Rainbow Electronics DS2153Q User Manual

DS2153Q
DS2153Q
E1 Single–Chip Transceiver
Complete E1(CEPT) PCM–30/ISDN–PRI transceiver
functionality
Onboard line interface for clock/data recovery and
waveshaping
32–bit or 128–bit jitter attenuator
Generates line build–outs for both 120 ohm and 75
ohm lines
Frames to FAS, CAS, and CRC4 formats
Dual onboard two–frame elastic store slip buffers that
can connect to backplanes up to 8.192 MHz
8–bit parallel control port that can be used on either
multiplexed or non–multiplexed buses
Extracts and inserts CAS signaling
Detects and generates Remote and AIS alarms
Programmable output clocks for Fractional E1, H0,
and H12 applications
Fully independent transmit and receive functionality
Full access to both Si and Sa bits
Three separate loopbacks for testing
Large counters for bipolar and code violations, CRC4
code word errors, FAS errors, and E bits
Pin compatible with DS2151Q T1 Single–Chip Trans-
ceiver
5V supply; low power CMOS
Industrial grade version (–40°C to +85°C) available
(DS2153QN)
DESCRIPTION
The DS2153Q T1 Single–Chip Transceiver (SCT) con­tains all of the necessary functions for connection to E1 lines. The onboard clock/data recovery circuitry coverts the AMI/HDB3 E1 waveforms to a NRZ serial stream.
PIN ASSIGNMENT
FUNCTIONAL BLOCKS
FRAMER
ELASTIC STORES
LINE INTERFACE
LONG & SHORT HAUL
PARALLEL CONTROL
PORT
DALLAS
DS2153Q
E1 SCT
ALE
WR
RLINK
RLCLK
DVSS RCLK
RCHCLK
RSER
RSYNC
RLOS/LOTC
SYSCLK
The DS2153 automatically adjusts to E1 22 AWG (0.6 mm) twisted–pair cables from 0 to 1.5 KM. The device can generate the necessary G.703 waveshapes for both 75 ohm and 120 ohm cables. The onboard jitter
ACTUAL SIZE OF
44–PIN PLCC
CSRDAD7
AD6
AD5
AD4
AD3
AD2
65432
7 8 9 10 11 12 13 14 15 16 17
1819202122232425262728
ACLKI
RCHBLK
BTS
RTIP
1
RVDD
RRING
4443424140
RVSS
XTAL1
AD1
XTAL2
AD0
39 38 37 36 35 34 33 32 31 30 29
INT1
TCHCLK
TSER TCLK DVDD TSYNC TLINK TLCLK TCHBLK TRING TVDD TVSS TTIP
INT2
Copyright 1995 by Dallas Semiconductor Corporation. All Rights Reserved. For important information regarding patents and other intellectual property rights, please refer to Dallas Semiconductor data books.
022697 1/48
DS2153Q
attenuator (selectable to either 32 bits or 128 bits) can be placed in either the transmit or receive data paths. The framer locates the frame and multiframe bound­aries and monitors the data stream for alarms. It is also used for extracting and inserting signaling data, Si, and Sa–bit information. The device contains a set of 71 8–bit internal registers which the user can access and control the operation of the unit. Quick access via the parallel control port allows a single micro to handle many E1 lines. The device fully meets all of the latest E1 specifications including ITU G.703, G.704, G.706, G.823, and I.431 as well as ETSI 300 011 and 300 233.
TABLE OF CONTENTS
1. Introduction
2. Parallel Control Port
3. Control and Test Registers
4. Status and Information Registers
5. Error Count Registers
6. Sa Data Link Control and Operation
7. Signaling Operation
8. Transmit Idle Registers
9. Clock Blocking Registers
10. Elastic Store Operation
11. Additional (Sa) and International (Si) Bit Operation
12. Line Interface Control Function
13. Timing Diagrams, Synchronization Flowchart, and Transmit flow Diagram
14. DC and AC Characteristics
1.0 INTRODUCTION
The analog AMI waveform off of the E1 line is trans­former coupled into the RRING and RTIP pins of the DS2153Q. The device recovers clock and data from the analog signal and passes it through the jitter attenuation mux to the receive side framer where the digital serial stream is analyzed to locate the framing pattern. If
needed, the receive side elastic store can be enabled in order to absorb the phase and frequency differences between the recovered E1 data stream and an asynch­ronous backplane clock which is provided at the SYSCLK input.
The transmit side of the DS2153Q is totally independent from the receive side in both the clock requirements and characteristics. The transmit formatter will provide the necessary data overhead for E1 transmission. Once the data stream has been prepared for transmission, it is sent via the jitter attenuation mux to the waveshaping and line driver functions. The DS2153Q will drive the E1 line from the TTIP and TRING pins via a coupling trans­former.
Reader’s Note
This data sheet assumes a particular nomenclature of the E1 operating environment. There are 32 8–bit time­slots in E1 systems which are numbered 0 to 31. Time­slot 0 is transmitted first and received first. These 32 timeslots are also referred to as channels with a num­bering scheme of 1 to 32. Timeslot 0 is identical to chan­nel 1, timeslot 1 is identical to channel 2, and so on. Each timeslot (or channel) is made up of eight bits which are numbered 1 to 8. Bit number 1 is the MSB and is transmitted first. Bit number 8 is the LSB and is trans­mitted last. Throughout this data sheet, the following abbreviations will be used:
FAS Frame Alignment Signal CAS Channel Associated Signaling MF Multiframe Si International Bits CRC4 Cyclical Redundancy Check CCS Common Channel Signaling Sa Additional bits E–bit CRC4 Error bits
022697 2/48
DS2153Q BLOCK DIAGRAM Figure 1–1
RCLK
RLINK
RLCLK
RCHBLK
Sa Bit
RCHCLK
Extraction
Framer
Receive Side
RSER
Timing
Control
Signaling Extraction
FAS Error Count
E Bit Count
CRC4 Error Count
Alarm Detection
Synchronizer BPV Counter
HDB3 Decoder
SYSCLK
RSYNC
Store
Elastic
TCLK
Loss of
TCLK Detect
mux
FAS Word Insertion
Si Bit Insertion
E Bit Insertion
Sa Bit Insertion Signaling Insertion Idle Code Insertion
CRC4 Generation
Transmit Side Formatter
AIS Generation
TSER
Store
Elastic
clock
data
sync
HDB3 Encode
TSYNC
TCHCLK
Timing
Control
TCHBLK
TLINK
Sa
Insert
DS2153Q
TLCLK
Logic
ACLKI XTAL1 XTAL2 RLOS
XTAL/VCO/PLL
32.768 MHz
Framer Loopback
Remote Loopback
Data
Clock/
Peak
Filter
RRING
Recovery
Detect
RTIP
Jitter Attenuation Mux
Local Loopback
Wave
Line
TRING
Shaping
Drivers
TTIP
(can be placed in either the transmit or receive paths)
(routed to all blocks)
Parallel Control Port
CS WR(R/W) RD(DS) ALE(AS) AD0 – AD7 INT1/INT2
BTS
022697 3/48
DS2153Q
PIN DESCRIPTION Table 1–1
PIN SYMBOL TYPE DESCRIPTION
1 2 3 4
5 RD(DS) I Read Input (Data Strobe). 6 CS I Chip Select. Must be low to read or write the port. 7 ALE(AS) I Address Latch Enable (Address Strobe). A positive going edge serves to
8 WR(R/W) I Write Input (Read/Write). 9 RLINK O Receive Link Data. Outputs the full receive data stream including the Sa
10 RLCLK O Receive Link Clock. 4 KHz to 20 KHz demand clock for the RLINK output;
11 DVSS Digital Signal Ground. 0.0 volts. Should be tied to local ground plane. 12 RCLK O Receive Clock. Recovered 2.048 MHz clock. 13 RCHCLK O Receive Channel Clock. 256 KHz clock which pulses high during the LSB
14 RSER O Receive Serial Data. Received NRZ serial data, updated on rising edges
15 RSYNC I/O Receive Sync. An extracted pulse, one RCLK wide, is output at this pin which
16 RLOS/LOTC O Receive Loss of Sync/Loss of Transmit Clock. A dual function output.
17 SYSCLK I System Clock. 1.544 MHz or 2.048 MHz clock. Only used when the elastic
18 RCHBLK O Receive Channel Block. A user programmable output that can be forced
19 ACLKI I Alternate Clock Input. Upon a receive carrier loss, the clock applied at this
AD4 AD5 AD6 AD7
I/O Address/Data Bus. A 8–bit multiplexed address/data bus.
demultiplex the bus.
bits. See Section 13 for timing details.
controlled by RCR2. See Section 13 for timing details.
of each channel. Useful for parallel to serial conversion of channel data. See Section 13 for timing details.
of RCLK or SYSCLK.
identifies either frame (RCR1.6=0) or multiframe boundaries (RCR1.6=1). If the elastic store is enabled via the RCR2.1, then this pin can be enabled to be an input via RCR1.5 at which a frame boundary pulse is applied. See Section 13 for timing details.
If TCR2.0=0, will toggle high when the synchronizer is searching for the E1 frame and multiframe; if TCR2.0=1, will toggle high if the TCLK pin has not toggled for 5 µs.
store functions are enabled via RCR2.1. Should be tied low in applications that do not use the elastic store. If tied high for at least 100 µs, will force all output pins (including the parallel port) to 3–state.
high or low during any of the 32 E1 channels. Useful for blocking clocks to a serial UART or LAPD controller in applications where not all E1 channels are used such as Fractional E1, 384K bps service (H0), 1920K bps (H12), or ISDN–PRI. Also useful for locating individual channels in drop–and–insert applications. See Section 13 for timing details.
pin (normally 2.048 MHz) will be routed to the RCLK pin. If no clock is routed to this pin, then it should be tied to DVSS.
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DS2153Q
PIN DESCRIPTIONTYPESYMBOL
20 BTS I Bus Type Select. Strap high to select Motorola bus timing; strap low to
select Intel bus timing. This pin controls the function of the RD ALE(AS), and WR
(R/W) pins. If BTS=1, then these pins assume the function
(DS),
listed in parenthesis ().
21 22
RTIP
RRING
Receive Tip and Ring. Analog inputs for clock recovery circuitry; connects
to a 1:1 transformer (see Section 12 for details).
23 RVDD Receive Analog Positive Supply. 5.0 volts. Should be tied to DVDD and
TVDD pins. 24 RVSS Receive Signal Ground. 0.0 volts. Should be tied to local ground plane. 25
26
XTAL1 XTAL2
Crystal Connections. A pullable 8.192 MHz crystal must be applied to
these pins. See Section 12 for crystal specifications. 27 INT1 O Receive Alarm Interrupt 1. Flags host controller during alarm conditions
defined in Status Register 1. Active low, open drain output. 28 INT2 O Receive Alarm Interrupt 2. Flags host controller during conditions defined
in Status Register 2. Active low, open drain output. 29 TTIP Transmit Tip. Analog line driver output; connects to a step–up transformer
(see Section 12 for details). 30 TVSS Transmit Signal Ground. 0.0 volts. Should be tied to local ground plane. 31 TVDD Transmit Analog Positive Supply. 5.0 volts. Should be tied to DVDD and
RVDD pins. 32 TRING Transmit Ring. Analog line driver outputs; connects to a step–up trans-
former (see Section 12 for details). 33 TCHBLK O Transmit Channel Block. A user programmable output that can be forced
high or low during any of the 32 E1 channels. Useful for blocking clocks to
a serial UART or LAPD controller in applications where not all E1 channels
are used such as Fractional E1, 384K bps service (H0), 1920K bps (H12),
or ISDN–PRI. Also useful for locating individual channels in drop–and–insert
applications. See Section 13 for timing details. 34 TLCLK O Transmit Link Clock. 4 KHz to 20 KHz demand clock for the TLINK input;
controlled by TCR2. See Section 13 for timing details. 35 TLINK I Transmit Link Data. If enabled, this pin will be sampled on the falling edge
of TCLK to insert the Sa bits See Section 13 for timing details. 36 TSYNC I/O Transmit Sync. A pulse at this pin will establish either frame or multiframe
boundaries for the DS2153Q. Via TCR1.1, the DS2153Q can be pro-
grammed to output either a frame or multiframe pulse at this pin. See Section
13 for timing details. 37 DVDD Digital Positive Supply. 5.0 volts. Should be tied to RVDD and TVDD pins. 38 TCLK I Transmit Clock. 2.048 MHz primary clock. Needed for proper operation of
the parallel control port. 39 TSER I Transmit Serial Data. Transmit NRZ serial data, sampled on the falling edge
of TCLK.
