Polycom DOC2237A manual When the MCU is set as a DCE

MGC Hardware and Installation Manual

When the MCU is set as a DCE

The serial data stream flows from the endpoint (DTE) through the serial connector entering the MPI box by way of the 37-pin connector. The data is then directed from the 37-pin connector to the 160-pin connector connected to the MCU (DCE). In the MCU the data stream is converted to a TDM format, and then sent to the backplane information bus. Since this is a full duplex communication, the data is also bi-directional.

The network clock is enabled only when the span coming from the DCE to the MCU is active (i.e. handles a call). Therefore, the spans defined as Primary and Backup clock must be connected first when starting a conference and disconnected last when terminating the conference.

Figure 4-24, “MPI Data Flow when MCU is DCE” shows the data flow on a serial connection - the endpoints are connected directly to the MPI Box.

MCU (DCE)

MPI Box

	37- Pin
	Connector	Serial
	37- Pin	Connection
	Connector
160-Pin Cable		Serial
		Connection
	37-Pin
	Connector	Serial
		Connection
	37- Pin
	Connector
		Serial
		Connection

Figure 4-24: MPI Data Flow when MCU is DCE

Endpoint (DTE)

Endpoint (DTE)

Endpoint (DTE)

Endpoint (DTE)

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