HP HP-97 - II. Theory of Operation; HP-97 Logic

SECTION
II
Theory of Operation
2-1. HP-97 LOGIC
2-2. The main functional components e. PIK (printer interface control
of the HP-97 as shown in figure 2-1 and keyboard buffer).
are:
f. Printer assembly
a. Display
g. ROM's (read only memories).
b. Power supply
h. Anode buffers.
c. Keyboard.
i. Cathode driver.
d. ACT (arithmetic, control, and
timing). j. CRC (card reader chip).
k. Card Reader Assembly.
(RCD)
Cathode
Driver
DATA/ROM
6
(Low Battery)
DATA/ROM 5
KEYBOARD
Low Battery
E
R
ANOD
BUFFE
DISPLAY
DATA/ROM 2
ANODE
BUFFER
2
DATA/ROM 1
VTG VTs
Power
Supply
Printer
Card
Assembly
Reader
Assembly
VDD
LC Network
Figure 2-1. HP-97 Block Diagram