Appendix B: Control panel protocol
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Appendix B: Control panel protocol
The SDC 8200 conference and interpretation system supports a control
panel. The central unit sends a control command to the connected control
panel:
y
when a delegate or chairman unit is activated,
y
when a delegate or chairman unit is deactivated,
y
when a microphone goes into request mode,
y
when all active microphones are deactived simultaneously
(priority function).
The control panel sends a control command to the central unit:
y
when a delegate or chairman unit is to be activated,
y
when a delegate or chairman unit is to be deactivated,
y
when the control panel is to be reset (Reset).
The control panel must be connected to the central unit’s COM 2 interface
(RS 232 connection). The settings for the communications port for the
control panel are:
Bits per second: 19,200
Data bits:
8
Parity:
None
Stop bits:
1
Flow control:
None
Commands
All commands sent by the central unit start with a “%” sign. The last
character is a character which states the end of the transmission. Just
before the end-of-transmission character, there are four characters within
the command sent to the camera control which account for the CRC
checksum.
The CRC checksum is in uppercase hexadecimal form while all other
numbers are in decimal form.
STX “%”
data
CRC
ETX
Start of
Transmission
Character
(0x25 = “%”)
Data of the
command
16 bit sum of the
ASCII characters
between STX and
CRC
End of
Transmission
Character
(0x0D)
