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XRT94L33
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
Rev.1.2.0.
269
2.2.8.3.4
TRANSMISSION OF PATH TRACE MESSAGES VIA THE J1 BYTE
The Transmit SONET POH Processor block permits the user to transmit Path Trace Messages to the remote
PTE via the J1 byte. The Transmit SONET POH Processor block permits the user to accomplish this by
either of the following options.
Automatically set the J1 byte (within each outbound STS-1 SPE) to “0x00”
Set and control the outbound J1 byte via on-chip register
Set and control the outbound J1 byte via external input pin
Use the “Transmit Path Trace Message” buffer
The details and instructions for using either of these features are presented below.
2.2.8.3.4.1
Automatically setting the J1 byte (within each outbound STS-1 SPE) to “0x00”
The XRT94L33 permits the user to configure each of the four (4) Transmit SONET POH Processor blocks to
automatically set the contents of the J1 byte (within each outbound STS-1 SPE) to “0x00”.
The user can accomplish this by writing the value “[0, 0]” into Bits 1 and 0 (J1 Type[1:0]) within the
appropriate “Transmit SONET Path – Transmit J1 Control” Register; as depicted below.
Transmit SONET Path – Transmit J1 Control” Register (Address = 0xN9BB)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Unused
J1 Message Length[1:0]
J1 Type[1:0]
R/O
R/W
0
X
0
Once the user executes this step, then the corresponding Transmit SONET POH Processor block(s) will be
configured to automatically set the J1 byte (within each outbound STS-1 SPE) to the value “0x00”.
2.2.8.3.4.2
Using the “Transmit Path Trace Message” Buffer
The XRT94L33 contains a total of four (4) “Transmit Path Trace Message Buffers (one for each “Transmit
SONET POH Processor Block, within the device).
The address location of the “Transmit Path Trace Message” buffer, for each of the four Transmit SONET POH
Processor blocks is presented below.
Table 15: Address Locations of the Transmit Path Trace Message Buffers within the XRT94L33
TRANSMIT SONET POH PROCESSOR BLOCK -
CHANNEL
ADDRESS LOCATION OF THE TRANSMIT PATH TRACE
MESSAGE BUFFER
0
0x1D00 – 0x1D3F
1
0x2D00 – 0x2D3F
2
0x3D00 – 0x3D3F
3
0x4D00 – 0x4D3F
If the user wishes to use the “Path Trace Message” buffer as the means to load and transmit the “Path Trace
Message” to the remote PTE, then the following steps must be executed.