Polycom SoundStructure C16 Hardware Installation Manual page 21

Because the OBAM interface is bi-directional, data will flow in both directions
on the single cable between devices. Due to this bi-directionality, do not loop
the OBAM link connections (as follows).
Once the devices are connected over OBAM, the SoundStructure devices will
behave as one large audio device, in other words, all the inputs from all the
SoundStructure devices are available on all the devices. Any combination of
SoundStructure C16, C12, C8, and SR12 devices may be linked together up to
a total of eight devices.
When the SoundStructure devices are connected over the OBAM Link, the
OBAM Input Status LED illuminates when there is a valid connection between
the OBAM IN port on this device and an OBAM OUT port on a second
SoundStructure device. This LED will not illuminate unless there is a valid
connection between the two devices. The OBAM Output Status LED
illuminates when there is a valid connection between the OBAM OUT port on
this device and an OBAM IN port on a different SoundStructure device. This
LED will not illuminate unless there is a valid connection between the two
devices.
A 12-inch OBAM cable is provided with each SoundStructure device. Should
longer OBAM cables be required, standard IEEE1394b "beta" cables may be
used. The maximum length of any single link between devices is 10 feet (3 m).
See OBAM Link for more details. An OBAM link cable may be tested by
inserting the same cable into the OBAM IN and OBAM OUT ports. If the
OBAM input and output status LEDs illuminate, the OBAM cable is fully
functional.
Device ID's
When multiple devices are connected via the OBAM interface, internal
SoundStructure device ID's are assigned automatically based on the OBAM
connections. The device that has no OBAM IN connection will be device 1. The
device connected to that unit will be device 2, and so on until the last device -
Installing The SoundStructure C16, C12, C8, And SR12
LAN C-LINK2 OBAM
IN OUT
LAN C-LINK2 OBAM
IN OUT
LAN C-LINK2 OBAM
IN OUT
PIN 2: TXD
PIN 3: RXD
PIN 5: GROUND
PIN 7: CTS
PIN 8: RTS
RS-232
IR
12V
PIN 2: TXD
PIN 3: RXD
PIN 5: GROUND
PIN 7: CTS
PIN 8: RTS
RS-232
IR
12V
PIN 2: TXD
PIN 3: RXD
PIN 5: GROUND
PIN 7: CTS
PIN 8: RTS
RS-232
IR
12V
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