FUNCTIONAL DESCRIPTION.

TB 11-5820-890-12

Figure 1-2. ANCD Rear View

1-13. FUNCTIONAL DESCRIPTION.

The ANCD is a hand held key management and communications device that is made user friendly by the

extensive use of menus. Interaction between the ANCD and the operator is via the 35 key keyboard and the 2-

by-24 character window in the LCD display. This is possible because of the onboard Basic Input/Output System

(BIOS)/DOS service routines. The BIOS provides the lowest level interface between the ANCD and the

application software. The BIOS is made up of standard services as defined for the PC-XT and a set of unique

services for the ANCD. The standard services support the display, keyboard, disk drives, serial and parallel

ports, time of day, and other features needed by higher level software. The non-standard service provided in the

BIOS allows higher level software to access the hardware differences between the PC-XT and ANCD. This

service supports the DS-10C and DS-102 interface, variable clock rate, power conservation, display illumination,

keyboard keys to be programmable, security, and other features unique to the ANCD that are always part of the

operating environment.

Block diagrams for the ANCD subsystems can be seen at Figure 1-3.

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