NSC DS92UT16TF

DS92UT16TUF
UTOPIA-LVDS Bridge for 1.6 Gbps Bi-directional Data
Transfers
1.0 General Description
The DS92UT16 is a flexible UTOPIA to LVDS Bridge device.
The LVDS Bridge transparently transports the UTOPIA bus
over a high speed LVDS serial link. The device includes
many reliability features such as an optional 1:1 protection
and built in bit error rate checking.
The parallel interface is user programmable for maximum
flexibility. The user can choose between UTOPIA Level Level
2 ATM layer (master) of PHY layer (slave). The UTOPIALVDS Bridge supports a special MPHY (multi-PHY layer)
operation mode. The MPHY operation supports up to 248
standard UTOPIA Level 2 PHY ports without adding external
circuitry.
The serial interface uses LVDS Serializer and Deserializer
technology. The 16:1 bit serialization allows conveying the
full-duplex parallel bus over two differential transmission
pairs. This enables low cost backplanes and cables. Cable
transmission length can be as long 16 meters.
The serial link carries Flow control information (back pressure) in both directions. The Bridge device applies back
pressure on a per queue basis over the 31 internal FIFO
queues. In addition, the serial link includes an OAM (Operations and Maintenance) channel that does not detract from
link performance.
There are many applications where the UTOPIA-LVDS
Bridge simplifies designs. Box-to-box connections can use
DS29UT16 devices across cables. Access multiplexor applications can use the devices across a PCB backplane for
point-to-point and lightly loaded multidrop configurations.
2.0 Features
n 832 Mbps LVDS 16-bit serializer and deserializer
interface
— Suitable for cable, printed circuit board, and
backplane transmission paths
— 10m cable at max LVDS data rate and greater than
16m at min LVDS data rate
— Embedded clock with random data lock capability for
clock recovery
— PRBS (x31 + x28 + 1) based LVDS link BER test
facility
n
n
n
n
n
n
n
n
n
n
n
— Two independent LVDS receiver serial ports for
optional 1:1 protection
— Main and redundant LVDS transmit ports
— Loop timing capability enables LVDS recovered clock
to internally drive LVDS transmit clock
— Internal buffers allow maximum LVDS serial bit rate
independent of UTOPIA clock rate
Programmable UTOPIA interface
— UTOPIA Level 2 up to 52 MHz
— ATM layer or PHY layer interface
— ATM layer interface can support up to 248 standard
Level 2 PHY ports with no additional external
circuitry. Configured as 31 MPHY’s, each with up to 8
sub-ports
— Supports extended cell size up to 64 bytes
— Supports 16- or 8-bit data buses with parity
Embedded bidirectional, non-blocking flow control over
serial link for per MPHY back pressure
No external memories required
Embedded OAM channel over serial link
— Remote Alarm/Status Indications
— Link Trace Label
— Embedded Control Channel with flow control for
software communication
— BIP16 based error performance monitoring
— In protected systems, the standby link OAM channel
is available for embedded communications and
performance/alarm monitoring
Multiple loop-back options
Standard microprocessor interface (Intel and Motorola
compatible)
IEEE 1149.1 JTAG port
Temperature range: −40˚C to +85˚C
CMOS technology for low power
LVDS transceiver section uses 3.3V power supply.
Digital UTOPIA section uses 2.5V power supply. All I/O
are 3.3V tolerant.