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DS2153Q
PIN DESCRIPTIONTYPESYMBOL
40 TCHCLK O Transmit Channel Clock. 256 KHz clock which pulses high during the LSB
of each channel. Useful for parallel to serial conversion of channel data. See Section 13 for timing details.
41 42 43 44
AD0 AD1 AD2 AD3
I/O Address/Data Bus. A 8–bit multiplexed address/data bus.
DS2153Q REGISTER MAP
ADDRESS R/W REGISTER NAME ADDRESS R/W REGISTER NAME
00 R BPV or Code Violation Count 1 20 R/W Transmit Align Frame 01 R BPV or Code Violation Count 2 21 R/W Transmit Non–Align Frame 02 R CRC4 Count 1/FAS Error Count
1 03 R CRC4 Error Count 2 23 R/W Transmit Channel Blocking 2 04 R E–Bit Count 1/FAS Error Count
2 05 R E–Bit Count 2 25 R/W Transmit Channel Blocking 4 06 R Status 1 26 R/W Transmit Idle 1 07 R Status 2 27 R/W Transmit Idle 2 08 R/W Receive Information 28 R/W Transmit Idle 3 10 R/W Receive Control 1 29 R/W Transmit Idle 4 11 R/W Receive Control 2 2A R/W Transmit Idle Definition 12 R/W Transmit Control 1 2B R/W Receive Channel Blocking 1 13 R/W Transmit Control 2 2C R/W Receive Channel Blocking 2 14 R/W Common Control 1 2D R/W Receive Channel Blocking 3 15 R/W Test 1 2E R/W Receive Channel Blocking 4 16 R/W Interrupt Mask 1 2F R Receive Align Frame 17 R/W Interrupt Mask 2 18 R/W Line Interface Control 19 R/W Test 2 1A R/W Common Control 2 1B R/W Common Control 3 1E R Synchronizer Status 1F R Receive Non–Align Frame
22 R/W Transmit Channel Blocking 1
24 R/W Transmit Channel Blocking 3
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ADDRESS REGISTER NAMER/WADDRESSREGISTER NAMER/W
30 R Receive Signaling 1 40 R/W Transmit Signaling 1 31 R Receive Signaling 2 41 R/W Transmit Signaling 2 32 R Receive Signaling 3 42 R/W Transmit Signaling 3 33 R Receive Signaling 4 43 R/W Transmit Signaling 4 34 R Receive Signaling 5 44 R/W Transmit Signaling 5 35 R Receive Signaling 6 45 R/W Transmit Signaling 6 36 R Receive Signaling 7 46 R/W Transmit Signaling 7 37 R Receive Signaling 8 47 R/W Transmit Signaling 8 38 R Receive Signaling 9 48 R/W Transmit Signaling 9
39 R Receive Signaling 10 49 R/W Transmit Signaling 10 3A R Receive Signaling 1 1 4A R/W Transmit Signaling 1 1 3B R Receive Signaling 12 4B R/W Transmit Signaling 12 3C R Receive Signaling 13 4C R/W Transmit Signaling 13 3D R Receive Signaling 14 4D R/W Transmit Signaling 14 3E R Receive Signaling 15 4E R/W Transmit Signaling 15 3F R Receive Signaling 16 4F R/W Transmit Signaling 16
DS2153Q
Note: the Test Registers 1 and 2 are used only by the factory; these registers must be cleared (set to all zeros) on power–up initialization to insure proper operation.
2.0 PARALLEL PORT
The DS2153Q is controlled via a mutliplexed bidirec­tional address/data bus by an external microcontroller
terminated and the bus returns to a high impedance state as RD
transitions high in Intel timing or as DS tran-
sitions low in Motorola timing. or microprocessor. The DS2153Q can operate with either Intel or Motorola bus timing configurations. If the BTS pin is tied low, Intel timing will be selected; if tied high, Motorola timing will be selected. All Motorola bus signals are listed in parenthesis (). See the timing dia­grams in the AC Electrical Characteristics for more details. The mutliplexed bus on the DS2153Q saves pins because the address information and data informa­tion share the same signal paths. The addresses are presented to the pins in the first portion of the bus cycle and data will be transferred on the pins during second portion of the bus cycle. Addresses must be valid prior to the falling edge of ALE(AS), at which time the DS2153Q latches the address from the AD0 to AD7 pins. Valid write data must be present and held stable during the later portion of the DS WR
pulses. In a read cycle, the DS2153Q outputs a byte of data during the latter portion of the DS or RD
pulses. The read cycle is
3.0 CONTROL AND TEST REGISTERS
The operation of the DS2153Q is configured via a set of seven registers. Typically , the control registers are only accessed when the system is first powered up. Once the DS2153Q has been initialized, the control registers will only need to be accessed when there is a change in the system configuration. There are two Receive Con­trol Register (RCR1 and RCR2), two Transmit Control Registers (TCR1 and TCR2), and three Common Con­trol Registers (CCR1, CCR2 and CCR3). Each of the seven registers are described in this section.
The T est Registers at addresses 15 and 19 hex are used by the factory in testing the DS2153Q. On power–up, the T est Registers should be set to 00 hex in order for the DS2153Q to operate properly.
022697 7/48
DS2153Q
RCR1: RECEIVE CONTROL REGISTER 1 (Address=10 Hex)
(MSB) (LSB)
RSMF RSM RSIO FRC SYNCE RESYNC
SYMBOL POSITION NAME AND DESCRIPTION
RSMF RCR1.7 RSYNC Multiframe Function. Only used if the RSYNC pin is pro-
RSM RCR1.6 RSYNC Mode Select.
RSIO RCR1.5 RSYNC I/O Select.
RCR1.4 Not Assigned. Should be set to zero when written. – RCR1.3 Not Assigned. Should be set to zero when written.
FRC RCR1.2 Frame Resync Criteria.
SYNCE RCR1.1 Sync Enable.
RESYNC RCR1.0 Resync. When toggled from low to high, a resync is initiated. Must be
grammed in the multiframe mode (RCR1.6=1). 0=RSYNC outputs CAS multiframe boundaries 1=RSYNC outputs CRC4 multiframe boundaries
0=frame mode (see the timing in Section 13) 1=multiframe mode (see the timing in Section 13)
0=RSYNC is an output (depends on RCR1.6) 1=RSYNC is an input (only valid if elastic store enabled) (note: this bit must be set to zero when RCR2.1=0)
0=resync if FAS received in error 3 consecutive times 1=resync if FAS or bit 2 of non–F AS is received in error 3 consecutive times
0=auto resync enabled 1=auto resync disabled
cleared and set again for a subsequent resync.
SYNC/RESYNC CRITERIA Table 3–1
FRAME OR
MULTIFRAME
LEVEL
FAS FAS present in frames N and N +
CRC4 Two valid MF alignment words
CAS Valid MF alignment word found
022697 8/48
SYNC CRITERIA RESYNC CRITERIA ITU SPEC.
2, and FAS not present in frame N + 1.
found within 8 ms.
and previous time slot 16 con­tains code other than all zeros.
Three consecutive incorrect FAS received.
Alternate (RCR1.2=1) the above criteria is met or three consecu­tive incorrect bit 2 of non–FAS received.
915 or more CRC4 code words out of 1000 received in error.
Two consecutive MF alignment words received in error.
G.706
4.1.1
4.1.2
G.706
4.2
4.3.2 G.732
5.2
RCR2: RECEIVE CONTROL REGISTER 2 (Address=11 Hex)
(MSB) (LSB)
Sa8S Sa7S Sa6S Sa5S Sa4S RSCLKM RESE
SYMBOL POSITION NAME AND DESCRIPTION
Sa8S RCR2.7 Sa8 Bit Select. Set to one to report the Sa8 bit at the RLINK pin; set to zero
to not report the Sa8 bit.
Sa7S RCR2.6 Sa7 Bit Select. Set to one to report the Sa7 bit at the RLINK pin; set to zero
to not report the Sa7 bit.
Sa6S RCR2.5 Sa6 Bit Select. Set to one to report the Sa6 bit at the RLINK pin; set to zero
to not report the Sa6 bit.
Sa5S RCR2.4 Sa5 Bit Select. Set to one to report the Sa5 bit at the RLINK pin; set to zero
to not report the Sa5 bit.
Sa4S RCR2.3 Sa4 Bit Select. Set to one to report the Sa4 bit at the RLINK pin; set to zero
to not report the Sa4 bit.
RSCLKM RCR2.2 Receive Side SYSCLK Mode Select.
0=if SYSCLK is 1.544 MHz 1=if SYSCLK is 2.048 MHz
RESE RCR2.1 Receive Side Elastic Store Enable.
0=elastic store is bypassed 1=elastic store is enabled
RCR2.0 Not Assigned. Should be set to zero when written.
DS2153Q
TCR1: TRANSMIT CONTROL REGISTER 1 (Address=12 Hex)
(MSB) (LSB)
SYMBOL POSITION NAME AND DESCRIPTION
TCR1.7 Not Assigned. Should be set to zero when written to.
TFPT TCR1.6 Transmit Timeslot 0 Pass Through.
T16S TCR1.5 T ransmit T imeslot 16 Data Select .
TUA1 TCR1.4 Transmit Unframed All Ones.
TSiS TCR1.3 Transmit International Bit Select.
TFPT T16S TUA1 TSiS TSA1 TSM TSIO
0=FAS bits/Sa bits/Remote Alarm sourced internally from the TAF and TNAF registers 1=FAS bits/Sa bits/Remote Alarm sourced from TSER
0=sample timeslot 16 at TSER pin 1=source timeslot 16 from TS1 to TS16 registers
0=transmit data normally 1=transmit an unframed all one’s code at TPOS and TNEG
0=sample Si bits at TSER pin 1=source Si bits from TAF and TNAF registers (in this mode, TCR1.6 must be set to 0)
022697 9/48
DS2153Q
TSA1 TCR1.2 Transmit Signaling All Ones.
0=normal operation 1=force timeslot 16 in every frame to all ones
TSM TCR1.1 TSYNC Mode Select.
0=frame mode (see the timing in Section 13) 1=CAS and CRC4 multiframe mode (see the timing in Section 13)
TSIO TCR1.0 TSYNC I/O Select.
0=TSYNC is an input 1=TSYNC is an output
Note: See Figure 13–9 for more details about how the Transmit Control Registers affect the operation of the DS2153Q.
TCR2: TRANSMIT CONTROL REGISTER 2 (Address=13 Hex)
(MSB) (LSB)
Sa8S Sa7S Sa6S Sa5S Sa4S AEBE P16F
SYMBOL POSITION NAME AND DESCRIPTION
Sa8S TCR2.7 Sa8 Bit Select. Set to one to source the Sa8 bit from the TLINK pin; set to
Sa7S TCR2.6 Sa7 Bit Select. Set to one to source the Sa7 bit from the TLINK pin; set to
Sa6S TCR2.5 Sa6 Bit Select. Set to one to source the Sa6 bit from the TLINK pin; set to
Sa5S TCR2.4 Sa5 Bit Select. Set to one to source the Sa5 bit from the TLINK pin; set to
Sa4S TCR2.3 Sa4 Bit Select. Set to one to source the Sa4 bit from the TLINK pin; set to
TCR2.2 Not Assigned. Should be set to zero when written.
