VSC6134
Datasheet
2.7.5.13
OPUk Payload Structure Identifier (PSI)
Updating the OPUk PSI byte is controlled (enabled or disabled) using microprocessor-programmable
bits ADD/DROP_PSICTRL[1:0]. Decoding for ADD/DROP_PSICTRL[1:0] is shown in the following
table.
Table 31. ADD/DROP_PSICTRL Decoding
ADD/DROP_PSICTRL
Function
00
The PSI byte is sourced from microprocessor accessible registers
ADD/DROP_PSI_GEN[127:0][15:0].
01
10
The PSI byte is sourced from the FPGA1.
The PSI byte is sourced from the received data in the OTUk to FEC or FEC loopback
modes respectively.
11
Reserved.
1. In the non-FPGA mode, zeros are inserted for the reserved bytes.
ADD/DROP_PSI_GEN[127:0][15:0] is implemented as a stack and is accessible through a single
microprocessor address. The ADD/DROP_PSI_GEN_PNT[6:0] pointer points to the
ADD/DROP_PSI_GEN[15:0] location which is written to or read from the stack by the next
microprocessor write/read to ADD/DROP_PSI_GEN[15:0].
ADD/DROP_PSI_GEN_PNT[6:0] can be written to or read from the microprocessor.
ADD/DROP_PSI_GEN_PNT[6:0] is incremented automatically after each access to
ADD/DROP_PSI_GEN[15:0].
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VMDS-10185 Revision 4.0
July 2006
VITESSE [ VITESSE SEMICONDUCTOR CORPORATION ]
