Overview: 8 Device Drivers

GEOS does as much as possible to isolate applications from the hardware in use. Not only does this allow applications to run with thousands of different system configurations, but it also allows them to work properly with any new technology not yet developed--when a new device is introduced and a driver written for it, applications will automatically work with it (in most cases).

Device drivers are used by the kernel for all of the following:

Video Cards
Most video cards with graphics are supported including HGC, CGA, EGA, VGA, and Super VGA.
Keyboards
International keyboards are supported for most languages using available character sets.
Pen Input Devices
New input devices such as digitizers, touch screens, and other types of devices are or can be easily supported by drivers that translate the input into standard mouse-and-keyboard style input.
Printers
Standard 9-pin and 24-pin dot matrix printers as well as most laser printers are supported. PostScript output is also supported.
Mice
Dozens of different mice are supported.
Serial and Parallel Ports
Serial and parallel ports are driven by special types of Stream Drivers and can be used to create fax and other peripheral drivers.
File Systems
File systems (MS-DOS and DR DOS, for example) are supported through file system drivers. Future releases of file systems and alternatives will be supported through the addition of new file system drivers.
Task Switchers
GEOS interacts with DOS task-switchers through task switch drivers.
Power Management Hardware
Many portable computers (notebooks and palmtops) use power management hardware to extend the life of their batteries. GEOS works with the power management systems through a power management system driver.
Font Rasterizers
GEOS uses a combination of outline and bitmap fonts. Different font engines are supported through font rasterizers.

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7 Libraries