AEBE TCR2.1 Automatic E–Bit Enable.
P16F TCR2.0 Function of Pin 16.
zero to not source the Sa8 bit.
zero to not source the Sa7 bit.
zero to not source the Sa6 bit.
zero to not source the Sa5 bit.
zero to not source the Sa4 bit.
0=E–bits not automatically set in the transmit direction 1=E–bits automatically set in the transmit direction
0=Receive Loss of Sync (RLOS) 1=Loss of Transmit Clock (LOTC)
CCR1: COMMON CONTROL REGISTER 1 (Address=14 Hex)
(MSB) (LSB)
FLB
SYMBOL POSITION NAME AND DESCRIPTION
FLB CCR1.7 Framer Loopback.
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THDB3 TG802 TCRC4 RSM RHDB3 RG802 RCRC4
0=loopback disabled 1=loopback enabled
DS2153Q
THDB3 CCR1.6 Transmit HDB3 Enable.
0=HDB3 disabled 1=HDB3 enabled
TG802 CCR1.5 Transmit G.802 Enable. See Section 13 for details.
0=do not force TCHBLK high during bit 1 of timeslot 26 1=force TCHBLK high during bit 1 of timeslot 26
TCRC4 CCR1.4 Transmit CRC4 Enable.
0=CRC4 disabled 1=CRC4 enabled
RSM CCR1.3 Receive Signaling Mode Select.
0=CAS signaling mode 1=CCS signaling mode
RHDB3 CCR1.2 Receive HDB3 Enable.
0=HDB3 disabled 1=HDB3 enabled
RG802 CCR1.1 Receive G.802 Enable. See Section 13 for details.
0=do not force RCHBLK high during bit 1 of timeslot 26 1=force RCHBLK high during bit 1 of timeslot 26
RCRC4 CCR1.0 Receive CRC4 Enable.
0=CRC4 disabled 1=CRC4 enabled
FRAMER LOOPBACK
When CCR1.7 is set to a one, the DS2153Q will enter a Framer LoopBack (FLB) mode. This loopback is useful in testing and debugging applications. In FLB, the DS2153Q will loop data from the transmit side back to the receive side. When FLB is enabled, the following will occur:
1. data will be transmitted as normal at TTIP and TRING
2. data off the E1 line at RTIP and RRING will be ignored
3. the RCLK output will be replaced with the TCLK input.
CCR2: COMMON CONTROL REGISTER 2 (Address=1A Hex)
(MSB) (LSB)
ECUS
SYMBOL POSITION NAME AND DESCRIPTION
ECUS CCR2.7 Error Counter Update Select.
VCRFS CCR2.6 VCR Function Select.
AAIS CCR2.5 Automatic AIS Generation.
ARA CCR2.4 Automatic Remote Alarm Generation.
VCRFS AAIS ARA RSERC LOTCMC RLB LLB
0=update error counters once a second 1=update error counters every 62.5 ms (500 frames)
0=count BiPolar Violations (BPVs) 1=count Code Violations (CVs)
0=disabled 1=enabled
0=disabled 1=enabled
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DS2153Q
RSERC CCR2.3 RSER Control.
LOTCMC CCR2.2 Loss of Transmit Clock Mux Control. Determines whether the transmit
RLB CCR2.1 Remote Loopback.
LLB CCR2.0 Local Loopback.
REMOTE LOOPBACK
When CCR2.1 is set to a one, the DS2153Q will be forced into Remote LoopBack (RLB). In this loopback, data recovered off of the E1 line from the RTIP and RRING pins will be transmitted back onto the E1 line (with any BPV’s that might have occurred intact) via the TTIP and TRING pins. Data will continue to pass through the receive side of the DS2153Q as it would normally and the data at the TSER pin will be ignored. Data in this loopback will pass through the jitter attenua­tor. Please see Figure 1.1 for more details.
LOCAL LOOPBACK
When CCR2.0 is set to a one, the DS2153Q will be forced into Local LoopBack (LLB). In this loopback, data will continue to be transmitted as normal through
0=allow RSER to output data as received under all conditions 1=force RSER to one under loss of frame alignment conditions
side formatter should switch to the ever present RCLK if the TCLK should fail to transition (see Figure 1.1). 0=do not switch to RCLK if TCLK stops 1=switch to RCLK if TCLK stops
0=loopback disabled 1=loopback enabled
0=loopback disabled 1=loopback enabled
the transmit side of the SCT. Data being received at RTIP and RRING will be replaced with the data being transmitted. Data in this loopback will pass through the jitter attenuator . Please see Figure 1.1 for more details.
AUTOMATIC ALARM GENERATION
When either CCR2.4 or CCR2.5 is set to one, the DS2153Q monitors the receive side to determine if any of the following conditions are present: loss of receive frame synchronization, AIS alarm (all ones) reception, or loss of receive carrier (or signal). If any one (or more) of the above conditions is present, then the DS2151Q will either force an AIS alarm (if CCR2.5=1) or a Remote Alarm (CCR2.4=1) to be transmitted via the TTIP and TRING pins. It is an illegal state to have both CCR2.4 and CCR2.5 set to one at the same time.
CCR3: COMMON CONTROL REGISTER 3 (Address=1B Hex)
(MSB) (LSB)
TESE TCBFS TIRFS ESR LIRST TSCLKM
SYMBOL POSITION NAME AND DESCRIPTION
TESE CCR3.7 Transmit Elastic Store Enable.
TCBFS CCR3.6 Transmit Channel Blocking Registers (TCBR) Function Select.
TIRFS CCR3.5 T ransmit Idle Registers (TIR) Function Select.
ESR CCR3.4 Elastic Stores Reset. Setting this bit from a one to a zero will force the
022697 12/48
0 = elastic store is disabled 1 = elastic store is enabled
0=TCBRs define the operation of the TCHBLK output pin 1=TCBRs define which signaling bits are to be inserted
0=TIRs define in which channels to insert idle code 1=TIRs define in which channels to insert data from RSER
elastic stores to a known depth. Should be toggled after SYSCLK has been
DS2153Q
applied and is stable. Must be set and cleared again for a subsequent reset. Do not leave this bit set high.
LIRST CCR3.3 Line Interface Reset. Setting this bit from a zero to a one will initiate an
internal reset that affects the slicer, AGC, clock recovery state machine, and jitter attenuator . Normally this bit is only toggled on power–up. Must be cleared and set again for a subsequent reset.
CCR3.2 Not Assigned. Should be set to zero when written.
TSCLKM CCR3.1 T ransmit Backplane Clock Select. Must be set like RCR2.2.
0 = 1.544 MHz 1 = 2.048 MHz
CCR3.0 Not Assigned. Should be set to zero when written.
POWER–UP SEQUENCE
On power–up, after the supplies are stable, the DS2153Q should be configured for operation by writing to all of the internal registers (this includes the T est Reg­isters) since the contents of the internal registers cannot be predicted on power–up. Next, the LIRST bit should be toggled from zero to one to reset the line interface cir­cuitry (it will take the DS2153Q about 40 ms to recover from the LIRST bit being toggled). Finally, after the SY­SCLK input is stable, the ESR bit should be toggled from a zero to a one and back to zero (this step can be skipped if the elastic store is not being used).
4.0 STATUS AND INFORMATION REGISTERS
There is a set of four registers that contain information on the current real time status of the DS2153Q, Status Register 1 (SR1), Status Register 2 (SR2), Receive Information Register (RIR), and Synchronizer Status Register (SSR). When a particular event has occurred (or is occurring), the appropriate bit in one of these four registers will be set to a one. All of the bits in these regis­ters operate in a latched fashion (except for the SSR). This means that if an event occurs and a bit is set to a one in any of the registers, it will remain set until the user reads that bit. The bit will be cleared when it is read and it will not be set again until the event has occurred again or if the alarm is still present.
The user will always precede a read of the SR1, SR2, and RIR registers with a write. The byte written to the register will inform the DS2153Q which bits the user wishes to read and have cleared. The user will write a
byte to one of these three registers, with a one in the bit positions he or she wishes to read and a zero in the bit positions he or she does not wish to obtain the latest information on. When a one is written to a bit location, the read register will be updated with current value and it will be cleared. When a zero is written to a bit position, the read register will not be updated and the previous value will be held. A write to the status and information registers will be immediately followed by a read of the same register. The read result should be logically AND’ed with the mask byte that was just written and this value should be written back into the same register to insure that bit does indeed clear. This second write step is necessary because the alarms and events in the sta­tus registers occur asynchronously in respect to their access via the parallel port. This write–read–write scheme allows an external microcontroller or micropro­cessor to individually poll certain bits without disturbing the other bits in the register. This operation is key in con­trolling the DS2153Q with higher–order software lan­guages.
The SSR register operates differently than the other three. It is a read only register and it reports the status of the synchronizer in real time. This register is not latched and it is not necessary to precede a read of this registers with a write.
The SR1 and SR2 registers have the unique ability to initiate a hardware interrupt via the INT1
and INT2 pins respectively. Each of the alarms and events in the SR1 and SR2 can be either masked or unmasked from the interrupt pins via the Interrupt Mask Register 1 (IMR1) and Interrupt Mask Register 2 (IMR2) respectively.
022697 13/48
DS2153Q
RIR: RECEIVE INFORMATION REGISTER (Address=08 Hex)
(MSB) (LSB)
TESF TESE JALT RESF RESE CRCRC FASRC CASRC
SYMBOL POSITION NAME AND DESCRIPTION
TESF RIR.7 Transmit Elastic Store Full. Set when the elastic store fills and a frame is
TESE RIR.6 Transmit Elastic Store Empty . Set when the elastic store empties and a
JALT RIR.5 Jitter Attenuator Limit Trip. Set when the jitter attenuator FIFO reaches to
RESF RIR.4 Elastic Store Full. Set when the elastic store buffer fills and a frame is
RESE RIR.3 Elastic Store Empty. Set when the elastic store buffer empties and a
CRCRC RIR.2 CRC Resync Criteria Met. Set when 915/1000 code words are received in
FASRC RIR.1 FAS Resync Criteria Met. Set when three consecutive FAS words are
CASRC RIR.0 CAS Resync Criteria Met. Set when two consecutive CAS MF alignment
deleted.
frame is repeated.
within 4–bits of it’s limit; useful for debugging jitter attenuation operation.
deleted.
frame is repeated.
error.
received in error.
words are received in error.
SSR: SYNCHRONIZER STATUS REGISTER (Address=1E Hex)
(MSB) (LSB)
CSC5
SYMBOL POSITION NAME AND DESCRIPTION
CSC5 SSR.7 CRC4 Sync Counter Bit 5. MSB of the 6–bit counter. CSC4 SSR.6 CRC4 Sync Counter Bit 4. CSC3 SSR.5 CRC4 Sync Counter Bit 3. CSC2 SSR.4 CRC4 Sync Counter Bit 2. CSC0 SSR.3 CRC4 Sync Counter Bit 0. LSB of the 6–bit counter. The next to LSB bit is
FASSA SSR.2 F AS Sync Active. Set while the synchronizer is searching for alignment at
CASSA SSR.1 CAS MF Sync Active. Set while the synchronizer is searching for the CAS
CRC4SA SSR.0 CRC4 MF Sync Active. Set while the synchronizer is searching for the
022697 14/48
CSC4 CSC3 CSC2 CSC0 FASSA CASSA CRC4SA
not accessible. This bit will toggle each time the CRC4 MF search times out at 8 ms.
the FAS level.
MF alignment word.
CRC4 MF alignment word.
