Black Box COS-2, Manual

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CHAPTER 5: Operation
5.1 Power-Up
Turn on power to the High Speed COS-2 using the OFF/ON slide switch on
its front panel (see Figure 3-1 on page 11). If position 6 of the COS-2’s
right-hand DIP switch is set to OFF (down), the COS-2 will be ready to
operate normally. If position 6 is set to ON (up), the COS-2 will begin
performing its self-test (see
Section 5.3
).
5.2 Switching
At any time, you can switch between your two “slave” or “destination”
devices by sending the currently active arming code (see
Section 3.3
)
followed by the character correpsonding to the letter of the desired port
(either “B” or “C”).
The High Speed COS-2 has three switching modes: Text, Graphics, and
Transparent. While the COS-2’s front-panel “Mode” switch is in the Text
(left-hand) position, the COS-2 operates in Text mode: The arming code
and port character are recognized without a preceding pause. In Text
mode, both of the COS-2’s MODE LEDs are dark.
If you are using Text mode and you find that unwanted switching is
occurring, move the High Speed COS-2’s front-panel “Mode” switch to the
Graphics (center) position. In Graphics mode, a pause must occur before the
arming code is recognized, so incidental occurrences of the arming code and
the port character among data do not cause the COS-2 to switch as readily.
While the COS-2 is in Graphics mode, its left-hand MODE LED is lit.
If unwanted switching continues to occur, try lengthening the graphics-
mode pause. (This is the period of time that must elapse
after
the COS-2
stops receiving data in Graphics mode
before
it will recognize the arming
code if it receives it.) Lengthen the pause by setting positions 7 and 8 of the
COS-2’s right-hand DIP switch differently (see Table 3-1 on page 12).
If you need to temporarily disable switching for some reason (for
example, if you know there will be delays longer than 500 milliseconds
during the transmission of a graphics file), you can move the COS-2’s
Mode switch to the Transparent (right-hand) position. While the COS-2 is
in Transparent mode, the arming code is ignored and the right-hand
MODE LED is lit.
5. Operation