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XRT94L33
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
Rev.1.2.0.
325
2.2.9.5.10
SUPPORT/HANDLING OF THE LINE DCC (D4 THROUGH D12) BYTE
2.2.9.5.11
SUPPORT/HANDLING OF THE S1 BYTE
The Transmit STS-3c TOH Processor block permits the user to control the value of the S1 byte, which is to be
transmitted via the “outbound” STS-3c data-stream, by either or the following options.
Setting and controlling the S1 byte via software
Setting and controlling the S1 byte via the “TxPOH Input Port”
The details and instructions for using either of these features are presented below.
2.2.9.5.11.1
Setting and Controlling the outbound S1 byte via Software
The Transmit STS-3c TOH Processor block permits the user to specify the contents of the E1 byte within the
outbound STS-3c data-stream via software command.
The user can configure the Transmit STS-3c TOH Processor block to accomplish this by performing the
following steps.
STEP 1 – Write the value “1” into Bit 2 (S1 Insert Method) within the “Transmit STS-3c Transport –
SONET Transmit Control Register – Byte 1, as depicted below.
Transmit STS-3Transport – SONET Transmit Control Register – Byte 1 (Address = 0x1902)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Reserved
E2 Insert
Method
E1 Insert
Method
F1 Insert
Method
S1 Insert
Method
K1K2 Insert
Method
M0M1 Insert
Method[1]
R/O
R/W
0
X
1
X
The step configures the Transmit STS-3c TOH Processor block to read out the contents of the “Transmit
STS-3c Transport – S1 Byte Value Register, and load this value into the S1 byte position within each
outbound STS-3c data-stream.
STEP 2 – Write the desired byte values (for the outbound S1 byte) into the “Transmit STS-3c
Transport – S1 Byte Value Register.
The bit-format for this register is presented below.
Transmit STS-3 Transport – Transmit S1 Byte Value Register (Address = 0x193B)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Transmit_S1_Byte_Value[7:0]
R/W
0
2.2.9.5.11.2
Setting and Controlling the outbound S1 byte via “TxPOH Input Port”
The Transmit STS-3c TOH Processor block permits the user to specify the contents of the S1 byte within the
“outbound” STS-3c data-stream via the data applied to the “TxPOH_n” input port.
The user can configure the Transmit STS-3c TOH Processor block to accomplish this by performing the
following steps.
STEP 1 – Write the value “1” into Bit 4 (STS-3c TOH Insert) within the “Mapper Control Register – Byte 2”, as
depicted below.