DS2153Q
CRC4 SYNC COUNTER
The CRC4 Sync Counter increments each time the 8 ms CRC4 multiframe search times out. The counter is cleared when the DS2153Q has successfully obtained synchronization at the CRC4 level. The counter can also be cleared by disabling the CRC4 mode
amount of time the DS2153Q has been searching for synchronization at the CRC4 level. Annex B of CCITT G.706 suggests that if synchronization at the CRC4 level cannot be obtained within 400 ms, then the search should be abandoned and proper action taken. The CRC4 Sync Counter will rollover.
(CCR1.0=0). This counter is useful for determining the
SR1: STATUS REGISTER 1 (Address=06 Hex)
(MSB) (LSB)
RSA1
SYMBOL POSITION NAME AND DESCRIPTION
RSA1 SR1.7 Receive Signaling All Ones. Set when the contents of timeslot 16 con-
RDMA SR1.6 Receive Distant MF Alarm. Set when bit 6 of timeslot 16 in frame 0 has
RSA0 SR1.5 Receive Signaling All Zeros. Set when over a full MF, timeslot 16 con-
RSLIP SR1.4 Receive Elastic Store Slip Occurrence. Set when the elastic store has
RUA1 SR1.3 Receive Unframed All Ones. Set when an unframed all ones code is
RRA SR1.2 Receive Remote Alarm. Set when a remote alarm is received at RTIP and
RCL SR1.1 Receive Carrier Loss. Set when 255 consecutive zeros have been
RLOS SR1.0 Receive Loss of Sync. Set when the device is not synchronized to the
RDMA RSA0 RSLIP RUA1 RRA RCL RLOS
tains less than three zeros over 16 consecutive frames. This alarm is not disabled in the CCS signaling mode.
been set for two consecutive multiframes. This alarm is not disabled in the CCS signaling mode.
tains all zeros.
either repeated or deleted a frame of data.
received at RTIP and RRING.
RRING.
detected at RTIP and RRING.
receive E1 stream.
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DS2153Q
ALARM CRITERIA Table 4–1
ALARM SET CRITERIA CLEAR CRITERIA
RSA1
(receive signaling all ones)
RSA0
(receive signaling all zeros)
RDMA
(receive distant
over 16 consecutive frames (one full MF) timeslot 16 contains less than 3 zeros
over 16 consecutive frames (one full MF) timeslot 16 contains all zeros
bit 6 in timeslot 16 of frame 0 set to one for two consecutive MF
over 16 consecutive frames (one full MF) timeslot 16 contains 3 or more zeros
over 16 consecutive frames (one full MF) timeslot 16 contains at least a single one
bit 6 in timeslot 16 of frame 0 set to zero for a two consecutive MF
multiframe alarm)
RUA1
(receive unframed
less than 3 zeros in two frames (512 bits)
more than 2 zeros in two frames (512 bits)
all ones)
RRA
(receive remote
bit 3 of non–align frame set to one for 3 consecutive occasions
bit 3 of non–align frame set to zero for 3 consecutive occasions
alarm)
RCL
(receive carrier
255 consecutive zeros received in 255–bit times, at least 32 ones are
received
loss)
SR2: STATUS REGISTER 2 (Address=07 Hex)
(MSB) (LSB)
RMF RAF TMF SEC TAF LOTC RCMF TSLIP
CCITT SPEC.
G.732
4.2
G.732
5.2
O.162
2.1.5
O.162
1.6.1.2
O.162
2.1.4
G.775
SYMBOL POSITION NAME AND DESCRIPTION
RMF SR2.7 Receive CAS Multiframe. Set every 2 ms (regardless if CAS signaling is
enabled or not) on receive multiframe boundaries. Used to alert the host that signaling data is available.
RAF SR2.6 Receive Align Frame. Set every 250 µs at the beginning of align frames.
Used to alert the host that Si and Sa bits are available in the RAF and RNAF registers.
TMF SR2.5 T ransmit Multiframe. Set every 2 ms (regardless if CRC4 is enabled) on
transmit multiframe boundaries. Used to alert the host that signaling data needs to be updated.
SEC SR2.4 One Second Timer . Set on increments of one second based on RCLK. If
CCR2.7=1, then this bit will be set every 62.5 ms instead of once a second.
TAF SR2.3 Transmit Align Frame. Set every 250 µs at the beginning of align frames.
Used to alert the host that the TAF and TNAF registers need to be updated.
LOTC SR2.2 Loss of T ransmit Clock. Set when the TCLK pin has not transitioned for
one channel time (or 3.9 µs). Will force pin 16 high if enabled via TCR2.0. Based on RCLK.
RCMF SR2.1 Receive CRC4 Multiframe. Set on CRC4 multiframe boundaries; will con-
tinue to be set every 2 ms on an arbitrary boundary if CRC4 is disabled.
TSLIP SR2.0 Transmit Elastic Store Slip. Set when the elastic store has either re-
peated or deleted a frame of data.
022697 16/48
IMR1: INTERRUPT MASK REGISTER 1 (Address=16 Hex)
(MSB) (LSB)
RSA1 RDMA RSA0 RSLIP RUA1 RRA RCL RLOS
SYMBOL POSITION NAME AND DESCRIPTION
RSA1 IMR1.7 Receive Signaling All Ones.
0=interrupt masked 1=interrupt enabled
RDMA IMR1.6 Receive Distant MF Alarm.
0=interrupt masked 1=interrupt enabled
RSA0 IMR1.5 Receive Signaling All Zeros.
0=interrupt masked 1=interrupt enabled
RSLIP IMR1.4 Receive Elastic Store Slip Occurrence.
0=interrupt masked 1=interrupt enabled
RUA1 IMR1.3 Receive Unframed All Ones.
0=interrupt masked 1=interrupt enabled
RRA IMR1.2 Receive Remote Alarm.
0=interrupt masked 1=interrupt enabled
RCL IMR1.1 Receive Carrier Loss.
0=interrupt masked 1=interrupt enabled
RLOS IMR1.0 Receive Loss of Sync.
0=interrupt masked 1=interrupt enabled
DS2153Q
022697 17/48
DS2153Q
IMR2: INTERRUPT MASK REGISTER 2 (Address=17 Hex)
(MSB) (LSB)
RMF RAF TMF SEC TAF LOTC RCMF TSLIP
SYMBOL POSITION NAME AND DESCRIPTION
RMF IMR2.7 Receive CAS Multiframe.
RAF IMR2.6 Receive Align Frame.
TMF IMR2.5 T ransmit Multiframe.
SEC IMR2.4 One Second Timer.
TAF IMR2.3 Transmit Align Frame.
LOTC IMR2.2 Loss Of Transmit Clock.
RCMF IMR2.1 Receive CRC4 Multiframe.
TSLIP IMR2.0 Transmit Side Elastic Store Slip.
5.0 ERROR COUNT REGISTERS
There are a set of four counters in the DS2153Q that record bipolar or code violations, errors in the CRC4 SMF code words, E bits as reported by the far end, and word errors in the FAS. Each of these four counters are automatically updated on either one second boundaries (CCR2.7=0) or every 62.5 ms (CCR2.7=1) as determined by the timer in Status Register 2 (SR2.4). Hence, these regis­ters contain performance data from either the previous second or the previous 62.5 ms. The user can use the interrupt from the timer to determine when to read these registers. The user has a full second (or 62.5 ms) to read the counters before the data is lost.
5.1 BPV or Code Violation Counter
Violation Count Register 1 (VCR1) is the most signifi­cant word and VCR2 is the least significant word of a
0=interrupt masked 1=interrupt enabled
0=interrupt masked 1=interrupt enabled
0=interrupt masked 1=interrupt enabled
0=interrupt masked 1=interrupt enabled
0=interrupt masked 1=interrupt enabled
0=interrupt masked 1=interrupt enabled
0=interrupt masked 1=interrupt enabled
0 = interrupt masked 1 = interrupt enabled
16–bit counter that records either BiPolar Violations (BPVs) or Code Violations (CVs). If CCR2.6=0, then the VCR counts bipolar violations. Bipolar violations are defined as consecutive marks of the same polarity. In this mode, if the HDB3 mode is set for the receive side via CCR1.2, then HDB3 code words are not counted as BPVs. If CCR2.6=1, then the VCR counts code viola­tions as defined in CCITT O.161. Code violations are defined as consecutive bipolar violations of the same polarity . In most applications, the DS2153Q should be programmed to count BPVs when receiving AMI code and to count CVs when receiving HDB3 code. This counter increments at all times and is not disabled by loss of sync conditions. The counter saturates at 65,535 and will not rollover. The bit error rate on a E1 line would have to be greater than 10**–2 before the VCR would saturate.
022697 18/48
VCR1: UPPER BIPOLAR VIOLATION COUNT REGISTER 1 (Address=00 Hex) VCR2: LOWER BIPOLAR VIOLATION COUNT REGISTER 2 (Address=01 Hex)
(MSB) (LSB)
V15
V7 V6 V5 V4 V3 V2 V1 V0
SYMBOL POSITION NAME AND DESCRIPTION
V14 V13 V12 V11 V10 V9 V8
V15 VCR1.7 MSB of the 16–bit bipolar or code violation count
V0 VCR2.0 LSB of the 16–bit bipolar or code violation count
DS2153Q
VCR1 VCR2
5.2 CRC4 Error Counter
CRC4 Count Register 1 (CRCCR1) is the most signifi­cant word and CRCCR2 is the least significant word of a 10–bit counter that records word errors in the Cyclic Redundancy Check 4 (CRC4). Since the maximum
CRC4 count in a one second period is 1000, this counter cannot saturate. The counter is disabled during loss of sync at either the FAS or CRC4 level; it will continue to count if loss of multiframe sync occurs at the CAS level.
CRCCR1: CRC4 COUNT REGISTER 1 (Address=02 Hex) CRCCR2: CRC4 COUNT REGISTER 2 (Address=03 Hex)
(MSB) (LSB)
(note 1)
CRC7 CRC6 CRC5 CRC4 CRC3 CRC2 CRC1 CRC0
SYMBOL POSITION NAME AND DESCRIPTION
(note 1) (note 1) (note 1) (note 1) (note 1) CRC9 CRC8
CRC9 CRCCR1.1 MSB of the 10–bit CRC4 error count CRC0 CRCCR2.0 LSB of the 10–bit CRC4 error count
CRCCR1 CRCCR2
NOTES:
1. The upper six bits of CRCCR1 at address 02 are the most significant bits of the 12–bit FAS error counter.
5.3 E–Bit Counter
E–bit Count Register 1 (EBCR1) is the most significant word and EBCR2 is the least significant word of a 10–bit counter that records Far End Block Errors (FEBE) as reported in the first bit of frames 13 and 15 on E1 lines running with CRC4 multiframe. These count registers
will increment once each time the received E–bit is set to zero. Since the maximum E–bit count in a one second period is 1000, this counter cannot saturate. The counter is disabled during loss of sync at either the FAS or CRC4 level; it will continue to count if loss of multi­frame sync occurs at the CAS level.
022697 19/48
DS2153Q
EBCR1: E–BIT COUNT REGISTER 1 (Address=04 Hex) EBCR2: E–BIT COUNT REGISTER 2 (Address=05 Hex)
(MSB) (LSB)
(note 1)
EB7 EB6 EB5 EB4 EB3 EB2 EB1 EB0
SYMBOL POSITION NAME AND DESCRIPTION
(note 1) (note 1) (note 1) (note 1) (note 1) EB9 EB8
EB9 EBCR1.1 MSB of the 10–bit E–Bit count EB0 EBCR2.0 LSB of the 10–bit E–Bit count
EBCR1 EBCR2
NOTES:
1. The upper six bits of EBCR1 at address 04 are the least significant bits of the 12–bit FAS error counter.
5.4 FAS Bit Error Counter
FAS Count Register 1 (F ASCR1) is the most significant word and FASCR2 is the least significant word of a 12–bit counter that records word errors in the Frame Alignment Signal in timeslot 0. This counter is disabled
during loss of frame synchronization conditions, it is not disabled during loss of synchronization at either the CAS or CRC4 multiframe level. Since the maximum FAS word error count in a one second period is 4000, this counter cannot saturate.
