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STANDARD PRODUCT
PM4351 COMET
DATA SHEET
PMC-1970624
ISSUE 10
COMBINED E1/T1 TRANSCEIVER
PROPRIETARY AND CONFIDENTIAL
24
Pin No.
Pin Name
Type
-RI
-NI
Function
TFP
Digital
Output
7
D1
Transmit Digital Frame Pulse (TFP). When the transmit digital line interface is
enabled, the TFP output indicates frame alignment of the line side transmitted
PCM stream (TDAT). This mode may be used in applications not requiring a
physical T1/E1 interface (e.g. interfacing to HDSL transceivers). TFP is
updated on the either the rising or falling (default) edge of TCLKO.
Table 4
- Receive Line Interface (4 pins)
Pin No.
Pin Name
Type
-RI
-NI
Function
RXTIP
Analog
Input
63
C7
Receive Analog Positive Pulse (RXTIP). When the analog receive line
interface is enabled, RXTIP samples the received line pulse signal from an
external isolation transformer. RXTIP is normally connected directly to the
positive lead of the receive transformer secondary.
RXRING
Analog
Input
64
A8
Receive Analog Negative Pulse (RXRING). When the analog receive line
interface is enabled, RXRING samples the received line pulse signal from an
external isolation transformer. RXRING is normally connected directly to the
negative lead of the receive transformer secondary.
RDAT
Input
57
E8
Receive Digital Line Data (RDAT). When the digital receive interface is
enabled, the RDAT input samples the line side recovered NRZ PCM data
stream. This mode may be used in applications not requiring a physical T1/E1
interface (e.g. interfacing to HDSL transceivers). In digital mode, clock and
data recovery is disabled. RDAT is sampled on the rising (default) or falling
edge of RCLKI.
RCLKI
Input
56
D9
Receive Digital Line Clock (RCLKI). When the digital receive line interface is
enabled, the externally recovered line rate clock must be provided on RCLKI.
This mode may be used in applications not requiring a physical T1/E1 interface
(e.g. interfacing to HDSL transceivers). RCLKI samples the receive PCM
stream (RDAT) on its rising (default) or falling edge.
Table 5
- Timing Options Control (5 pins)
Pin No.
Pin Name
Type
-RI
-NI
Function
PIO
I/O
59
B9
Programmable I/O. PIO is an input/output pin controlled by a COMET register
bit. As an output, the PIO bit can, under software control, be used to configure
external circuitry dependent upon the mode of the COMET device. As an
input, the state of the PIO pin can be read via a register bit.