Black Box High Speed COS-4, Руководство пользователя

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HIGH SPEED COS-4 AND HIGH SPEED COS-8
If unwanted switching continues to occur, try lengthening the graphics-
mode pause. (This is the period of time that must elapse
after
the COS 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’s
DIP switch SW1 differently (see
Section 3.2
).
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’s Mode
switch to the TR (Transparent, right-hand) position. While the COS is in
Transparent mode, the arming code is ignored, and the MODE LED is lit
to remind you that switching is impossible until you change modes.
5.3 The Barber-Pole Self-Test
To have the High Speed COS-4 or COS-8 perform a self-test of its
transmission circuitry, unplug it, open it up as described in
Section 3.2
, and
set position 6 of its DIP switch SW1 to ON (up). Connect Port 1 to a
terminal or other RS-232 device whose data rate and data format match
those selected on the COS. Close the COS and turn it back on: The COS
will begin outputting the following items to the RS-232 device connected to
Port 1
only
:
• The COS’s EPROM version; then
• The current settings of switches SW1 and SW2; then
• A continuous “barber pole” pattern of ASCII characters.
To end the test and return to normal operation, take these steps:
1. Turn the COS off again;
2. If necessary, disconnect the RS-232 device from Port 1 and reconnect
the original equipment;
3. Reopen the COS;
4. Set position 6 of the COS’s DIP switch SW1 to OFF (down);
5. Reclose the COS (and make sure to screw the case back on securely);
and
6. Turn the COS back on again.