FASCR1: FAS BIT COUNT REGISTER 1 (Address=02 Hex) FASCR2: FAS BIT COUNT REGISTER 2 (Address=04 Hex)
(MSB) (LSB)
FAS11 FAS10 FAS9 FAS8 FAS7 FAS6 (note 2) (note 2)
FAS5 FAS4 FAS3 F AS2 FAS1 FAS0 (note 1) (note 1)
SYMBOL POSITION NAME AND DESCRIPTION
FAS11 FASCR1.7 MSB of the 12–bit FAS error count
FAS0 FASCR2.2 LSB of the 12–bit FAS error count
FASCR1 FASCR2
NOTES:
1. The lower two bits of FASCR1 at address 02 are the most significant bits of the 10–bit CRC4 error counter.
2. The lower two bits of FASCR2 at address 04 are the most significant bits of the 10–bit E–Bit counter.
6.0 Sa DATA LINK CONTROL AND OPERATION
The DS2153Q provides for access to the proposed E1 performance monitor data link in the Sa bit positions. The device allows access to the Sa bits either via a set of two internal registers (RNAF and TNAF) or via two external pins (RLINK and TLINK).
On the receive side, the Sa bits are always reported in the internal RNAF register (see Section 11 for more
details). All five Sa bits are always output at the RLINK pin. See Section 13 for detailed timing. Via RCR2, the user can control the RLCLK pin to pulse during any com­bination of Sa bits. This allows the user to create a clock that can be used to capture the needed Sa bits.
On the transmit side, the individual Sa bits can be either sourced from the internal TNAF register (TCR1.6=0) or from the external TLINK pin. Via TCR2, the DS2153Q can be programmed to source any combination of the
022697 20/48
DS2153Q
additional bits from the TLINK pin. If the user wishes to pass the Sa bits through the DS2153Q without them being altered, then the device should be set up to source all five Sa bits via the TLINK pin and the TLINK pin should be tied to the TSER pin. Please see the timing diagrams and the transmit data flow diagram in Section 13 for examples.
receive stream and inserted into the transmit stream by the DS2153Q. Each of the 30 channels has four signal­ing bits (A/B/C/D) associated with it. The numbers in parenthesis () are the channel associated with a particu­lar signaling bit. The channel numbers have been assigned as described in the ITU documents. For example, channel 1 is associated with timeslot 1 and channel 30 is associated with timeslot 31. There is a set
7.0 SIGNALING OPERATION
The Channel Associated Signaling (CAS) bits embedded in the E1 stream can be extracted from the
of 16 registers for the receive side (RS1 to RS16) and 16 registers on the transmit side (TS1 to TS16). The signaling registers are detailed below.
RS1 TO RS16: RECEIVE SIGNALING REGISTERS (Address=30 to 3F Hex)
(MSB) (LSB)
0 0 0 0 X Y X X
A(1) B(1) C(1) D(1) A(16) B(16) C(16) D(16) A(2) B(2) C(2) D(2) A(17) B(17) C(17) D(17) A(3) B(3) C(3) D(3) A(18) B(18) C(18) D(18) A(4) B(4) C(4) D(4) A(19) B(19) C(19) D(19) A(5) B(5) C(5) D(5) A(20) B(20) C(20) D(20) A(6) B(6) C(6) D(6) A(21) B(21) C(21) D(21) A(7) B(7) C(7) D(7) A(22) B(22) C(22) D(22) A(8) B(8) C(8) D(8) A(23) B(23) C(23) D(23)
A(9) B(9) C(9) D(9) A(24) B(24) C(24) D(24) A(10) B(10) C(10) D(10) A(25) B(25) C(25) D(25) A(11) B(11) C(1 1) D(11) A(26) B(26) C(26) D(26) A(12) B(12) C(12) D(12) A(27) B(27) C(27) D(27) A(13) B(13) C(13) D(13) A(28) B(28) C(28) D(28) A(14) B(14) C(14) D(14) A(29) B(29) C(29) D(29) A(15) B(15) C(15) D(15) A(30) B(30) C(30) D(30)
RS1 (30) RS2 (31) RS3 (32) RS4 (33) RS5 (34) RS6 (35) RS7 (36) RS8 (37) RS9 (38) RS10 (39) RS11 (3A) RS12 (3B) RS13 (3C) RS14 (3D) RS15 (3E) RS16 (3F)
SYMBOL POSITION NAME AND DESCRIPTION
X RS1.0/1/3 Spare Bits Y RS1.2 Remote Alarm Bit (integrated and reported in SR1.6)
A(1) RS2.7 Signaling Bit A for Channel 1
D(30) RS16.0 Signaling Bit D for Channel 30
Each Receive Signaling Register (RS1 to RS16) reports the incoming signaling from two timeslots. The bits in the Receive Signaling Registers are updated on multi­frame boundaries so the user can utilize the Receive
Multiframe Interrupt in the Receive Status Register 2 (SR2.7) to know when to retrieve the signaling bits. The user has a full 2 ms to retrieve the signaling bits before the data is lost. The RS registers are updated under all
022697 21/48
DS2153Q
conditions. Their validity should be qualified by check­ing for synchronization at the CAS level. In CCS signal­ing mode, RS1 to RS16 can also be used to extract
informed when the signaling registers have been loaded with data. The user has 2 ms to retrieve the data before it is lost.
signaling information. Via the SR2.7 bit, the user will be
TS1 TO TS16: TRANSMIT SIGNALING REGISTERS (Address=40 to 4F Hex)
(MSB) (LSB)
0 0 0 0 X Y X X
A(1) B(1) C(1) D(1) A(31) B(16) C(16) D(16) A(2) B(2) C(2) D(2) A(32) B(17) C(17) D(17) A(3) B(3) C(3) D(3) A(33) B(18) C(18) D(18) A(4) B(4) C(4) D(4) A(34) B(19) C(19) D(19) A(5) B(5) C(5) D(5) A(35) B(20) C(20) D(20) A(6) B(6) C(6) D(6) A(36) B(21) C(21) D(21) A(7) B(7) C(7) D(7) A(37) B(22) C(22) D(22) A(8) B(8) C(8) D(8) A(38) B(23) C(23) D(23) A(9) B(9) C(9) D(9) A(39) B(24) C(24) D(24)
A(10) B(10) C(10) D(10) A(40) B(25) C(25) D(25)
A(11) B(11) C(1 1) D(11) A(41) B(26) C(26) D(26) A(12) B(12) C(12) D(12) A(42) B(27) C(27) D(27) A(13) B(13) C(13) D(13) A(43) B(28) C(28) D(28) A(14) B(14) C(14) D(14) A(44) B(29) C(29) D(29) A(15) B(15) C(15) D(15) A(45) B(30) C(30) D(30)
TS1 (40) TS2 (41) TS3 (42) TS4 (43) TS5 (44) TS6 (45) TS7 (46) TS8 (47) TS9 (48) TS10 (49) TS11 (4A) TS12 (4B) TS13 (4C) TS14 (4D) TS15 (4E) TS16 (4F)
SYMBOL POSITION NAME AND DESCRIPTION
X TS1.0/1/3 Spare Bits Y TS1.2 Remote Alarm Bit
A(1) TS2.7 Signaling Bit A for Channel 1
D(30) TS16.0 Signaling Bit D for Channel 30
Each Transmit Signaling Register (TS1 to TS16) con­tains the CAS bits for two timeslots that will be inserted into the outgoing stream if enabled to do so via TCR1.5. On multiframe boundaries, the DS2153Q will load the values present in the Transmit Signaling Register into an outgoing signaling shift register that is internal to the device. The user can utilize the Transmit Multiframe bit in Status Register 2 (SR2.5) to know when to update the signaling bits. The bit will be set every 2 ms and the user has 2 ms to update the TSR’s before the old data will be retransmitted.
022697 22/48
The TS1 register is special because it contains the CAS multiframe alignment word in its upper nibble. The upper nibble must always be set to 0000 or else the ter­minal at the far end will lose multiframe synchronization. If the user wishes to transmit a multiframe alarm to the far end, then the TS1.2 bit should be set to a one. If no alarm is to be transmitted, then the TS1.2 bit should be cleared. The three remaining bits in TS1 are the spare bits. If they are not used, they should be set to one. In CCS signaling mode, TS1 to TS16 can also be used to insert signaling information. Via the SR2.5 bit, the user
DS2153Q
will be informed when the signaling registers need to be loaded with data. The user has 2 ms to load the data before the old data will be retransmitted. Via the CCR3.6 bit, the user has the option to use the Transmit Channel Blocking Registers (TCBRs) to determine on a channel by channel basis, which signaling bits are to be inserted via the TSRs (the corresponding bit in the TCBRs=1) and which are to be sourced from the TSER pin (the corresponding bit in the TCBRs=0). See the
Transmit Data Flow diagram in Section 13 for more details.
8.0 TRANSMIT IDLE REGISTERS
There is a set of five registers in the DS2153Q that can be used to custom tailor the data that is to be transmitted onto the E1 line, on a channel by channel basis. Each of the 32 E1 channels can be forced to have a user defined idle code inserted into them.
TIR1/TIR2/TIR3/TIR4: TRANSMIT IDLE REGISTERS (Address=26 to 29 Hex)
(MSB) (LSB)
CH8 CH16 CH15 CH14 CH13 CH12 CH11 CH10 CH9 CH24 CH23 CH22 CH21 CH20 CH19 CH18 CH17 CH32 CH31 CH30 CH29 CH28 CH27 CH26 CH25
SYMBOL POSITION NAME AND DESCRIPTION
CH32 TIR4.7 Transmit Idle Registers.
CH7 CH6 CH5 CH4 CH3 CH2 CH1
0=do not insert the Idle Code into this channel
CH1 TIR1.0 1=insert the Idle Code into this channel
TIR1 (26) TIR2 (27) TIR3 (28) TIR4 (29)
NOTE:
If CCR3.5=1, then a zero in the TIRs implies that channel data is to be sourced from TSER and a one implies that channel data is to be sourced from the RSER pin.
TIDR: TRANSMIT IDLE DEFINITION REGISTER (Address=2A Hex)
(MSB) (LSB)
TIDR7 TIDR6 TIDR5 TIDR4 TIDR3 TIDR2 TIDR1 TIDR0
SYMBOL POSITION NAME AND DESCRIPTION
TIDR7 TIDR.7 MSB of the Idle Code TIDR0 TIDR.0 LSB of the Idle Code
Each of the bit positions in the Transmit Idle Registers (TIR1/TIR2/TIR3/TIR4) represent a timeslot in the out­going frame. When these bits are set to a one, the corre­sponding channel will transmit the Idle Code contained in the Transmit Idle Definition Register (TIDR). In the TIDR, the MSB is transmitted first. Via the CCR3.5 bit, the user has the option to use the TIRs to determine on a channel by channel basis, if data from the RSER pin should be substituted for data from the TSER pin. In this
mode, if the corresponding bit in the TIRs is set to one, then data will be sourced from the RSER pin. If the cor­responding bit in the TIRs is set to zero, then data for that channel will sourced from the TSER pin. See the Transmit Data Flow diagram in Section 13 for more details.
