The OCU-DP (Office Channel Unit – Data Port) is used to interface directly to Data Service Units (DSUs)/Channels Service Units (CSUs) supporting data traffic up to and including 64Kbps. A four-wire circuit can connect the OCU-DP card to a DSU/CSU that can be located up to four miles away. In switched 56 Kbps mode, users can access the network on an as-needed basis by dial-up commands. The system unit must be equipped to provide -48 VDC power to fully support the functionality of the OCU-DP card.

Each OCU-DP port can be independently programmed to operate at 2.4, 4.8, 9.6, 19.2, 56, SW-56 and 64 Kbps in either DS0-A, (one channel per DS0) or DS0-B format, which allows multiple data ports from multiple OCU-DP cards in the system to be mapped into the same DS0 time slot. If the DS0-B format is selected, the user then specifies the type of DS0-B format required (b-5, b-10 or b-20) and the subrate position that the data port occupied by the data port within the DS0-B frame.

In switched-56K mode, an OCU-DP port provides a connection for an external switched-56K DSU/CSU that will perform all call set-up and dialing functions. The OCU-DP card converts the call set-up commands into standard signaling and sends the signaling over the WAN facility.

All OCU-DP cards support a low speed secondary channel that is established in the 8th bit position of the DS0 time slot to which the OCU-DP port is assigned. The secondary channel can be used for testing and maintenance of the main circuit or for the transmission of other, independent, low speed data.

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Key Features
  • 5 port and 10 port versions available
  • Supports data circuits up to 64Kbps
  • Supports CSU/DSU up to four miles away
  • Supports switched 56Kbps circuits
  • Allows provisioning of DDS services
  • Allows consolidation of DSU traffic as DS0-A or DS0-B
  • 8″ x 7.5″, 20cm x 18.75cm
  • 5-port: 10 Watts, 30.65 BTU/hr
  • 10-port: 19.8 Watts, 62.17 BTU/hr
  • 5-port: 5 RJ-48 connectors
  • 10-port: 10 RJ-48 connectors
  • AT&T 62411, Bellcore TA-TSY-000077, TA-TSA-000083, Pub 62310, ANSI T1.107-1988
  • Operating temperature 0 to 50C, 32 to 122 F
  • Storage temperature -20 to 80 C, -4 to 176 F
  • Humidity 0 to 95% humidity, non-condensing
Geek Specs
  • Data format Synchronous-binary, serial
  • Data encoding Bipolar, return to 0, AMI
  • Line interface 4-Wire
  • Speeds 2.4, 4.8, 9.6, 19.2, 56 SW-56 and 64 Kbps
  • Sub-rate framing format DS0-A, DS0-B with 5, 10 or 20 divisions per DS0
  • Error correction Majority vote for speeds 9.6 Kbps or all less
  • Secondary channel As described in AT&T 62310, 62411 Addendum (pass through only) and TA TSY 000077 and TA TSY 000083, a separate lower speed data circuit which may be used for testing and maintenance. Modes are on or off.
    Secondary speeds supported are:
    Primary port rate / Secondary port rate
    56 Kbps / 2,666 bps
    19.2 Kbps / 1,066 bps
    9.6 Kbps / 533 bps
    4.8 Kbps / 266 bps
    2.4 Kbps / 133 bps
  • Operation modes OCU or CSU (software selectable per line)
  • Loopbacks Off, DTE, Net-a, Net-d (software selectable) (Net-a loops 4 wire interface to the network, Net-d loops the network at card interface to system bus).
  • Loopback generation (latching) Various loopbacks sent in-band to remote equipment: Off, DS0-n (loops the analog interface of the remote for 56K or less rate), CSU-N (loops the 4-wire interface of the remote), CSU-N (l00ps the 4-wire interface of local device).
  • Loopback detection Off, On, On with 10 minute time-out (latching and non-latching)

Ordering Information

IMACS 8000, OCU-DP, 5P
IMACS 8000, OCU-DP, 10P