196 LBGA package, 15x15x1.37 mm, 1.0 mm ball pitch
3.0 Ordering Information
Order Number
Package Information
Package Number
DS92UT16TUF
196 LBGA package, 15x15x1.37 mm, 1.0 mm ball pitch
NUJB0196
© 2004 National Semiconductor Corporation
DS200316
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DS92UT16TUF UTOPIA-LVDS Bridge for 1.6 Gbps Bi-directional Data Transfers
February 2004
DS92UT16TUF
4.0 Block Diagram
20031601
FIGURE 1. DS92UT16 Block Diagram
5.0 Application Overview
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DS92UT16TUF
5.0 Application Overview
(Continued)
20031602
FIGURE 2. Application Example
The UTOPIA interface [1. See Section 21.0 References] is
an established standard for connecting Physical Layer devices to ATM Layer devices. However, when the ATM Layer
device and the Physical Layer device(s) are on separate
cards within a piece of equipment, or even on separate
equipment, then the parallel nature of this standard becomes
a limiting factor. See Figure 2.
The solution is to use the DS92UT16, which is a transparent
bridge that extends the UTOPIA bus over a serial LVDS
interface, and is suitable for backplanes and cables. Full
bidirectional flow control is incorporated, allowing backpressure to be applied to the source of the ATM cells. The 31
PHY ports available with standard UTOPIA Level 2 may be
extended to 248 ports without additional external circuitry.
The DS92UT16 achieves this by providing as many as 8
ENB and CLAV signals in both receive and transmit directions when acting as the ATM Layer device. This allows
addressing 248 PHYs that are configured as up to 31 ports
that each have as many as 8 sub-ports.
To aid equipment management and maintenance, the
DS92UT16 passes an embedded ‘Operations, Administration and Maintenance’ (OAM) channel over the serial link. In
addition, the device provides a number of loopback options
that are both traffic affecting (line loopbacks) and non-traffic
affecting (cell loopbacks), which simplify testing and diagnostic activities.
The DS92UT16 has a modified Bus LVDS serial output for
driving cables in point-to-point applications. The cable length
depends on the quality of the cable and the data rate.
Increasing the cable quality, or lowering the LVDS data rate,
increases the maximum possible cable length the device will
drive.
When examining the trade-offs that determine the
DS92UT16 maximum cable drive capability, it is important to
understand that the LVDS data rate on the cable is 18 times
(16 bits plus 2 embedded clock bits) the LVDS_TxClk rate.
For example, a 35 MHz LVDS_TxClk will produce a
630 Mbps data rate, and a 52 MHz clock will produce a
936 Mbps data rate. When using twinaxial grade differential
cable, the cable length can be as long as 16m for the
35 MHz clock and approximately 10m for the 52 MHz clock.
6.0 Functional Description
6.1 UTOPIA INTERFACE
The DS92UT16 has an industry standard UTOPIA interface
[1.] supporting Level 2 and Extended Level 2 operation.
Depending on its position in the bridge link, it may operate as
either the ATM layer or the physical layer in the UTOPIA
protocol.
In Level 2 mode, this interface can be either a 16-bit or an
8-bit wide data path, with both octet and cell level handshaking and operating at a frequency as high as 52 MHz, facilitating 622 Mbps (STM4/OC12) line rates.
In UTOPIA Level 2 mode, the device supports Multi-PHY
(MPHY) operation, whereby up to 31 PHY ports may be
connected to an ATM device. The presence of cells and
availability of buffer space is indicated using the CLAV signals.
UTOPIA Level 2 defines 1 ENB and 1 CLAV signal in each
direction. The DS92UT16 has extended this to 8 ENB and 8
CLAV signals, which enables up to 248 PHY ports to be
connected to an ATM device without additional external circuitry as shown in Figure 3.
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DS92UT16TUF
6.0 Functional Description
(Continued)
20031603
Note: The full connections for a single sub-port are shown in Figure 4.
FIGURE 3. Extended UTOPIA Level 2 for 248 PHY Ports
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DS92UT16TUF
6.0 Functional Description
(Continued)
20031627
FIGURE 4. Detailed Connection of One Sub-Port for Extended UTOPIA Level 2
• Standard UTOPIA Level 2 with 1 CLAV signal.
— One CLAV polling 31 PHY ports.
• DS92UT16 Extended UTOPIA Level 2 with up to 8 CLAV
signals.
