XRT79L74IB View Datasheet(PDF) - Exar Corporation
Part Name
Description
MFG CO.
'XRT79L74IB' PDF : 70 Pages View PDF
XRT79L74
REV. P1.0.0
PRELIMINARY
4 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC
TABLE OF CONTENTS
HARDWARE MANUAL ......................................................................................................1
GENERAL FEATURES:......................................................................................................................................1
Line Interface Unit ....................................................................................................................................................... 1
DS3/E3 Framer............................................................................................................................................................ 1
ATM/PPP PROTOCOL PROCESSOR........................................................................................................................ 1
Transmit Cell Processing............................................................................................................................................. 1
Receive Cell Processing.............................................................................................................................................. 1
Transmit Packet Processing ........................................................................................................................................ 2
Receive Packet Processing ......................................................................................................................................... 2
Utopia/ System Interface ............................................................................................................................................. 2
Serial Interface ............................................................................................................................................................ 2
APPLICATIONS ...........................................................................................................................................2
FIGURE 1. BLOCK DIAGRAM OF THE XRT79L74 ............................................................................................................................... 2
PRODUCT ORDERING INFORMATION ................................................................................................................2
PIN DESCRIPTIONS.........................................................................................................................................4
MICROPROCESSOR INTERFACE .......................................................................................................................4
TEST AND DIAGNOSTIC ...................................................................................................................................6
GENERAL PURPOSE INPUT AND OUTPUT PINS.................................................................................................7
TRANSMIT SYSTEM SIDE INTERFACE PINS.......................................................................................................7
RECEIVE SYSTEM SIDE INTERFACE PINS.......................................................................................................24
TRANSMIT LINE SIDE SIGNALS ......................................................................................................................40
RECEIVE LINE SIDE SIGNALS ........................................................................................................................42
ELECTRICAL CHARACTERISTICS ................................................................................45
AC ELECTRICAL CHARACTERISTIC INFORMATION ..................................................45
MICROPROCESSOR INTERFACE TIMING FOR REVISION A SILICON ......................................................45
MICROPROCESSOR INTERFACE TIMING - ASYNCHRONOUS INTEL MODE.................................................... 45
TABLE 1: DC ELECTRICAL CHARACTERISTICSS..................................................................................................................... 45
Applies to all TTL-Level Input and CMOS Level Output pins - Ambient Temperature = 25°C .................................. 45
FIGURE 2. ASYNCHRONUS MODE 1 - INTEL TYPE PROGRAMMED I/O TIMING (WRITE CYCLE) ............................................................ 45
FIGURE 3. ASYNCHRONUS MODE 1 - INTEL TYPE PROGRAMMED I/O TIMING (READ CYCLE) ............................................................. 46
TABLE 2: TIMING INFORMATION FOR THE MICROPROCESSOR INTERFACE, WHEN CONFIGURED TO OPERATE IN THE INTEL ASYNCHRONOUS
MODE ............................................................................................................................................................................ 46
MICROPROCESSOR INTERFACE TIMING - ASYNCHRONOUS MOTOROLA (68K)
MODE................................................................................................................................ 47
FIGURE 4. ASYNCHRONUS MODE 2 - MOTOROLA 68K PROGRAMMED I/O TIMING (WRITE CYCLE) .................................................... 47
FIGURE 5. ASYNCHRONUS MODE 2 - MOTOROLA 68 PROGRAMMED I/O TIMING (READ CYCLE) ........................................................ 47
MICROPROCESSOR INTERFACE TIMING - POWER PC 403 SYNCHRONOUS MODE48
TABLE 3: TIMING INFORMATION FOR THE MICROPROCESSOR INTERFACE WHEN CONFIGURED TO OPERATE IN THE MOTOROLA (68K) ASYN-
CHRONOUS MODE........................................................................................................................................................... 48
FIGURE 6. SYNCHRONOUS MODE 3 - IBM POWERPC 403 INTERFACE TIMING (WRITE CYCLE) ......................................................... 48
FIGURE 7. SYNCHRONOUS MODE 3 - IBM POWERPC 403 INTERFACE TIMING (READ CYCLE)........................................................... 49
TABLE 4: TIMING INFORMATION FOR THE MICROPROCESSOR INTERFACE, WHEN CONFIGURED TO OPERATE IN THE IBM POWER PC403
MODE ............................................................................................................................................................................ 49
DS3/E3 LIU INTERFACE - LINE SIDE ELECTRICAL CHARACTERISTIC INFORMATION
50
E3 LINE SIDE PARAMETERS .........................................................................................................................50
FIGURE 8. PULSE MASK FOR E3 (34.368MBPS) INTERFACE AS PER ITU-T G.703 ........................................................................... 50
TABLE 5: E3 TRANSMITTER LINE SIDE OUTPUT AND RECEIVER LINE SIDE INPUT SPECIFICATIONS........................................................ 50
DS3 LINE SIDE PARAMETERS .......................................................................................................................51
FIGURE 9. BELLCORE GR-499-CORE PULSE TEMPLATE REQUIREMENTS FOR DS3 APPLICATIONS.................................................. 51
TABLE 6: DS3 PULSE MASK EQUATIONS ........................................................................................................................................ 52
TABLE 7: DS3 TRANSMITTER LINE SIDE OUTPUT AND RECEIVER LINE SIDE INPUT SPECIFICATIONS (GR-499) ................................. 52
TRANSMIT UTOPIA INTERFACE....................................................................................53
FIGURE 10. TIMING DIAGRAM FOR THE TRANSMIT UTOPIA INTERFACE BLOCK ................................................................................ 53
TABLE 8: TIMING INFORMATION FOR THE TRANSMIT UTOPIA INTERFACE BLOCK ............................................................................. 53
TRANSMIT PAYLOAD DATA INPUT INTERFACE.........................................................54
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