TM 5-6675-316-14
(4) Keyboard counter/load register. The keyboard counter just counts key-
strokes. These are transferred into the keyboard load register when the register
receives an accept command from the program. This data is then passed via the 1/0
gates to the data bus. The program then goes to the keyboard buffer in the display
memory, pulls out the character code stored there and displays it on the CRT screen.
The program only selects those codes contained in the keyboard load register which
acts as a buffer. There are two buffers; while the program takes character codes
out of one, the operator can continue typing and loading information into the other.
m . D/A stepper board J11.
The board is divided into the following functions:
Program Interface
Flash Intensity Control
Clock Interface
Row Shift Stepping Control
(1) Program interface. Acts as a four-register storage with associated
buffers. Received information is buffered and then placed on the data bus.
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