XRT79L71
PRELIMINARY
431
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
REV. P2.0.0
For information on how the Transmit DS3/E3 Framer and Receive DS3/E3 Framer blocks handle the MA byte,
The Pre-October 1998 Version of the MA Byte
The Pre-October 1998 Version of the MA byte contained the following bit-format.
Bits 6 and 7 - Payload Dependent
Bit 8 - Timing Marker
The Network Operator Byte (NR)
This byte is allocated for maintenance purposes specific to individual network operators. The XRT79L71
permits the user to transport either a proprietary message or a LAPD/PMDL Message via the NR byte.
Information on how to transmit and receive a proprietary message via the NR byte can be found in SEE”USER respectively. Information on how to transmit and receive a LAPD/PMDL Message via the NR byte can be
The General Purpose Communications Channel Byte (GC)
This byte is allocated to provide either a data or voice channel for maintenance purposes. The XRT79L71
permits the user to transport either a proprietary message or a LAPD/PMDL Message via the GC byte.
Information on how to transmit and receive a proprietary message via the GC byte can be found in SEE”USER respectively. Information on how to transmit and receive a LAPD/PMDL Message via the GC byte can be
6.2
THE TRANSMIT DIRECTION - E3, ITU-T G.832 CLEAR-CHANNEL FRAMER APPLICATIONS
Now that the basics of the E3, ITU-T G.832 frame structure have been discussed; the next several sections
present an in-depth functional description of all of the blocks that are operating in the Transmit Direction, within
the XRT79L71, when configured to operate in the "Clear-Channel E3 Framer" Mode. Figure 204 presents a
functional block diagram of the Transmit Direction circuitry within the XRT79L71.
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 8
FERF/RDI
FEBE/REI
Payload_Type[2:0]
Payload Dependent[1:0]
Timing
Marker