022697 23/48
DS2153Q
9.0 CLOCK BLOCKING REGISTERS
The Receive Channel Blocking Registers (RCBR1/RCBR2/RCBR3/RCBR4) and the Transmit Channel Blocking Registers (TCBR1/TCBR2/TCBR3/ TCBR4) control the RCHBLK and TCHBLK pins respectively. The RCHBLK and TCHCLK pins are user programmable outputs that can be forced either high or low during individual channels. These outputs can be used to block clocks to a USART or LAPD controller in ISDN–PRI applications. When the appropriate bits are set to a one, the RCHBLK and TCHCLK pins will be held
high during the entire corresponding channel time. See the timing in Section 13 for an example. The TCBRs have alternate mode of use. Via the CCR3.6 bit, the user has the option to use the TCBRs to determine on a channel by channel basis, which signaling bits are to be inserted via the TSRs (the corresponding bit in the TCBRs=1) and which are to be sourced from the TSER pin (the corresponding bit in the TCBR=0). See the Transmit Data Flow diagram in Section 13 for more details.
RCBR1/RCBR2/RCBR3/RCBR4: RECEIVE CHANNEL BLOCKING REGISTERS
(Address=2B to 2E Hex)
(MSB) (LSB)
CH8 CH16 CH15 CH14 CH13 CH12 CH11 CH10 CH9 CH24 CH23 CH22 CH21 CH20 CH19 CH18 CH17 CH32 CH31 CH30 CH29 CH28 CH27 CH26 CH25
SYMBOL POSITION NAME AND DESCRIPTION
CH32 RCBR4.7 Receive Channel Blocking Registers.
CH7 CH6 CH5 CH4 CH3 CH2 CH1
0=force the RCHBLK pin to remain low during this channel time
CH1 RCBR1.0 1=force the RCHBLK pin high during this channel time
RCBR1 (2B) RCBR2 (2C) RCBR3 (2D) RCBR4 (2E)
TCBR1/TCBR2/TCBR3/TCBR4: TRANSMIT CHANNEL BLOCKING REGISTERS
(Address=22 to 25 Hex)
(MSB) (LSB)
CH8 CH16 CH15 CH14 CH13 CH12 CH11 CH10 CH9 CH24 CH23 CH22 CH21 CH20 CH19 CH18 CH17 CH32 CH31 CH30 CH29 CH28 CH27 CH26 CH25
SYMBOL POSITION NAME AND DESCRIPTION
CH32 TCBR4.7 Transmit Channel Blocking Registers.
CH7 CH6 CH5 CH4 CH3 CH2 CH1
0=force the TCHBLK pin to remain low during this channel time
CH1 TCBR1.0 1=force the TCHBLK pin high during this channel time
TCBR1 (22) TCBR2 (23) TCBR3 (24) TCBR4 (25)
NOTE:
If CCR3.6=1, then a zero in the TCBRs implies that signaling data is to be sourced from TSER and a one implies that signaling data for that channel is to be sourced from the Transmit Signaling (TS) registers. See definition below.
022697 24/48
DS2153Q
TCBR1/TCBR2/TCBR3/TCBR4: DEFINITION WHEN CCR3.6 = 1
(MSB) (LSB)
CH20 CH24 CH8 CH23 CH7 CH22 CH6 CH21 CH5 CH28 CH12 CH27 CH11 CH26 CH10 CH25 CH9 CH32 CH16 CH31 CH15 CH30 CH14 CH29 CH13
* = CH1 and CH17 should be set to one to allow the internal TS1 register to create the CAS Multiframe Alignment Word and Spare/Remote Alarm bits.
CH4 CH19 CH3 CH18 CH2 CH17* CH1*
TCBR1 TCBR2 TCBR3 TCBR4
10.0 ELASTIC STORE OPERATION
The DS2153Q has an onboard two frame (512 bits) elastic store. This elastic store can be enabled via RCR2.1. If the elastic store is enabled (RCR2.1=1), then the user must provide either a 1.544 MHz (RCR2.2=0) or 2.048 MHz (RCR2.2=1) clock at the SYSCLK pin. If the elastic store is enabled, then the user has the option of either providing a frame sync at the RSYNC pin (RCR1.5=1) or having the RSYNC pin provide a pulse on frame or multiframe boundaries (RCR1.5=0). If the user wishes to obtain pulses at the frame boundary , then RCR1.6 must be set to zero and if the user wishes to have pulses occur at the multiframe boundary , then RCR1.6 must be set to one. If the user selects to apply a 1.544 MHz clock to the SYSCLK pin, then every fourth channel will be deleted and the F–bit position inserted (forced to one). Hence channels 1, 5, 9, 13, 17, 21, 25, and 29 (timeslots 0, 4, 8, 12, 16, 20, 24, and 28) will be deleted. Also, in 1.544 MHz applications, the RCHBLK output will not be active in channels 25 through 32 (or in other words, RCBR4 is not active). See Section 13 for more details. If the 512–bit elastic buffer either fills or empties, a controlled slip will occur . If the buffer empties, then a full frame of data (256 bits) will be repeated at RSER and the SR1.4 and RIR.3 bits will be set to a one. If the buffer fills, then a full frame of data will be deleted and the SR1.4 and RIR.4 bits will be set to a one.
11.0 ADDITIONAL (Sa) AND INTERNATIONAL (Si) BIT OPERATION
The DS2153Q provides for access to both the Addi­tional (Sa) and International (Si) bits. On the receive side, the RAF and RNAF registers will always report the data as it received in the Additional and International bit locations. The RAF and RNAF registers are updated with the setting of the Receive Align Frame bit in Status Register 2 (SR2.6). The host can use the SR2.6 bit to know when to read the RAF and RNAF registers. It has 250 µs to retrieve the data before it is lost.
On the transmit side, data is sampled from the TAF and TNAF registers with the setting of the Transmit Align Frame bit in Status Register 2 (SR2.3). The host can use the SR2.3 bit to know when to update the T AF and TNAF registers. It has 250 µs to update the data or else the old data will be retransmitted. Data in the Si bit posi­tion will be overwritten if either the DS2153Q is pro­grammed: (1) to source the Si bits from the TSER pin, (2) in the CRC4 mode, or (3) have automatic E–bit inser­tion enabled. Data in the Sa bit position will be overwrit­ten if any of the TCR2.3 to TCR2.7 bits are set to one. Please see the register descriptions for TCR1 and TCR2 and the Transmit Data Flow diagram in Section 13 for more details.
022697 25/48
DS2153Q
RAF: RECEIVE ALIGN FRAME REGISTER (Address=2F Hex)
(MSB) (LSB)
Si 0 0 1 1 0 1 1
SYMBOL POSITION NAME AND DESCRIPTION
Si RAF.7 International Bit.
0 RAF .6 Frame Alignment Signal Bit. 0 RAF .5 Frame Alignment Signal Bit. 1 RAF .4 Frame Alignment Signal Bit. 1 RAF .3 Frame Alignment Signal Bit. 0 RAF .2 Frame Alignment Signal Bit. 1 RAF .1 Frame Alignment Signal Bit. 1 RAF .0 Frame Alignment Signal Bit.
RNAF: RECEIVE NON–ALIGN FRAME REGISTER (Address=1F Hex)
(MSB) (LSB)
Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
SYMBOL POSITION NAME AND DESCRIPTION
Si RNAF.7 International Bit.
1 RNAF.6 Frame Non–Alignment Signal Bit.
A RNAF.5 Remote Alarm. Sa4 RNAF.4 Additional Bit 4. Sa5 RNAF.3 Additional Bit 5. Sa6 RNAF.2 Additional Bit 6. Sa7 RNAF.1 Additional Bit 7. Sa8 RNAF.0 Additional Bit 8.
TAF: TRANSMIT ALIGN FRAME REGISTER (Address=20 Hex)
(MSB) (LSB)
Si
SYMBOL POSITION NAME AND DESCRIPTION
Si TAF.7 International Bit.
0 T AF.6 Frame Alignment Signal Bit.
0 T AF.5 Frame Alignment Signal Bit.
1 T AF.4 Frame Alignment Signal Bit.
022697 26/48
0 0 1 1 0 1 1
1 T AF.3 Frame Alignment Signal Bit. 0 T AF.2 Frame Alignment Signal Bit. 1 T AF.1 Frame Alignment Signal Bit. 1 T AF.0 Frame Alignment Signal Bit.
TNAF: TRANSMIT NON–ALIGN FRAME REGISTER (Address=21 Hex)
(MSB) (LSB)
Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
SYMBOL POSITION NAME AND DESCRIPTION
Si TNAF.7 International Bit.
1 TNAF.6 Frame Non–Alignment Signal Bit.
A TNAF.5 Remote Alarm. Sa4 TNAF.4 Additional Bit 4. Sa5 TNAF.3 Additional Bit 5. Sa6 TNAF.2 Additional Bit 6.
Sa7 TNAF.1 Additional Bit 7.
Sa8 TNAF.0 Additional Bit 8.
DS2153Q
12.0 LINE INTERFACE FUNCTIONS
The line interface function in the DS2153Q contains three sections; (1) the receiver which handles clock and
and drives the E1 line, and (3) the jitter attenuator . Each of the these three sections is controlled by the Line Inter­face Control Register (LICR) which is described below.
data recovery, (2) the transmitter which waveshapes
LICR: LINE INTERFACE CONTROL REGISTER (Address=18 Hex)
(MSB) (LSB)
L2 L1 L0 EGL JAS JABDS DJA TPD
SYMBOL POSITION NAME AND DESCRIPTION
LB2 LICR.7 Line Build Out Bit 2. Transmit waveshape setting; see Table 12.2. LB1 LICR.6 Line Build Out Bit 1. Transmit waveshape setting; see Table 12.2. LB0 LICR.5 Line Build Out Bit 0. Transmit waveshape setting; see Table 12.2.
EGL LICR.4 Receive Equalizer Gain Limit.
JAS LICR.3 Jitter Attenuator Select.
JABDS LICR.2 Jitter Attenuator Buffer Depth Select .
0 = –12 dB 1 = –30 dB
0=place the jitter attenuator on the receive side 1=place the jitter attenuator on the transmit side
0=128 bits 1=32 bits (use for delay sensitive applications)
LICR
022697 27/48
DS2153Q
DJA LICR.1 Disable Jitter Attenuator.
0=jitter attenuator enabled 1=jitter attenuator disabled
TPD LICR.0 Transmit Power Down.
0=normal transmitter operation 1=powers down the transmitter and 3–states the TTIP and TRING pins
12.1 Receive Clock and Data Recovery
The DS2153Q contains a digital clock recovery system. See the DS2153Q Block Diagram in Section 1 and Fig­ure 12.1 for more details. The DS2153Q couples to the receive E1 shielded twisted pair or COAX via a 1:1 transformer. See T able 12.3 for transformer details. The DS2153Q automatically adjusts to the E1 signal being received at the RTIP and RRING pins and can handle E1 twisted pair cables of 0.6 mm (22 AWG) from 0 to 1.5 KM in length. The crystal attached at the XTAL1 and XTAL2 pins is multiplied by four via an internal PLL and fed to the clock recovery system. The clock recovery system uses both edges of the clock from the PLL circuit to form a 32 times oversampler which is used to recover the clock and data. This oversampling technique offers outstanding jitter tolerance (see Figure 12.2).
Normally, the clock that is output at the RCLK pin is the recovered clock from the E1 AMI/HDB3 waveform pres-
SOURCE OF RCLK UPON RCL Table 12–1
ACLKI PRESENT? RECEIVE SIDE JITTER
ATTENUATOR
yes ACLKI via the jitter attenuator ACLKI
no centered crystal TCLK via the jitter attenuator
ented at the RTIP and RRING inputs. When no AMI sig­nal is present at RTIP and RRING, a Receive Carrier Loss (RCL) condition will occur and the RCLK can be sourced from either the ACLKI pin or from the crystal attached to the XT AL1 and XTAL2 pins. The DS2153Q will sense the ACLKI pin to determine if a clock is pres­ent. If no clock is applied to the ACLKI pin, then it should be tied to RVSS to prevent the device from falsely sens­ing a clock. See Table 12.1. If the jitter attenuator is either placed in the transmit path or is disabled, the RCLK output can exhibit short high cycles of the clock. This is due to the highly oversampled digital clock recov­ery circuitry. If the jitter attenuator is placed in the receive path (as is the case in most applications), the jit­ter attenuator restores the RCLK to being close to 50% duty cycle. Please see the Receive AC Timing Charac­teristics in Section 14 for more details.
