Video Board; Serial Channel Interface; Plato Communication Interface; Device Inputs And Outputs - Control Data Corporation INFORMATION SYSTEMS TERMINAL II Hardware Maintenance Manual

TABLE 1-1. DEVICE INPUTS AND OUTPUTS
DEVICE
MICROPROCESSOR
INPUT/OUTPUT
Memory
Both
Keyboard Input
PLATO communication interface
Both
Serial channel Both
Maintenance LEOs
Output
Switches
Input
ID code setting
Input
Touchpane1 Input
Parallel channel
Both
Interrupt mask
Output
VIDEO BOARD
The video board provides timing and memory to support the
controller board and the display module. Features are:
a. 32K 8-bit words of RAM for crt refresh
b. 16K 8-bit words of RAM for programs (basic memory)
c. Provision for 16K 8-bit words of RAM expansion
d. 2K 8-bit words of ROM/EROM for terminal diagnostic
and loader program
e. Timing generation for the display, memory, and con-
troller board
f. Composite video output for external devices
The video board has in it the supporting logic for the
memory expansion, including sockets where the memory chips
are inserted. This feature expands the basic 48K-word RAM
to 64K words (8-bit words). This increases the capacity of
the random-access memory dedicated for programs from 16K to
32K 8-bit words. This memory expansion feature consists of
the addition of eight memory chips.
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