PRELIMINARY
PM4318 OCTLIU
DATASHEET
PMC- 2001578
ISSUE 3
OCTAL E1/T1/J1 LINE INTERFACE DEVICE
Pin Name
Type
Pin
No.
Function
SRCLK
I/O
A3
Serial PROM Clock (SRCLK). When operating as a Serial PROM
master (SRCASC tied low), the SRCLK pin functions as an output
and generates a clock for the serial PROM. When operating as a
Serial PROM slave (SRCASC tied high), the SRCLK pin functions
as an input and is connected to the SRCCLK output of an
OCTLIU device upstream in the serial PROM cascade.
SRDI
Output
Input
D6
B4
Serial PROM Data In (SRDI). When operating as a Serial PROM
master (SRCASC tied low), the SRDI output is used to send read
commands to the serial PROM. When operating as a Serial
PROM slave (SRCASC tied high), SRDI is unused.
SRDI is updated on the falling edge of SRCLK.
SRDO
Serial PROM Data Out (SRDO). When operating as a Serial
PROM master (SRCASC tied low), the SRDO input receives data
from the serial PROM. When operating as a Serial PROM slave
(SRCASC tied high), the SRDO input receives data from the
SRCDO output of an OCTLIU device upstream in the serial
PROM cascade.
SRDO is sampled on the rising edge of SRCLK.
SRCEN
Output
Output
C5
A4
Serial PROM Cascade Enable (SRCEN). The SRCEN output is
asserted when valid data is being output on SRCDO.
SRCEN is updated on the falling edge of SRCCLK.
SRCCLK
Serial PROM Cascade Clock (SRCCLK). When operating as a
Serial PROM master (SRCASC tied low), the SRCCLK output is a
copy of the SRCLK output. When operating as a Serial PROM
slave (SRCASC tied high), the SRCCLK output is a copy of the
SRCLK input.
SRCDO
Output
Input
B5
C6
Serial PROM Cascade Data Out (SRCDO). The SRCDO output
is a buffered, retimed copy of the SRDO input.
SRCDO is updated on the falling edge of SRCCLK.
SRCODE
Serial PROM Code (SRCODE). The SRCODE input provides a
means for controlling the execution of configuration instructions
stored in the serial PROM. Instructions can be coded to execute
only if SRCODE is logic 0, only if SRCODE is logic 1 or
unconditionally. The SRCODE input thus allows the selection of
two different configuration sequences within a single PROM load.
This could be used, for example, to store two configurations for
T1 and E1 operation within one serial PROM.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
26
PMC [ PMC-SIERRA, INC ]
