PM5357 Datasheet, PDF (360/432 Pages) PMC-Sierra, Inc – 622 Mbit/s ATM and Packet Over SONET Physical Layer Device

PRODUCTION
S/UNI-622-POS
DATASHEET
PMC-1980911
ISSUE 5
PMC-Sierra, Inc.
PM5357
S/UNI-622-POS
SATURN USER NETWORK INTERFACE (622-POS)
Figure 24: A 63 Byte Packet Data Structure
Byte 1
Byte 2
Byte 3
Byte 4
Byte 63
A 63 Byte Frame
Both the start of the packet and the end of the packet must be identified by the
TSOP/RSOP and TEOP/REOP signals. When the first section of a packet is
transferred over the interface, the TSOP/RSOP signals will be high for Byte 1 of
the packet only.
13.4 Setting ATM Mode of Operation
The following sequence of operation should be used to prepare the device for the
ATM operation.
1- Input pin POS_ATMB (Y21) should be tied low to enable ATM
operation. This pin can be overridden in software by writing a logic one
to the RMOVR bit (Register 0x90) and TMOVR bit (Register 0x92).
Writing a logic zero to the RPOS_ATMB bit (Register 0x90) and the
TPOS_ATMB bit (Register 0x92) can then be used to enable ATM
operation.
When using the software override feature, these bits must be set after
step (2), as resetting the device restores the registers to their default
values. This feature is useful for building a single PHY card that can
be configured in software as a POS or ATM card.
2- Reset the device. This can be done by asserting the RSTB pin or
setting the RESET bit in the Master Reset and ID Register (Register
0x00).
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA INC., AND ITS CUSTOMERS’ INTERNAL USE
355