DS3170 Maxim Integrated Products, DS3170 Datasheet - Page 96

• Manufacturer Part Number: DS3170
• Description: Network Controller & Processor ICs DS3-E3 Single-Chip T ransceiver T3-E3 Fra
• Manufacturer: Maxim Integrated Products

Table 10-30. Payload Label Match Status
XXX and YYY equal any value other than 000 or 001; XXX
The multiframe indicator and timing marker bits (sixth, seventh, and eighth bits of the MA byte) can be integrated
and stored in three register bits or extracted, integrated, and stored in four register bits. The bits (three or four) are
stored with a change indication. The multiframe indicator and timing marker storage type is programmable
(integrated or extracted). When the multiframe indicator and timing marker bits are integrated, the last three bits of
the MA byte are integrated and stored in three register bits. When the multiframe indicator and timing marker bits
are extracted, four timing source indicator bits are transferred in a four-frame multiframe, MSB first. The multiframe
indicator bits (sixth and seventh bits of the MA byte) identify the phase of the multiframe (00, 01, 10, or 11). The
timing marker bit (eighth bit of the MA byte) contains the timing source indicator bit indicated by the multiframe
indicator bits (first, second, third, or fourth bit respectively). The four timing source indicator bits are extracted from
the multiframe, integrated, and stored in four register bits with unstable and change indications.
The NR byte is integrated and stored in a register along with a change indication, it is sent to the receive FEAC
controller, and it can be sent to the receive HDLC controller. The byte sent to the receive HDLC controller is
programmable (NR or GC).
The GC byte is integrated and stored in a register along with a change indication, and can be sent to the receive
HDLC controller. The byte sent to the receive HDLC controller is programmable (NR or GC).
10.6.8.10 Receive G.832 Downstream AIS Generation
Downstream G.832 E3 AIS can be automatically generated on an OOF, LOS, or AIS condition or manually
inserted. If automatic downstream AIS is enabled, downstream AIS is inserted when an LOS, OOF, or AIS
condition is declared. Automatic downstream AIS is programmable (on or off). If manual downstream AIS insertion
is enabled, downstream AIS is inserted. Manual downstream AIS insertion is programmable (on or off).
Downstream AIS is removed when all OOF, LOS, and AIS conditions are terminated and manual downstream AIS
insertion is disabled. RPDT will be forced to all ones during downstream AIS.
10.7 HDLC Overhead Controller
10.7.1 General Description
The DS3170 device contains a built-in HDLC controller with 256 byte FIFOs for insertion/extraction of DS3 PMDL,
G.751 Sn bit and G.832 NR/GC bytes.
The HDLC Overhead Controller demaps HDLC overhead packets from the DS3/E3 data stream in the receive
direction and maps HDLC packets into the DS3/E3 data stream in the transmit direction.
The receive direction performs packet processing and stores the packet data in the FIFO. It removes packet data
from the FIFO and outputs the packet data to the microprocessor via the register interface.
The transmit direction inputs the packet data from the microprocessor via the register interface and stores the
packet data in the FIFO. It removes the packet data from the FIFO and performs packet processing.
EXPECTED
XXX
XXX
XXX
XXX
000
000
000
001
001
001
RECEIVED
XXX
XXX
XXX
YYY
000
001
000
001
000
001
≠
YYY.
96 of 230
Mismatch
Mismatch
Mismatch
Mismatch
Mismatch
STATUS
Match
Match
Match
Match
Match
DS3170 DS3/E3 Single-Chip Transceiver