Black Box SW056A, Quick Start Manual

Page: 6 / 18

CHAPTER 3: Installation
5
3.1 Setting the DIP Switch Banks
Turn the COS-16 upside-down. Two banks of DIP
switches lie in the center of the case, towards the
face of the unit. SW1 lies closer to the middle of
the unit, and SW2 lies closer to the face of the unit.
Both banks govern portions of your switching code,
the two-character ASCII code that sets the switch to
the proper port. The code consists of the following:
• a prefix character, which signals the switch
to an upcoming action
• and a port character, which directs the Switch
to the proper port.
Three of the four switch charts you’ll use to set the
banks are posted to the left of the recess, and are
also reprinted in the Quick Setup Guide. A fourth,
larger chart is printed in Appendix A.
The 0, or off position for all DIP switches is the left
position. The 1, or on position for all DIP switches
is the right position.
3.1.1 F
UNCTIONS OF
B
ANK
1
Prefix Code Repetition (Switches 1 through 4)
If your prefix code shows up in the data stream,
the switch will react as if it had received a switching
instruction. To prevent false switches, you should
make the prefix code a character that does not
occur in your files.
A more effective measure is to require that the
switch receive two, four, or eight repetitions of the
prefix code before it actually switches. The Prefix
Code Repetition feature gives you this option. The
chart below (also on the bottom of the case) gives
the arrangement of the first four DIP switches.
Prefix Codes Switch # and Position
Required 1 2 3 4
1 1 0 0 0
2 0 1 0 0
4 0 0 1 0
8 0 0 0 1
Broadcast (Switch 5)
Broadcast mode distributes the data from the
common port to all ports. It is useful for simulta-
neous transmission or control of all input devices.
You can set it with the DIP switches, or set it using
an ASCII sequence (see Section 4.3). The chart
below, and on the bottom of the case, gives
the setting.
Broadcast Switch 5
Mode Position
OFF 0
ON 1
Baud Rate Select (Switches 6 through 8)
The speeds the COS-16 runs at range from 150 bps
up to 19,200 bps. Use the final three switches of
Bank 1 to set the COS properly. The chart below,
also printed on the case, gives the arrangement.
Switch # and Position
Speed (bps) 6 7 8
150 1 1 1
300 0 1 1
600 1 0 1
1200 0 0 1
2400 1 1 0
4800 0 1 0
9600 1 0 0
19,200 0 0 0
3.1.2 F
UNCTIONS OF
B
ANK
2
Prefix Code (Switches 1 through 7)
You can use any ASCII character for your prefix
code, but bear in mind that it will be passed
through the output port to the connected device.
If you choose a printable character, and use the
COS-16 with printers or other output devices,
the prefix will print at the beginning of your file.
For this reason, a control character or other non-
printable ASCII code is a wiser choice. You should
also choose a character that should never show up
in your data files, to eliminate the possibility of a
false switch. If you are working with binary files,
such as graphics or communications-package data,
3. Installation