
XRT86SH328
PRELIMINARY
152
28-CHANNEL DS1/E1 FRAMER/LIU WITH DS3 MUX & VT-MAPPER - SONET APPLICATIONS
REV. P1.0.6
Decrementing event at the remote terminal.
`
Writing a 0 to 1 transition into this bit-field causes the following to happen.
A negative-stuff will occur (e.g., a single payload byte will be inserted into the H3 byte position within the
outbound STS-1 or STS-3 Data stream).
The D bits, within the H1 and H2 bytes will be inverted (to denote a Decrementing Pointer Adjustment event).
The contents of the H1 and H2 bytes will be decremented by 1, and will be used as the new pointer from this
point on.
N
OTE
:
Once the user writes a 1 into this bit-field, the XRT86SH328 will automatically clear this bit-field. Hence, there
is no need to subsequently reset this bit-field to 0.
BITt 2 - Insert Positive Stuff
This READ/WRITE bit-field is used to configure the Transmit STS-1/STS-3 POH and TOH Processor blocks to insert a
positive-stuff into the outbound STS-1 or STS-3 Data stream. This command, in-turn will cause a Pointer Incrementing
event at the remote terminal.
`
Writing a 0 to 1 transition into this bit-field causes the following to happen.
A positive-stuff will occur (e.g., a single stuff-byte will be inserted into the STS-1 or STS-3 Data-stream,
immediately after the H3 byte position within the outbound STS-1 or STS-3 Data stream).
The I bits, within the H1 and H2 bytes will be inverted (to denote a Incrementing Pointer Adjustment event).
The contents of the H1 and H2 bytes will be incremented by 1, and will be used as the new pointer from this
point on.Note
N
OTE
:
Once the user writes a 1 into this bit-field, the XRT86SH328 will automatically clear this bit-field. Hence, there
is no need to subsequently reset this bit-field to 0.
BITt 1 - Insert Continuous NDF Events
This READ/WRITE bit-field is used configure the Transmit STS-1/STS-3 POH and TOH Processor blocks to
continuously insert a New Data Flag (NDF) pointer adjustment into the outbound STS-1 or STS-3 Data stream.
As the Transmit STS-1/STS-3 POH and TOH Processor blocks insert the NDF event into the STS-1 or STS-3 Data
stream, it will proceed to load in the contents of the Transmit STS-1/STS-3 POH Arbitrary H1 Pointer and Transmit STS-
1/STS-3 POH Arbitrary H2 Pointer registers into the H1 and H2 bytes (within the outbound STS-1 or STS-3 Data
stream).
`
0 - Configures the Transmit STS-1/STS-3 TOH and POH Processor blocks to not continuously insert NDF events into
the outbound STS-1 or STS-3 Data stream.
`
1- Configures the Transmit STS-1/STS-3 TOH and POH Processor blocks to continuously insert NDF events into the
outbound STS-1 or STS-3 Data stream.
BITt 0 - Insert Single NDF Event
This READ/WRITE bit-field is used to configure the Transmit STS-1/STS-3 POH and TOH Processor blocks to insert a
New Data Flag (NDF) pointer adjustment into the outbound STS-1 or STS-3 Data stream.
`
Writing a 0 to 1 transition into this bit-field causes the following to happen
The N bits, within the H1 byte will set to the value 1001
The ten pointer-value bits (within the H1 and H2 bytes) will be set to new pointer value per the contents within
the Transmit STS-1/STS-3 POH - Arbitrary H1 Pointer and Transmit STS-1/STS-3 POH Arbitrary H2 Pointer
registers (Address Location= 0x07BF and 0xN9C3).
N
OTE
:
Afterwards, the N bits will resume their normal value of 0110 and this new pointer value will be used as the new
pointer from this point on. Once the user writes a 1 into this bit-field, the XRT86SH328 will automatically clear
this bit-field. Hence, there is no need to subsequently reset this bit-field to 0.