6.5.3+Interrupts+and+Polling

=__**Define interrupt and Polling**__=


 * __Interrupts__**

Interrupts are very simple
 * A CPU core can only work with one process at a time, therefore in order to handle multiple tasks the current tasks are stopped in order to process a more important task
 * When the interrupt signal is sent then the CPU pauses its current process and starts handles the interrupt
 * When the task resulting from the interrupt is completed, the CPU resumes with the tasks it was doing before it received the interrupt
 * //See hardware and software interrupts on page 6.1.3 Interrupt Register//


 * __Polling__**
 * Polling is the process where the computer waits for an external device to check for it readiness.
 * The computer does not do anything else than check the status of the device
 * Polling is often used with low-level hardware
 * Example: when a printer connected via a Parrnell port the computer waits until the next character has been received by the printer.
 * These process can be as minute as only reading 1 Byte.

Created By: Daniel Gillo, Edited by Jocbe Last update: 7th January 2011

Sources:
 * "Polling (computer Science)." __Wikipedia, The Free Encyclopedia__. 4 September 2010. Wikimedia Foundation. 7 January 2011. __http://en.wikipedia.org/wiki/Polling_%28computer_science%29__
 * Jones, Richard. __Computer Science Java Enabled__. Victoria: IBID Press, 2004.