PM7344 S/UNI-MPH
DATA SHEET
PMC-950449
ISSUE 6
MULTI-PHY USER NETWORK INTERFACE
13
FUNCTIONAL TIMING
Figure 18
- Arbitrary Rate Transmit Interface
TCLKI
TFPI/TOHI
TCLKO
TDN/TOHO[x]
TDP/TDD[x]
BITN
TSOH BITN+5 BITN+6 BITN+7
BAITTN+M1 CBIeTlNl+D2aBtaITN+3 BITN+4 TOSOvHerhead
ATM Cell Data
The S/UNI-MPH is configured to select the arbitrary transmit interface. TOHO
marks the location of the transmission system overhead placeholder bits (TSOH)
in the TDD stream. The delay between TOHI and TOHO is fixed to be 2.5 clock
periods starting at the rising TCLKI edge where TOHI is sampled and finishing at
the falling TCLKO[x] edge where TOHO[x] is generated. It should be noted that
the outputs are clocked out on TCLKO[x] which is a flow-through version of
TCLKI and which could be significantly delayed from TCLKI. The active polarity
(here shown as active high) of the TOHI and TOHO signals can be inverted using
the TOHINV and TDNINV bits in the Transmit Interface Configuration register.
The active edge that is used to sample TFPI (here shown as the rising edge) as
well as update TOHO[x] and TDD[x] can be inverted using the TFALL and TRISE
bits in the Transmit Interface Configuration register. The octet alignment of the
bit position labeled "BITM+1" in the timing diagram is controlled by the TOCTA bit
in the Transmit Interface Configuration register.
Figure 19
- Arbitrary Rate Receive Interface
RCLKI[x]
RDN/ROH[x]
RDP/RDD[x] BITN BITN+1 BITN+2 BITN+3 TSOH TSOH BITN+4 BITN+5 BITN+6 BITN+7
Overhead
ATM Cell Data
ATM Cell Data
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
225
PMC [ PMC-SIERRA, INC ]
