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capable of dividing the screen into upper and lower areas called the
"workspace" and the "monitor", respectively.
Text from the keyboard or
computer can be directed to either area. Local memory allows the 4025
to store up to ten pages (screens) of text which can then be "scrolled"
on or off the screen using keyboard commands. Other options and features
of the 4025 are discussed in the 4025 User's Manual and the 4025 Programmer's Guide.
Sec. 3.7
11/04 - CAMAC Interface
The circuit boards which make up the 11/04 system are interconnected
by a common backplane called the Unibus. The Unibus consists of 56 signal
lines which carry data and commands to each board within the computer.
For making connections to external devices, the computer backplane is
brought outside the cabinet via an Unibus extension cable. A 14,2 m Unibus
extension cable has been installed between the computer and the CAMAC
crate. Tests were made to ensure that the capacitive loading of the cable
did not degrade the rise and fall times of the signals on the bus. The
results are shown in the oscillographs of Figs. 3-8 and 3-9. Shot 3-8(a)
depicts the signals on an address line without the extension cable. Shot
3-8(b) shows the effect of the unterminated extension cable. Shot 3-9(a)
and (b) show the response on the bus with the Unibus terminator board
properly installed in the connector block at the CAMAC crate. The rise
and fall times to H L levels (0.8 V - 2.0 V) are about 20 ns and are
almost identical to the response of the unextended backplane.
To protect the system from electromagnetic interference (EMI) the
Unibus extension cable and the remote terminal lines are enclosed in a