— Each CLAV can poll 31 PHY ports giving a total of 248
PHY ports.
Multiple UTOPIA-LVDS bridge devices can be used in parallel to share up to 31 PHY ports among PHYs that are on
separate line cards Figure 5. Each of these ports may have
up to 8 sub-ports. There are constraints on the number of
port addresses used per bridge in such a configuration. See
Section 9.2 MULTIPLE BRIDGE MTB CONFIGURATION
For the purposes of queueing, the 248 PHY ports are configured as sub-ports of the standard 31 ports so each port/
queue has 8 sub-ports as discussed in Section 6.2.2 UpBridge Multi-Port Traffic Buffer. Each MPHY address
corresponds to a port.
The 5 bit MPHY can address up to 31 PHY ports. At least 3
additional bits are required to give the total of 8 bits necessary for addressing 248 PHY ports. These additional address bits can be provided by the user in any of the User
Prepend, Cell Header or UDF1/2 bytes of the cell as shown
in Figure 6. The DS92UT16 is configured to extract/insert the
extra address bits from/to any of these bytes.
PHY polling may be carried out as follows:
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DS92UT16TUF
6.0 Functional Description
(Continued)
20031604
Note: Default MTB queue thresholds must be changed to use this configuration. See Section 9.2 MULTIPLE BRIDGE MTB CONFIGURATION
FIGURE 5. Multi-Bridge System Example
Parity generation and checking is available in all modes.
To support systems where routing tags and/or padding are
added to the ATM cells at a previous device, the UTOPIA
interface on DS92UT16 may be programmed to handle nonstandard ATM cells of length 52 bytes up to 64 bytes. See
Figure 6. In all cases, the Start Of Cell (SOC) signal must
correspond to the first byte or word of the extended cell.
Back-to-back cell transfer is supported in all modes.
When configured as an ATM layer device, receive polling
and transmit polling of those Ports with queued cells is
Round-Robin. The DS92UT16 will only poll those PHY ports
configured as active.
LVDS link as described in Section 6.3.5 Flow Control.
Should any queue reach this upper threshold, back-pressure
is applied via the flow control mechanism over the serial link
to the down-bridge (transmitting) device which uses the
normal UTOPIA flow control handshaking to prevent any
more cells being transferred and thus prevent overflow.
The individual queue per port architecture ensures that the
flow control is non-blocking across the 31 ports. However,
the 8 sub-ports within each port can be blocking.
Furthermore, as is the nature of link-list buffers, each queue
may be over-assigned memory space, working on the assumption that not every queue will back up simultaneously.
To accommodate the rare occasions where the buffer as a
whole approaches full but individual queues are below their
full threshold, the device also compares the overall buffer fill
against a threshold. The flow control mechanism provides a
global ‘halt’ command to ensure that no cells will be lost if the
overall buffer should approach the overflow condition.
6.2 TRAFFIC BUFFERS
6.2.1 Down-Bridge FIFO
In the down-bridge direction, a simple 3 cell FIFO (with 30
cell overhead) is used to rate adapt the data from the UTOPIA clock domain to the LVDS clock domain for transmission. Per port queuing and back pressure/flow control is
handled by the corresponding up-bridge Multi-port Traffic
Buffer in the far end DS92UT16 device as described in
Section 6.2.2 Up-Bridge Multi-Port Traffic Buffer and Section
6.3.5 Flow Control.
6.3 TRANSMISSION CONVERGENCE SUB-LAYER
(TCS)
In the down-bridge direction, the Transmission Convergence
Sub-layer (TCS) Assembler performs cell rate de-coupling.
The TCS Assembler then prepares the cells for transport
over the LVDS link by packaging them within link Transport
Containers (TC).
In the up-bridge direction, the TCS Disassemblers unpack
the link transport containers and route the cells to the Multiport Traffic Buffer.
MPHY address, flow control, and OAM information is embedded within the link transport containers.