TRANSMIT SIDE JITTER
ATTENUATOR
12.2 Transmit Waveshaping and Line Driving
The DS2153Q uses a set of laser–trimmed delay lines along with a precision Digital–to–Analog Converter (DAC) to create the waveforms that are transmitted onto the E1 line. The waveforms created by the DS2153Q meet the ITU specifications. See Figure 12.3. The user
022697 28/48
will select which waveform is to be generated by prop­erly programming the L2/L1/L0 bits in the Line Interface Control Register (LICR). The DS2153Q can set set up in a number of various configurations depending on the application. See Table 12.2 and Figure 12.1.
LINE BUILD OUT SELECT IN LICR Table 12–2
L2 L1 L0 APPLICATION TRANSFORMER RETURN LOSS Rt
0 0 0 75 ohm normal 1:1.15 step–up NM 0 ohms 0 0 1 120 ohm normal 1:1.15 step–up NM 0 ohms 0 1 0 75 ohm normal
with protection resistors
0 1 1 120 ohm normal
with protection resistors
1 0 0 75 ohm with high
return loss
1 1 0 75 ohm with high
return loss
1 0 0 120 ohm with
high return loss
NM=Not Meaningful
1:1.15 step–up NM 8.2 ohms
1:1.15 step–up NM 8.2 ohms
1:1.15 step–up 21 dB 27 ohms
1:1.36 step–up 21 dB 18 ohms
1:1.36 step–up 21 dB 27 ohms
DS2153Q
Due to the nature of the design of the transmitter in the DS2153Q, very little jitter (less then 0.00 5UIpp broad­band from 10 Hz to 100 KHz) is added to the jitter pres­ent on TCLK. Also, the waveforms that they create are independent of the duty cycle of TCLK. The transmitter
twisted pair or COAX via a 1:1.15 or 1:1.36 step up transformer as shown in Figure 12.1. In order for the devices to create the proper wavefroms, this trans­former used must meet the specifications listed in Table 12.3.
in the DS2153Q couples to the E1 transmit shielded
TRANSFORMER SPECIFICATIONS Table 12–3
SPECIFICATION RECOMMENDED VALUE
Turns Ratio 1:1 (receive) and 1:1.15 or 1:1.36 (transmit) ±5% Primary Inductance 600 µH minimum Leakage Inductance 1.0 µH maximum Interwinding Capacitance 60 pF maximum DC Resistance 1.2 ohms maximum
12.3 Jitter Attenuator
The DS2153Q contains an onboard jitter attenuator that can be set to a depth of either 32 or 128 bits via the JABDS bit in the Line Interface Control Register (LICR). The 128–bit mode is used in applications where large excursions of wander are expected. The 32–bit mode is used in delay sensitive applications. The characteris­tics of the attenuation are shown in Figure 12.4. The jit­ter attenuator can be placed in either the receive path or the transmit path by appropriately setting or clearing the JAS bit in the LICR. Also, the jitter attenuator can be dis­abled (in effect, removed) by setting the DJA bit in the
LICR. In order for the jitter attenuator to operate prop­erly, a crystal with the specifications listed in Table 12.4 below must be connected to the XTAL1 and XT AL2 pins.
The jitter attenuator divides the clock provided by the
8.192 MHz crystal at the XTAL1 and XTAL2 pins by to create an output clock that contains very little jitter. Onboard circuitry will pull the crystal (by switching in or out load capacitance) to keep it long term averaged to the same frequency as the incoming E1 signal. If the incoming jitter exceeds either 120 UIpp (buffer depth is 128–bits) or 28 UIpp (buffer depth is 32–bits), then the
022697 29/48
DS2153Q
DS2153Q will divide the attached crystal by either 3.5 or
4.5 instead of the normal 4 to keep the buffer from over-
also sets the Jitter Attenuator Limit Trip (JAL T) bit in the Receive Information Register (RIR.5).
flowing. When the device divides by either 3.5 or 4.5, it
CRYSTAL SELECTION GUIDELINES Table 12–4
PARAMETER SPECIFICATION
Parallel Resonant Frequency 8.192 MHz Mode Fundamental Load Capacitance 18 pF to 20 pF (18.5 pF nominal) Tolerance ±50 ppm Pullability CL=10 pF, delta frequency=+175 to +250 ppm
CL=45 pF, delta frequency=–175 to –250 ppm Effective Series Resistance 30 ohms maximum Crystal Cut AT
DS2153Q EXTERNAL ANALOG CONNECTIONS Figure 12–1
+5V
0.1 µF
0.1 µF
E1 TRANSMIT
PAIR
1.15:1
(OR 1.36:1)
(NON–POLARIZED)
Rt
Rt
0.47 µF
TTIP
TRING
DS2153Q
DVDD
DVSS
RVDD
RVSS
0.01 µF
+
68 µF
E1 RECEIVE
LINE
1:1
Rr Rr
0.1 µF
RTIP
RRING
TVDD
TVSS
XTAL1
XTAL2
0.1 µF
8.192 MHz
NOTES:
1. All resistor values are ±1%.
2. The Rt resistors are used to increase the transmitter return loss or to protect the device from over–voltage.
3. The Rr resistors are used to terminate the receive E1 line.
4. For 75 ohm termination, Rr=37.5 ohms/for 120 ohm termination Rr=60 ohms.
5. See the separate Application Note for details on how to construct a protected interface.
022697 30/48
DS2153Q JITTER TOLERANCE Figure 12–2
1K
100
40
10
DS2153Q
TOLERANCE
DS2153Q
UNIT INTERVALS (Ulpp)
1
0.1
MINIMUM TOLERANCE
20 2.4K 18K
10 100 1K 10K 100K1
1.5
LEVEL AS PER
ITU G.823
FREQUENCY (Hz)
DS2153Q TRANSMIT WAVEFORM TEMPLATE Figure 12–3
1.2
1.1
1.0
0.9
0.8
0.7
0.6
0.5
0.4
SCALED AMPLITUDE
0.3
0.2
0.1
(in 75 ohm systems, 1.0 on the scale=2.37Vpeak
in 120 ohm systems, 1.0 on the scale=3.00Vpeak)
0
–0.1
–0.2
194 ns
219 ns
0.2
269 ns
G.703
TEMPLATE
–250 –200 –150 –100 –50 0 50 100 150 200 250
TIME (ns)
022697 31/48
DS2153Q
DS2153Q JITTER ATTENUATION Figure 12–4
0 dB
ITU G.7XX
PROHIBITED AREA
–20 dB
–40 dB
JITTER ATTENUA TION (dB)
–60 dB
1 10 100 1K 10K 100K
FREQUENCY (Hz)
13.0 TIMING DIAGRAMS/SYNCHRONIZATION FLOWCHART/TRANSMIT DATA FLOW DIAGRAM
RECEIVE SIDE TIMING Figure 13–1
FRAME#
RSYNC
RSYNC
RLCLK
RLINK
1
2
3
4
15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1612345614
NOTES:
1. RSYNC in the frame mode (RCR1.6=0).
2. RSYNC in the multiframe mode (RCR1.6=1).
3. RLCLK is programmed to output just the Sa4 bit.
4. RLINK will always output all five Sa bits as well as the rest of the receive data stream.
5. This diagram assumes the CAS MF begins with the FAS word.
022697 32/48
RECEIVE SIDE BOUNDARY TIMING (WITH ELASTIC STORES DISABLED) Figure 13–2
RCLK
DS2153Q
RSER
RSYNC
RCHCLK
RCHBLK
RLINK
RLCLK
RLCLK
RLCLK
1
2
3
4
CHANNEL 32 CHANNEL 1 CHANNEL 2
LSBMSB MSB
Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
NOTES:
1. RCHBLK is programmed to block channel 2.
2. RLINK is programmed to output the Sa4 bits.
3. RLINK is programmed to output the SA4 and SA8 bits.
4. RLINK is programmed to output the Sa5 and Sa7 bits.
5. Shown is a non–align frame boundary.
Sa4 Sa5 Sa6 Sa7 Sa8
022697 33/48
DS2153Q
1.544 MHz BOUNDARY TIMING WITH ELASTIC STORE(S) ENABLED Figure 13–3
SYSCLK
1
RSER TSER
RSYNC
RSYNC
RCHCLK
RCHBLK
,
2
3
4
LSB MSB LSB MSBF
CHANNEL 24/32 CHANNEL 1/2CHANNEL 23/31
NOTES:
1. Data from the E1 channels 1, 5, 9, 13, 17, 21, 25, and 29 is dropped (channel 2 from the E1 link is mapped to channel 1 of the T1 link, etc.) and the F–bit position is added (forced to one).
2. RSYNC is in the output mode (RCR1.5=0).
3. RSYNC is in the input mode (RCR1.5=1).
4. RCHBLK is programmed to block channel 24.
2.048 MHz BOUNDARY TIMING WITH ELASTIC STORE(S) ENABLED Figure 13–4
SYSCLK
RSER, TSER
RSYNC
RSYNC
RCHCLK
RCHBLK
LSB MSB LSB
1
2
3
CHANNEL 32 CHANNEL 1CHANNEL 31
NOTES:
1. RSYNC is in the output mode (RCR1.5=0).
2. RSYNC is in the input mode (RCR1.5=1).
3. RCHBLK is programmed to block channel 1.
022697 34/48
TRANSMIT SIDE TIMING Figure 13–5
DS2153Q
FRAME#
TSYNC
TSYNC
3
TCLK
TLINK
1
2
3
15 16 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
1612345614
NOTES:
1. TSYNC in the frame mode (TCR1.1=0).
2. TSYNC in the multiframe mode (TCR1.1=1).
3. TLINK is programmed to source only the Sa4 bit.
4. This diagram assumbes both the CAS MF and the CRC4 begin with the align frame.
022697 35/48
DS2153Q
TRANSMIT SIDE BOUNDARY TIMING Figure 13–6
TCLK
TSER
TSYNC
TSYNC
TCHCLK
TCHBLK
TLCLK
1
2
3
4
LSB Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8 MSB MSBLSB
CHANNEL 2CHANNEL 1
TLINK
TLCLK
TLINK
4
5
5
Don’t Care
Don’t Care
Don’t CareDon’t Care
NOTES:
1. TSYNC is in the input mode (TCR1.0=0).
2. TSYNC is in the output mode (TCR1.0=1).
3. TCHBLK is programmed to block channel 2.
4. TLINK is programmed to source the Sa4 bits.
5. TLINK is programmed to source the Sa7 and Sa8 bits.
6. Shown is a non–align frame boundary.
7. See Figures 13.3 and 13.4 for details on timing with the transmit side elastic store enabled.
022697 36/48
DS2153Q
G.802 TIMING Figure 13–7
TIMESLOT# 30 31 0 1 2 3 4 5 6 7 8 9 10 1 1 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 0 1 2 3 4
RSYNC/ TSYNC
RCHCLK/ TCHCLK
RCHBLK/
1
TCHBLK
DETAIL
RCLK/TCLK
TIMESLOT 25 TIMESLOT 26
RSER/TSER
RCHCLK/TCHCLK
RCHBLK/TCHCLK
LSB MSB
NOTE:
