CPU – what is a clock interrupt?

I can't find the correct definition of this on the Internet

>Does every clock tick happen? > Does it happen every second? > Do you need to trigger some kind of alarm?

Solution

Clock or timer interrupt is the interrupt of the timer on the circuit board Configure these timers during board initialization, where you can define interrupt cycles

1. Does every clock tick happen?

The timer does not depend on the tick mark Both are the same After each interrupt or check, a variable named jiffies will be incremented This variable displays the number of ticks or interrupts the system booted

Does it happen every second?

The timer is configurable You can configure to generate interrupts after 1 second or 1 millisecond

3. Is it necessary to trigger some kind of alarm?

The alarm also uses a timer device But ticking or interrupting is different from an alarm clock Alarms are activated for some tasks, but the scale is recorded from Startup rather than manually modified

Please refer to any SOC data sheet, such as OMAP or STM, and read the timer section

For an introduction to timers, jiffies, and ticks in the Linux kernel, see the Linux device drivers [3E] page 07 time, delays, and deferred work