| Knox Video RS4x4HB OPERATION SECTION
Operation Section || Maintenance Section || Serial Protocols
INTRODUCTION
This section explains in detail the operation of the RS4x4HB using either the
front panel push-button switches or the RS232 port.
CONNECTIONS
When installing balanced audio
connections, use the center pin for the common or ground wire. The top
or bottom pin may be used for either + or - , however the connections must
be consistent throughout.

Connect audio and video sources as described in sections 2.4 and 2.5. There is
no requirement that all inputs be used.
If outputs are left over they may be used like a distribution amplifier to
buffer and distribute an input signal. To use extra outputs in this way simply route the
input you wish to distribute to as many available outputs as desired.
Outputs may be looped back to unused inputs via short cables for
the purpose of adding delays, but be aware that if an output is then routed to that same
input an illegal condition will exist and the output will oscillate at frequencies which
could spill over onto other crosspoints.
ROUTING VIA THE FRONT PANEL SWITCHES
HOW TO ROUTE AUDIO AND VIDEO TOGETHER
Select the destination (output) you wish to route a signal to and push (and
release) the front panel button with the number; the row of LEDs to the right of the
button you pushed will flash. Then select the source (input) audio and video you wish to
have routed to that output and push the front panel button with that input number. The row
of LEDs will stop flashing and the lamp corresponding to that crosspoint will then glow
steadily.
If you do not push an input button within ten seconds, the LEDs will stop
flashing and the crosspoint will remain where it was.
HOW TO ROUTE AUDIO SEPARATELY
Select the destination (output) you wish to route an audio signal only to and
push the front panel button with that number twice (two quick pushes). The row of LEDs to
the right of the button you pushed will flash, as when you route both signals together.
Then select the source (input) audio you wish to have routed to that output and push the
front panel button with that input number. The row of LEDs will stop flashing and the lamp
corresponding to the audio crosspoint will flash slowly, while the LED corresponding to
the video crosspoint will glow steadily. If you do not push an input button within ten
seconds, the LEDs will stop flashing and the crosspoint will remain where it was.
HOW TO STORE AND RECALL CROSSPOINT PATTERNS
The RS4x4HB has 4 stored routing map configuration memory locations. These
stored configurations are non-volatile and are thus maintained during power
interrup-tions.
To RECALL and load one of the four stored crosspoint patterns from the front
panel, push and hold input button #1; an R will appear on the LED display. Then release
button #1 and push an output button, 1 to 4, corresponding to the crosspoint pattern you
wish to recall.
To STORE the currenetly loaded crosspoint pattern to one of the four pattern
storage areas, push and hold input button #4; an S will appear on the LED display. Then
release button #4 and push an output button, 1 to 4, corresponding to the storage area you
wish to store the crosspoint pattern in.
HOW TO START THE TIMED SEQUENCER
The RS4x4HB can be set to cycle continuously through its four stored patterns on
a timed basis. To start the cycling, push and hold input button #2. Push and hold input
button #2 again to stop the cycling. The Timed Sequencer can be disabled by putting switch
4 in the ON position.
SERIAL PROTOCOLS
Operation Section || Maintenance Section || Serial Protocols
ROUTING VIA THE RS232 INPUT
A simple protocol allows all crosspoints to be set through the RS232 port.
The RS232 port will accept inputs from a terminal, computer, or other software-driven
control device. No handshaking is required, but the RS4x4HB will answerback in one of two
modes to each command received (see section 3.5 for details).
The RS4x4HB RS232 Port is configured as a DCE. The pin-out of this Port allows
connection to an IBM-PC or compatible 9 pin serial COM Port with a 1:1 cable.
Pin connections for the DB9 are as follows:
Data is sent from the router on pin 2.
Data is received by the router on pin 3.
Pin 5 is ground.
SETTING THE BAUD
RATE
The router is shipped with the baud rate set at 9600.
The baud rate may be reset using positions 1 and 2 of the dip switches
located on the rear panel of the router. Set the switches for the
desired baud rate as follows:
| Baud
Rate |
SWITCH
1 |
SWITCH
2 |
| 19200 |
ON |
ON |
| 1200 |
OFF |
OFF |
| 2400 |
ON |
OFF |
| 9600 |
OFF |
OFF |
*All baud rates are 8 bit, no parity, one
stop bit.
Switches are ON when pushed to the right (as viewed from
the back of the panel) The switches are read by the microprocessor
only at power up; for switch configurations to take effect, cycle the
power input to the router.
ROUTING AUDIO AND VIDEO
To route video only, send a four-byte command in the form:
Vxy (ENTER),
Where x is an output number and y is an input number.
To route audio only, send a four-byte command in the form:
Axy (ENTER),
Where x is an output number and y is an input number.
To route both audio and video, send a four-byte command in the form:
Bxy (ENTER),
Where x is an output number and y is an input number.
To route both audio and video from different inputs, send a five-byte command in
the form:
Bxyz (ENTER),
Where x is an output number, the first y is a video input number, and z is an
audio input number.
A crosspoint can be turned off by routing it to input zero; e.g., B10 (ENTER)
turns output number 1 OFF.
Each time a routing command is sent, the RS232 output line responds in
accordance with the verbose/non-verbose switch setting (see section 2.7).
SENDING A SALVO COMMAND DESCRIPTION
It is possible to send the same input to a number of sequential outputs by a
single 5-byte command of the form:
Lmno [ENTER]
Where L means X for both audio and video, Y for video only, or Z for
audio only, m is the first output number, n is the last output number, and o
is the input number.
