10
Channel switching by external control
The OPTIONS port featured on every AV4PRO-VGA allows external control of
the current channel either by the optional RC4 controller, commands sent via
RS-232 serial input or by switching one of the four channel select input lines. For
more details about the necessary RS-232 serial cable, see
Appendix 2
.
OPTIONS port pinout
The OPTIONS port can accept either 8p8c or 10p10c connectors, as required.
To connect a computer or device for remote control
1 Insert the 8p8c or 10p10c connector of the cable to the
OPTIONS
port on the
rear panel of the unit.
Control by RS-232 serial
Where the external control is via RS-232 signal, ensure that the configuration
menu option is set to or to enable RS-232 control.
Serial port parameter settings
Ensure that the chosen serial port is configured to the following:
• Baud rate: To match setting of
option in the
Configuration menu
• Data bits:
8
• Stop bit:
1
• Parity:
None
Serial port channel selection codes
ASCII
Character Hex Decimal
• Channel 1:
‘1’
0x31
49
• Channel 2:
‘2’
0x32
50
• Channel 3:
‘3’
0x33
51
• Channel 4:
‘4’
0x34
52
Note: As each channel is chosen using the above RS-232 commands, the
peripherals that will be transferred are determined by the current setting of the
switching mode.
Control by channel select input lines
Where the external control is via the four channel select input lines of the
OPTIONS port (see pin out opposite), ensure that the configuration menu option
is set to to enable the input lines.
The four input lines are suitable for connection to dry contacts or open collector
style outputs. Connecting an input line to GND will cause the AV4PRO-VGA to
switch all of its functions to the selected channel:
• Channel 1:
Channel select input
1
low
• Channel 2:
Channel select input
2
low
• Channel 3:
Channel select input
3
low
• Channel 4:
Channel select input
4
low
If the input line is held low then all other switching requests by other means will
be ignored until the line returns to a high (open) state.
If more than one logic input is low (closed) then the lower channel number takes
priority.
Note: The input lines have only limited protection against over voltage.
8p8c
10p10c
Signal
1
Channel select input 1
1
2
5VDC power output (100mA max)
2
3
GND reference for all signals
3
4
RS232 (RXD) data receive
4
5
RS232 auxiliary data transmit (reserved)
5
6
RS232 auxiliary data receive (reserved)
6
7
RS232 (TXD) data transmit
7
8
Channel select input 2
8
9
Channel select input 3
10
Channel select input 4
1
10
OPTIONS
2 Connect the other end of the cable to a vacant serial port on the computer
or to the output of the switching device.
4
USER
CO
NSOLE
OPTIONS
