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- text/9/5
- The computer has several timing
- crystals which keep its thinking
- organized. One is also used to keep
- track of the time and date. Many
- computers also have a small
- rechargeable battery and an IC chip
- that keeps track of the time even
- when the main power switch is
- turned off. This small part of the
- computer is always awake.
-
-
- ~
- text/9/96
- The timing crystal puts out an
- electronic tick, tick, tick at a
- very high rate of speed. The timing
- chip adds these ticks to the time
- and date. The battery keeps this
- going. Whenever the computer is
- turned on, the battery is recharged.
-
-
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- text/345/6
- The computer loads a program
- from a disk into the RAM. Hard
- disk usually spin at 3600
- revolutions per minute and
- floppies run at 300 RPM. The
- hard disk can hold more
- information than a floppy, but
- their principal of operation is
- the same.
-
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- text/345/88
- The surfaces of a disk are
- coated or plated with a magnetic
- metal. A small recording head
- is placed very near each
- surface. The head can be moved
- in and out along the radius of
- the disk, so that it can read or
- write along any of many tracks,
- called cylinders.
-
- ~