PRELIMINARY
PM4318 OCTLIU
DATASHEET
PMC- 2001578
ISSUE 3
OCTAL E1/T1/J1 LINE INTERFACE DEVICE
Pin Name
Type
Pin
No.
Function
Timing Options Control
XCLK
Input
D9
Crystal Clock Input (XCLK). This signal provides a stable, global
timing reference for the OCTLIU internal circuitry via an internal
clock synthesizer. XCLK is a nominally jitter free clock at
1.544 MHz in T1 mode and 2.048 MHz in E1 mode.
In T1 mode, a 2.048 MHz clock may be used as a reference.
When used in this way, however, the intrinsic jitter specifications
in AT&T TR62411 may not be met.
RSYNC/ICLK_OUT
Output
D8
Recovered Clock Synchronization Signal (RSYNC). This output
signal is the recovered, jitter attenuated, receiver line rate clock
(1.544 or 2.048 MHz) of one of the eight T1 or E1 channels or,
optionally, the recovered, jitter attenuated clock synchronously
divided by 193 (T1 mode) or 256 (E1 mode) to create a 8 kHz
timing reference signal. The default is to source RSYNC from
octant #1.
When the OCTLIU is in a loss of signal state, RSYNC is derived
from the XCLK input or, optionally, is held high.
RSYNC shares the same pin as the ICLK_OUT output. RSYNC is
selected when SBI2CLK is tied low.
Alarm Interface
LOS
Output
A5
Loss of Signal Alarm (LOS). This signal outputs the LOS status
of the 8 LIU octants in a serial format which repeats every 8
XCLK cycles. The presence of the LOS status for LIU #1 on this
output is indicated by the LOS_L1 output pulsing high. On the
following XCLK cycle, the LOS status for LIU #2 is output, then
LIU #3, and so on.
This signal is intended for use in Hardware Only mode. When the
microprocessor interface is enabled, the status of the LOS alarm
can also be determined by reading the LOSV bit in the CDRC
Interrupt Status register.
LOS is updated on the falling edge of XCLK.
LOS_L1
Output
C7
Loss of Signal LIU #1 indicator (LOS_L1). This signal is pulsed
high for one XCLK cycle every 8 XCLK cycles and indicates that
the LOS status for LIU #1 is being output on LOS.
LOS_L1 is updated on the falling edge of XCLK.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE
22
PMC [ PMC-SIERRA, INC ]
