||Synchronous data at 50, 56, 64, or 76.8 kbps.
||Full duplex operation. Four control signals (RTS, CTS, DSR and DCD) are multiplexed along with the data and clock signals.
||Signal levels and format conform to the requirements of CCITT recommendation V.35. Two digital connectors are provided on each card. If the female connector is used the port will appear as a modem; if the male connector is used the port will appear as a terminal.
||Operating temperature is 0 degrees C to +50 degrees C, up to 95% relative humidity (non-condensing), up to 10,000 feet altitude.
The MP918 operates as a buffer between the external interface and the CAM-1 (channel allocation master) card in Versimux. It combines the interface and test control signals into a master control signal. It then passes this signal, along with the transmit data and clock signals, to the CAM-1 card. The CAM-1 card combines the three signals from each of the port cards into a master aggregate signal. The master signal is used to turn the light source on and off, generating a series of light pulses which are sent over the fiber optic cable. At the remote end the process is reversed. The three main signals are recovered from the CAM-1 card and supplied to the appropriate port card. The master control signal is then demultiplexed and applied to the interface along with the data and clock signals.
The MP918 port may be operated as a modem link or as an interface extender, as shown in the diagrams below. When the MP918 is used as a modem link both ends of the link appear as modems. When it is used as an interface extender, the link appears as a modem to the terminal and as a terminal to the modem.
In either configurations, the MP918 will supply both transmit and receive clocks or operate with an ext ernal transmit clock, as required.
The status indicators on the MP918 are color coded to simplify operation. A green lamp provides positive indication of normal operation. Red lamps are used to indicate an alarm condition or an interruption in data traffic. Red lamps should be off for normal operation. Yellow lamps are used to indicate that the associated interface signals are present at the connector.
The following paragraphs describe the different indicator lamps used on the MP918.
|PWR 918 (green)
||An on condition indicates that both positive and negative
operating voltages are present.
|OUT SYN (red)
||An on condition indicates that the local receiver has lost synchronization.
|RTS, CTS, DSR,
DCD, TD, RD
|These lamps will be on when the associated interface signals are
present at the connector.
|TEST ERR, TEST,
REM IN TEST (red)
|These lamps are used to indicate the status of a diagnostic test.
The MP918 port card is installed in the Model OMC-14 Versimux chassis. This chassis holds a total of 14 multiplexer pport cards and mounts into a standard 19" rack. Data port cards and telephone port cards may be combined in the same chassis. Power supplies and channel allocation master cards are also required in each Versimux chassis.