An internal timing device. Using a quartz crystal, the CPU clock breathes life into the microprocessor by feeding it a constant flow of pulses. For example, a 200 MHz CPU receives 200 million pulses per second from the clock. A 2 GHz CPU gets two billion pulses per second. Similarly, in a communications device, a clock may be used to synchronize the data pulses between sender and receiver.
A "real time clock," also called the "system clock," keeps track of the time of day and makes this data available to the software. A "timesharing clock" interrupts the CPU at regular intervals and allows the operating system to divide its time between active users and/or applications. See per clock and clockless computing.
The CPU Clock
The quartz crystal generates continuous waves, which are converted into digital pulses.
A "real time clock," also called the "system clock," keeps track of the time of day and makes this data available to the software. A "timesharing clock" interrupts the CPU at regular intervals and allows the operating system to divide its time between active users and/or applications. See per clock and clockless computing.
The CPU Clock
The quartz crystal generates continuous waves, which are converted into digital pulses.
 | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2008 The Computer Language Company Inc. All rights reserved. |
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