Ericsson LBI-39224 manual Frame Format, Line Code, Signaling Type

LBI-39224

one full duplex 4-wire 600-ohm audio channel provided by the Audio Board. The T1/E1 Interface Card extracts a signal from one bus slot and sends it out on a T1/E1 channel. Accordingly, signals received on this same T1/E1 channel are applied to a different CEC/IMC TDM bus slot.

–Digital voice/data using subrate ports mode (currently not supported)

–Digital voice/data using T1/E1 mode (currently not supported)

Line Type

This is a read-only field which indicates which type of line (T1 or E1) that the system is configured for.

Frame Format

Framing deals with how the digitized data stream is configured (formatted), a data stream with one framing format would not be recognized by a system with another frame format. The possible T1 formats are 4-Frame Multiframe (F4), 12-Frame Multiframe (F12, D3/4), Extended Superframe (ESF), and Remote Switch Mode (F72). The possible E1 formats are Doubleframe and CRC Multiframe. The format is determined by the service line used. Select from the available choices in the drop-down list box to match the line format.

Line Code

The line code indicates the method used to encode long strings of zeroes. The receiving end of a T1/E1 link would not be able to remain in sync if long strings of zeroes were transmitted. The possible T1 line codes are B8ZS and AMI w/ZCS. The E1 line code is HDB3. The line code also is determined by the service line utilized. Select from the available choices in the drop-down list box to match the line.

Signaling Type

This signaling is used by the T1/E1 Interface Card to transmit channel status information (busy or idle). T1 uses bits robbed from the channel data to convey this information. E1 uses a dedicated channel to send signaling information for all channels; therefore, only 30 user channels are allowed. In a CEC/IMC system, signaling must be set for MIM site interfaces, and the T1/E1 muxes and base stations at the associated site location must be configured for E&M Signaling unless the site is all digital (no analog voice). Signaling should not be set for any other device types. The types of signaling are No Signaling (both T1 and

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