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A p p e n d i c e s
CHS Translation
Cylinder, head and sector translation. Conversion of hard disk access addressing to the cylinder, head and sector form. The termi- nology is historical left from the days when data was stored on a series cylindrical drums. The head designates the reading device, similar to the head on your cassette recorder only mounted on a movable arm. Another addressing method is LBA.
CMOS RAM
Complementary metal oxide semiconductor random access memory. This is a technology for manufacturing random access memory which requires very low levels of power to operate.
COM Port
Abbreviation for communication port. This is your serial interface connection to other equipment.
Command
An instruction which you give your operating system. Example: run a particular application or format a floppy disk.
Configuration
The combination of hardware and software that makes up your system and how it is allocated for use.
CRT
Cathode Ray Tube.A display device which uses a beam of electronic particles striking a lumi- nescent screen. It produces a visual image by varying the position and intensity of the beam.
Data
The information a system stores and processes.
DC
Direct current.A voltage or current that does not fluctuate periodically with time.
Default Value
A preprogrammed value to be used if you fail to set your own.
DIMM
Disk
A spinning platter of magnetic data storage media. If the platter is very stiff it is a hard disk, if it is highly flexible it is a floppy disk,if it is a floppy disk in a hard housing with a shutter it is commonly called a diskette.
Disk Drive
The hardware which spins the disk and has the heads and control circuitry for reading and writing the data on the disk.
Diskette
A floppy disk in a hard housing with a shutter.
DMA
Direct Memory Access.Special circuitry for memory to memory transfers of data which do not require CPU action.
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