rates cause the timer to overflow more quickly).
Detailed explanation-3: -In our case this means that we should select prescaler starting from 1:16 because the maximum period for a 1:16 prescaler is 65.5 ms which can accommodate a 50 ms pulse. You could also select from 1:32 to 1:256 prescalers to measure the pulse.
Detailed explanation-4: -The timer is nothing but a simple binary counter that can be configured to count clock pulses(Internal/External). Once it reaches the max value, it will roll back to zero setting up an Overflow flag and generates the interrupt if enabled.
Detailed explanation-5: -The prescaler is off by 1 because it’s 0-based: a PSC value of “0” means to use a prescaler (clock divider) of 1. Set the Counter Period to 65535.