6.2.2 Up-Bridge Multi-Port Traffic Buffer
In the up-bridge direction, a 160 cell linked list buffer is
shared across up to 31 port queues. This is called the
Multi-port Traffic Buffer. Although each MPHY may be connected to 8 sub-ports/PHY’s, the MTB has a single queue
per MPHY port, as it only uses the 5-bit MPHY address and
does not access the sub-port address bits.
Each port has a programmable upper fill threshold. In the
up-bridge direction, queue overflow is avoided through the
means of a per queue flow control protocol embedded in the
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TABLE 1. PDU Cell Format Options
(Continued)
6.3.1 Cell Rate Decoupling
Field
In the down-bridge direction, the TCS Assembler inserts idle
cells when no valid traffic cells are available from the FIFO
for onward transmission. In the up-bridge direction, the TCS
Disassembler rejects all received idle cells.
6.3.2 Link Transport Container (TC)
The ATM cells received on the UTOPIA interface can be
standard or user-specified cells. Cell length is programmable
from 52 to 64 bytes. These cells are treated as Protocol Data
Units (PDU), which are packaged into Transport Containers
(TC) for transmission over the serial link. In the reverse
direction, the cell PDUs are unpacked from the link TCs
before being passed out on the UTOPIA interface.
This is illustrated in Figure 6.
Fixed/
Variable
Bytes
User Prepend
Variable
0, 2, 4, 6, 8, 10, 12
Cell Header
Fixed
4
UDF1/2
Variable
(On/Off)
2, 0 in 16 bit mode
1, 0 in 8 bit mode
Payload
Fixed
48
User Append
Variable
0, 2, 4, 6, 8, 10, 12
Although the UDF1/2 bytes will always be present, the
DS92UT16 can be programmed to either transport these
bytes or ignore them. If they are to be ignored, then the TCS
strips them out in the down-bridge direction and the UTOPIA
up-bridge section inserts a HEC byte in UDF 1. Otherwise,
they can be transported transparently the same as any other
PDU byte.
The PDU fields are configured as shown in Table 1. The total
PDU cell length must be in the range of 52 to 64 bytes. In
addition, variable length fields must be programmed to an
even number of bytes because the DS92UT16 operates with
an internal 16 bit data path. The total number of bytes
defined for User Prepend plus UDF1/2 and User Append
must not exceed 12 bytes to maintain the maximum PDU cell
length of 64 bytes.
20031605
FIGURE 6. PDU and Link Transport Container Format
At the other end of the link, this byte is used to route the
incoming PDU from the LVDS interface to the appropriate
MPHY port queue.
Each link TC has an MPHY address byte, two Flow Control
(F) Channel bytes, and a HEC byte in addition to the PDU
cell. The two F1 and F2 bytes per TC constitute the F
Channel, which is used for flow control and OAM purposes
over the link. The TCS uses the HEC byte for container
delineation, frame delineation, and cell header error detection.
6.3.4 Transport Container Delineation and Error
Monitoring
In the down-bridge direction, the device calculates and inserts the HEC byte using the CRC-8 polynomial x8 + x2 + x
+ 1 and optional coset x6 + x4 + x2 + 1 defined in I.432.1 [2.].
The HEC byte is calculated over the preceding 7–19 bytes,
which make up the link TC header. To aid delineation at the
far end, the entire contents of the TC, excluding the HEC,
are scrambled and the HEC is calculated on the scrambled
TC header. A scrambler using the pseudo-random sequence
polynomial x31 + x28 + 1 defined in I.432.1 [2.] is used.
In the up-bridge direction, the device determines the cell
delineation within the received data by locking onto the HEC
byte within the transport container, using the algorithm specified in I.432.1 [2.].
6.3.3 MPHY Tagging and Routing
In the down-bridge direction, the DS92UT16 adds an additional byte (MPHY byte) to each PDU. It contains the MPHY
port address associated with that PDU, as shown in Table 2.