For example, X144[ENTER] sends the audio and video from input 4 to outputs 1
through 4.
SENDING A STRING OF COMMANDS TO BE EXECUTED AT THE SAME
TIME
It is possible to send a set of commands to the routing switcher that will be
held until the final command is received, then all the commands are executed at the same
time. For all but the final command in the set use the form:
Lmno[ENTER]
Where L means E for both audio and video, F for video only, or G
for audio only, m is the output number and n is the input number. The final
command must start with the letter B, V, or A instead of E, F, or G or send the
command EE to TAKE the string.
For example, the following commands sent over some period of time E11[ENTER],
E22[ENTER], E33[ENTER], B44[ENTER] will result in connecting input 1 to output 1,2 to 2, 3
to 3, and 4 to 4 when the last [ENTER] is received.
STORING AND RECALLING CROSSPOINT PATTERNS
To RECALL and load one of the four crosspoint patterns in the battery backup
memory, send the three-byte command:
Rn (ENTER),
Where n is a number from 1 to 4.
To STORE the currently loaded crosspoint pattern to one of the four pattern
storage areas, send the three-byte command:
Sn (ENTER),
Where n is a number from 1 to 4. The pattern stored in that memory area will be
overwritten with the current pattern.
TIMED SEQUENCER
The RS4x4HB can be set to cycle continuously through its four stored patterns on
a time basis. To set the time interval and start the cycling send the four-byte command:
Tnnn (ENTER),
Where nnn is a one- to three-digit number from 1 to 999.
To stop the cycling, send the two-byte command:
N (ENTER).
ANSWERBACK MODES
The user may choose between two modes of answerback: verbose and non-verbose.
Select the mode using position 3 of the programming switch located on the rear panel of
the RS4x4HB. Position 3 ON is verbose. Position 3 OFF is non-verbose.
In the verbose mode, each time a routing command is sent, the current routing
map will be reported on the RS232 line followed by the word DONE.
The switches are read by the microprocessor only at power-up; for switch
configuration changes to take effect, cycle the power input to the RS4x4HB.
OUTPUT 1 VIDEO 3 AUDIO 1
OUTPUT 2 VIDEO 2 AUDIO 2
OUTPUT 3 VIDEO 1 AUDIO 3
OUTPUT 4 VIDEO 2 AUDIO 4
Figure 3.1 Typical Routing Map Status Report
In the non-verbose mode only the word DONE will be reported.
In either mode, an incorrect or meaningless command will cause the word
ERROR to be reported.
READING SYSTEM STATUS
The crosspoint status can be read from the RS232 port at any time by sending
the two-byte command:
D (ENTER)
The status report does not disturb the existing crosspoint pattern.
LAMP TEST
The lamp test which occurs automatically on power-up can be initiated through
the RS232 port by sending the two-byte command:
T (ENTER)
The lamp test does not disturb the existing crosspoint pattern.
MAINTENANCE SECTION
Operation Section || Maintenance Section || Serial Protocols
NOTE: Maintenance of the battery, should be performed by qualified service
people only.
INTRODUCTION
The only routine maintenance the RS4x4HB requires is to change the battery
located at the rear of the RS4x4 unit.
HOW TO CHANGE THE MEMORY BACKUP BATTERY
The RS4x4HB is shipped with a memory backup battery which retains the routing
crosspoint information when power is off. The battery, approximately ½ inch in diameter,
is mounted in a holder on the main printed circuit board. In the event that crosspoint
information is not retained during power off, the battery must be replaced.
To change the battery pry up the retaining bar gently and slip the old battery
out. Replace at least every five years with Knox part number 140896, or commercial type
DL1220.
Figure 4.2 Baud Rate Setting
Switch positions 5 through 8 are reserved for programming options not covered
here. Switches 5 through 8 should always be OFF.
SETTING THE BAUD RATE
An 8-position switch, accessible through the rear panel, is provided for setting
the baud rate and certain programming functions.
Switch positions 1 and 2 are used to set the baud rate for the RS232 control
port. One of four baud rates may be selected as follows:
| BAUD RATE |
SWITCH 1 |
SWITCH 2 |
| 19200 |
ON |
ON |
| 1200 |
OFF |
ON |
| 2400 |
ON |
OFF |
| 9600 |
OFF |
OFF |
SETTING THE ANSWERBACK MODE
The user may choose between two modes of answerback: verbose, and non-verbose.
Select the mode using position 3 of the programming switch located on the rear panel of
the RS4x43HB. Position 3 ON is verbose, position 3 OFF is non-verbose.
In the verbose mode, each time a routing command is sent, the current routing
map will be reported on the RS232 line followed by the word DONE.
The switches are read by the microprocessor only at power-up; for switch
configuration changes to take effect, cycle the power input to the RS4x4HB.
OUTPUT 1 VIDEO 3 AUDIO 1
OUTPUT 2 VIDEO 2 AUDIO 2
OUTPUT 3 VIDEO 1 AUDIO 3
OUTPUT 4 VIDEO 2 AUDIO 4
Figure 4.1 Typical Routing Map Status Report
In the non-verbose mode only the word DONE will be reported.
In either mode, an incorrect or meaningless command will cause the word ERROR to
be reported.
Switches are ON when pushed up.
DISABLING THE TIMED SEQUENCER
The Timed Sequencer can be activated accidentally from the front panel
pushbuttons. To avoid this condition, disable the Timed Sequencer by putting switch 4 in
the ON position.
Operation Section || Maintenance Section || Serial Protocols |