nonresident training course - Historic Naval Ships Association

Figure 3-5.—The tactical data path.
are used for CIGARS memory load commands. The
format of the external function word is shown in
figure 3-6.
Input Data Words
The input data words are formed by the display
console logic based upon operator actions. Most
operator switch closures or changes will result in the
generation of an input word. When the console
receives an interrogation EF, the console inputs the
input data word to the computer via the pulse
amplifier (PA) or direct computer interface (DCI).
Each data word sent to the computer consists of a
six-bit function code (lower six bits) with the
remainder of the word dedicated to data amplifying
the function as shown in figure 3-7. For instance, a
function code of 00 (binary coded octal) with all zeros
in the amplifying data indicates no new data since the
last interrogation (no operator switch actions since the
last interrogation). A function code of 01 indicates
the trackball is enabled. The amplifying data
indicates the coordinates of the trackball and range
selection of the console.
Input data words are developed for the console
display control panel and communication panel switch
closures, for the trackball and its control switches, and
for the digital data entry unit (DDEU) and computercontrolled
action entry panel (CCAEP) switches.
Output Data Word Types
The contents and functions of the computer words
generated by the CDS computer and outputted to the
Figure 3-6.—The external function (EF) word format.
3-6