xrt94l33 Exar Corporation, xrt94l33 Datasheet - Page 302

• Manufacturer Part Number: xrt94l33
• Description: Multi-channel, Multi-function Device Aggregates 3 Ds3/e3/sts-1 Into Oc3/stm-1
• Manufacturer: Exar Corporation

XRT94L33
Rev.1.2.0.
How Automatic Transmission of the RDI-L Indicator Works
Consider that the Transmit STS-3 TOH Processor block (within a given channel) has been configured to
automatically transmit the RDI-L indicator whenever the corresponding Receive STS-3 TOH Processor block
detects an LOS condition. Figure 59 presents a simple illustration of the Transmit STS-3 TOH Processor and
Receive STS-3 TOH Processor block pair.
Processor block is not declaring the LOS condition.
Figure 59 Illustration of a Transmit STS-3 TOH Processor and Receive STS-3 TOH Processor block
pair, when LOS is not being declared.
As a consequence, the Transmit STS-3 TOH Processor block will, in-turn, not transmit the RDI-L indicator (by
setting bits 6, 7 and 8, of the K2 byte, to a value other than [1, 1, 0]).
Figure 57 presents a different illustration of the Transmit STS-3 TOH Processor and Receive STS-3 TOH
Processor blocks. In this case, the Receive STS-3 TOH Processor block is now declaring the LOS condition.
As a consequence, the Transmit STS-3 TOH Processor block will, in-turn, transmit the RDI-L indicator, by
setting bits 6, 7 and 8 (of the K2 byte), within the outbound STS-3 signal to the value [1, 1, 0].
Figure 60 Illustration of the Transmit STS-3 TOH Processor block transmitting the RDI-L indicator to
the Remote Terminal coincident with the Receive STS-3 TOH Processor block declaring an LOS
condition.
2.2.9.5.4
The Transmit STS-3 TOH Processor block can be configured to transmit the REI-L indicator either (1)
automatically, (2) upon software command, or (3) via the TxPOH External Input Port, as described below.
2.2.9.5.4.1
The user can configure the Transmit STS-3 TOH Processor block to automatically transmit the REI-L indicator
whenever the corresponding Receive STS-3c TOH Processor block detects at least one B2 byte error.
The user can configure the Transmit STS-3 TOH Processor block to automatically transmit the REI-L
indicator, in response to detection of B2 byte errors, by executing the following steps.
STEP 1 – Write the value “0” into Bit 0 (M0M1 Insert Method[1]) within the “Transmit STS-3 Transport
– SONET Transmit Control Register – Byte 1”; as depicted below.
Transmit STS-3Transport – SONET Transmit Control Register – Byte 1 (Address = 0x1902)
B
R/O
IT
0
7
Reserved
TRANSMISSION OF THE REI-L INDICATOR
Configuring the Transmit STS-3 TOH Processor Block to automatically transmit the
REI-L Indicator
B
R/O
IT
0
6
E2 Insert
Method
B
R/W
IT
0
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
5
E1 Insert
Method
B
R/W
IT
0
Further, this figure indicates that the Receive STS-3 TOH
4
302
F1 Insert
Method
B
R/W
IT
0
3
S1 Insert
Method
B
R/W
IT
0
2
K1K2 Insert
Method
B
R/W
IT
0
1
xr
M0M1 Insert
Method[1]
B
R/W
IT
0
0