1. RCHBLK or TCHBLK is programmed to pulse high during timeslots 1 to 15, 17 to 25, and during bit 1 of time­slot 26.
022697 37/48
DS2153Q
DS2153Q SYNCHRONIZATION FLOWCHART Figure 13–8
POWER UP
RLOS=1
RLOS=1
RESYNC IF
RCR1.1=0
INCREMENT CRC4
SYNC COUNTER;
CRC4SA=0
SET FASRC
(RIR.1)
CRC4 RESYNC CRITERIA MET
(RIR.2)
CAS RESYNC
CRITERIA MET;
SET CASRC
(RIR.0)
8 MS TIME OUT
FAS RESYNC
CRITERIA MET
CHECK FOR >=915
OUT OF 1000 CRC
WORD ERRORS
CHECK FOR CAS
MF WORD ERROR
CRC4 MULTIFRAME
SEARCH (IF ENABLED
VIA CCR.0) CRC4SA=1
CRC4 SYNC CRITERIA
MET; CRC4SA=0;
RESET CRC4 SYNC
COUNTER
CHECK FOR FAS
FRAMING ERROR
(DEPENDS ON
RCR1.2)
IF CRC4 IS ON
(CCR1.0=1)
IF CAS IS ON
(CCR1.3=0)
FAS SYNC
CRITERIA MET
FASSA=0
SYNC DECLARED
RLOS=0
CAS MULTIFRAME
SEARCH (IF ENABLED
VIA CCR1.3)
CASSA=1
CAS SYNC
CRITERIA MET
CASSA=0
022697 38/48
DS2153Q TRANSMIT DATA FLOW Figure 13–9
DS2153Q
TCBR1/2/3/4
CCR3.6
TAF
TNAF
0
TIMESLOT 0
PASS–THROUGH
(TCR1.6)
1
Si BIT INSERTION
CONTROL
(TCR1.3)
CRC4 MULTIFRAME ALIGNMENT WORD
GENERATION (CCR1.4)
TCR1.5
KEY
= REGISTER
= DEVICE PIN
= SELECTOR
TSER
1
0
0
E–BIT GENERATION
(TCR2.1)
Sa BIT INSERTION CONTROL (TCR2.3
RECEIVE SIDE
CRC4 ERROR
DETECTOR
1
0
THRU TCR2.7)
AUTO REMOTE
ALARM GENERATION
(CCR2.4)
IDLE CODE/CHANNEL INSERTION CONTROL
TLINK
1
0
1
VIA TIR1/2/3/4
0 SIGNALING BIT
INSERTION CONTROL
TIDR
01
TIR FUNCTION SELECT
TS1 TO TS16
TRANSMIT SIGNALLING
1
0
CRC4 ENABLE
(CCR1.4)
0
TRANSMIT UNFRAMED
ALL ONES (TCR1.4) OR
AUTO AIS (CCR2.5)
RSER
(note 1)
(CCR3.5)
0
ALL ONES
(TCR1.2)
CODE WORD
GENERATION
1
GENERATION
1
AIS
GENERATION
1
AIS
NOTE:
1. TCLK must be tied to RCLK (or SYSCLK if the elastic store is enabled) and TSYNC must be tied to RSYNC for data to be properly sourced from RSER.
TTIP,
TRING
022697 39/48
DS2153Q
ABSOLUTE MAXIMUM RATINGS*
Voltage on Any Pin Relative to Ground –1.0V to +7.0V Operating Temperature 0°C to 70°C Storage Temperature –55°C to +125°C Soldering Temperature 260°C for 10 seconds
* This is a stress rating only and functional operation of the device at these or any other conditions above those
indicated in the operation sections of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability.
(–40°C to +85°C for DS2153QN)
RECOMMENDED DC OPERATION CONDITIONS (0°C to 70°C)
(–40°C to +85°C for DS2153QN)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Logic 1 V Logic 0 V Supply for DS2153Q V Supply for DS2153QN V
DD DD
IH IL
2.0 V
–0.3 +0.8 V
4.75 5.25 V 1
4.80 5.25 V 1
+0.3 V
DD
CAPACITANCE (tA=25°C)
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Input Capacitance C Output Capacitance C
IN
OUT
5 pF 7 pF
DC CHARACTERISTICS (0°C to 70°C; VDD=5V + 5%)
(–40°C to +85°C; V
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Supply Current @ 5V I Input Leakage I Output Leakage I Output Current (2.4V) I Output Current (0.4V) I
DD
LO
OH
OL
IL
–1.0 +1.0 µA 3
–1.0 mA
+4.0 mA
60 mA 2
=5V +5%/–4% for DS2153QN)
DD
1.0 µA 4
NOTES:
1. Applies to RVDD, TVDD, and DVDD.
2. TCLK=2.048 MHz.
3. 0.0V < V
4. Applies to INT1
022697 40/48
< VDD.
IN
and INT2 when 3–stated.
DS2153Q
AC CHARACTERISTICS – PARALLEL PORT (0°C to 70°C; VDD=5V + 5%)
(–40°C to +85°C; V
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
Cycle Time t
CYC
Pulse Width, DS Low or RD High PW Pulse Width, DS High or RD Low PW Input Rise/Fall Times tR, t R/W Hold Time t R/W Setup Time Before DS High t CS Setup Time Before DS, WR or
active
RD CS Hold Time t Read Data Hold Time t Write Data Hold Time t Muxed Address Valid to AS or
ALE fall Muxed Address Hold Time t Delay Time DS, WR or RD to AS
or ALE Rise
RWH RWS
t
CS
CH DHR DHW
t
ASL
AHL
t
ASD
Pulse Width AS or ALE High PW Delay Time, AS or ALE to DS,
or RD
WR Output Data Delay Time from DS
or RD Data Setup Time t
t
ASED
t
DDR
DSW
EL EH
F
ASH
250 ns 150 ns 100 ns
10 ns 50 ns 20 ns
0 ns
10 50 ns
0 ns
20 ns
10 ns 25 ns
40 ns 20 ns
20 100 ns
80 ns
=5V +5%/–4% for DS2153QN)
DD
30 ns
022697 41/48
DS2153Q
INTEL READ BUS AC TIMING Figure 14–1
PW
ALE
t
ASD
ASH
WR
t
ASD
PW
RD
EL
CS
t
ASL
AD0-AD7
INTEL WRITE BUS AC TIMING Figure 14–2
PW
ALE
t
ASD
ASH
t
t
AHL
t
ASED
CS
t
t
CYC
CYC
t
DDR
PW
EH
t
CH
t
DHR
RD
WR
CS
AD0-AD7
022697 42/48
t
ASD
t
ASL
PW
t
ASED
PW
EL
t
CS
t
AHL
EH
t
CH
t
DHW
t
DSW
MOTOROLA BUS AC TIMING Figure 14–3
PW
ASH
AS
DS
R/W
t
ASD
PW
EL
t
ASED
t
RWS
t
CYC
PW
DS2153Q
EH
t
RWH
AD0-AD7
(READ)
CS
AD0-AD7
(WRITE)
t
ASL
t
ASL
t
t
AHL
AHL
t
DDR
t
CS
t
DSW
t
DHR
t
CH
t
DHW
022697 43/48
DS2153Q
AC CHARACTERISTICS – RECEIVE SIDE (0°C to 70°C; VDD=5V ± 5%)
(–40°C to +85°C; V
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
ALCKI/RCLK Period t RCLK Pulse Width t
RCLK Pulse Width t
CP CH
t
CH
t
SYSCLK Period t
t
SYSCLK Pulse Width t
RSYNC Set Up to SYSCLK Fal­ling
RSYNC Pulse Width t
t
SH
t
SU
PW
SYSCLK Rise/Fall Times tR, t Delay RCLK or SYSCLK to RSER
Valid Delay RCLK or SYSCLK to
t
DD
t
RCHCLK Delay RCLK or SYSCLK to
t
RCHBLK Delay RCLK or SYSCLK to
t
RSYNC Delay RCLK to RLCLK t Delay RCLK to RLINK Valid t
CL
CL SP
SP
SL
D1
D2
D3
D4 D5
180 180
90
200
50 50
25 tSH–5 ns
50 ns
F
488 ns 244
244 244
244 648
488
=5V +5%/–4% for DS2153QN)
DD
ns ns
ns ns
ns ns
ns
25 ns 70 ns
50 ns
50 ns
50 ns
50 ns 50 ns
1
2
3 4
NOTES:
1. Jitter attenuator enabled in the receive side path.
2. Jitter attenuator disabled or enabled in the transmit path.
3. SYSCLK=1.544 MHz.
4. SYSCLK=2.048 MHz.
022697 44/48
RECEIVE SIDE AC TIMING Figure 14–4
RCLK
SYSCLK
RSER
RCHCLK
RCHBLK
RSYNC
RSYNC
t
R
1
2
t
F
t
DD
t
D1
t
D3
t
SU
MSB OF
CHANNEL 1
t
D2
DS2153Q
t
CP
t
CL
t
SL
t
PW
t
CH
t
SH
t
SP
t
D4
3
RLCLK
t
D5
3
RLINK
NOTES:
1. RSYNC is in the output mode (RCR1.5=0).
2. RSYNC is in the input mode (RCR1.5=1).
3. RLCLK and RLINK only have a timing relationship to RCLK; no timing relationship between RLCLK/RLINK and RSYNC is implied.
4. RCLK can exhibit a short high time if the jitter attenuator is either disabled or in the transmit path.
022697 45/48
DS2153Q
AC CHARACTERISTICS – TRANSMIT SIDE (0°C to 70°C; VDD=5V + 5%)
(–40°C to +85°C; V
PARAMETER SYMBOL MIN TYP MAX UNITS NOTES
TCLK Period t TCLK Pulse Width t
TSER, TLINK Set Up to TCLK Falling
TSER, TLINK Hold from TCLK Falling
TSYNC Setup to TCLK Falling t TSYNC Pulse Width t
t t
t
CH
SU
HD
HD PW
TCLK Rise/Fall Times tR, t Delay TCLK to TCHCLK t Delay TCLK to TCHBLK t Delay TCLK to TSYNC t Delay TCLK to TLCLK t
CL
D1 D2 D3 D4
P
75 75
25 ns 1
25 ns 1
25 tCH–5 ns 25 ns
F
488 ns
=5V +5%/–4% for DS2153QN)
DD
ns ns
25 ns 50 ns 50 ns 50 ns 50 ns
NOTES:
1. If the transmit side elastic store is enabled,then TSER is sampled on the falling edge of SYSCLK and the parameters tSU and tHD still apply.
022697 46/48
DS2153Q
TRANSMIT SIDE AC TIMING Figure 14–5
t
F
t
D1
t
D3
t
D4
t
TCLK
4
TSER
TCHCLK
TCHBLK
TSYNC
TSYNC
TLCLK
TLINK
t
R
1
2
3
3
t
P
t
CL
t
CH
MSBLSB
t
HD
t
SU
t
D2
t
t
SU
SU
PW
t
HD
NOTES:
1. TSYNC is in the output mode (TCR1.0=1).
2. TSYNC is in the input mode (TCR1.0=0).
3. No timing relationship between TSYNC and TLCLK/TLINK is implied.
4. TSER is sampled on the falling edge of SYSCLK if the transmit side elastic store is enabled.
022697 47/48
DS2153Q
DS2153Q E1 SINGLE–CHIP TRANSCEIVER 44–PIN PLCC
E
E1
B
N
1
.075 MAX
D1
D
NOTE 1
CH1
.150
MAX
e1
E2
NOTE1: PIN 1 IDENTIFIER TO BE LOCA TED IN ZONE INDICATED.
INCHES
DIM MIN MAX
A 0.165 0.180 A1 0.090 0.120 A2 0.020
B 0.026 0.033 B1 0.013 0.021
C 0.009 0.012
CH1 0.042 0.048
D 0.685 0.695
D1 0.650 0.656 D2 0.590 0.630
E 0.685 0.695 E1 0.650 0.656 E2 0.590 0.630 e1 0.050 BSC
N 44
D2
B1
C
A
A1A2
022697 48/48
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