TABLE 2. MPHY Byte
Bit
Function
7
6
5
4
3
MPHY Port Address 0–31
2
1
0
Reserved
7
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DS92UT16TUF
6.0 Functional Description
DS92UT16TUF
6.0 Functional Description
Since a regular flow control opportunity is provided via the
F1/F2 bytes of the F Channel, only a small amount of headroom need be reserved to allow for latency in this protocol.
Furthermore, should a number of PHY ports approach their
limit simultaneously and/or the overall buffer approach a
defined global threshold, a global halt may be issued, temporarily blocking all traffic.
The global halt/send command also allows the user to safely
maximize the use of the shared buffer by over-assigning the
memory among the Ports.
The flow control command is illustrated in Table 3. Each port
is assigned a control bit in specified F-bytes within the frame
structure, as shown in Section 6.3.6 F Channel Byte Usage
Within the Frame. Within the F byte logic, 1 represents a
‘halt’ command to that port and logic 0 represents a ‘send’
command. A global halt is indicated by all ports containing a
halt command. The msb of Flow Control 3 byte is reserved.
(Continued)
During normal operation in the up-bridge direction, the device monitors the HEC bytes for errors, with an option to
reject cells containing errored HEC’s. A performance metric
on the number of errored cells detected is maintained.
Although the HEC byte normally over-writes the UDF1 byte
before cells are passed out over a physical medium, the
DS92UT16 has the option to retain the UDF1 and UDF2
information fields in order to provide a truly transparent
UTOPIA bridge. If it is not necessary to pass the UDF1/2
bytes between the ATM and PHY devices at either end of the
link, then the user has the option to suppress them to improve link efficiency.
Furthermore, in order to easily share-out the F Channel
bandwidth between flow control and various OAM functions,
the DS92UT16 uses a frame structure as shown in Section
6.3.6 F Channel Byte Usage Within the Frame. A frame
contains 56 transport containers with ATM cells. The start of
frame is indicated by the HEC byte of TC0, which has had
the coset x6 + x4 + x2 + 1 added to it. This differentiates the
start of frame HEC from the normal cell HEC’s.
TABLE 3. Flow Control Coding Within the F Bytes
Flow
Control 3
Flow
Control 1
Flow
Control 0
Res Ports 30–24 Ports 23–16 Ports 15–8 Ports 7–0
6.3.5 Flow Control
The flow control mechanism within the DS92UT16 enables
applying back-pressure to the source of the ATM cells in both
directions. The flow control works independently per queue
for all 31 queues. It uses a simple ‘halt/send’ command per
PHY Port. At the destination buffer, the fill level of each Port
queue is examined against a programmed threshold. Should
the threshold be reached, a halt command is returned to the
source, which prevents any more cells being sent to that Port
until a ‘send’ command is subsequently received. Only the
Port in question is affected, so this is a non-blocking protocol
over the normal 31 Ports. However, the 8 sub-ports within a
Port do not have individual flow control. This means a subport can block other sub-ports within that Port.
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Flow
Control 2
6.3.6 F Channel Byte Usage Within the Frame
For the majority of time, the F Channel F1/F2 bytes are used
as a flow control opportunity, providing a rapid throttle-back
mechanism as described in Section 6.3.5 Flow Control. In
addition, a small number of F bytes are stolen in a regular
fashion to provide a low bandwidth OAM channel. This is
controlled by the TC number within the frame, as illustrated
in Table 4. Hence, an OAM channel is formed by the F1/F2
bytes in TCs 6, 13, 20, 27, 34, 41, 48 and 55, with the F1/F2
bytes in the remaining containers forming a flow control
signalling channel.
8
(Continued)
TABLE 4. F Channel Byte Usage Within the Frame
TC0
Flow Control 3
Flow Control 2
TC1
Flow Control 1
Flow Control 0
TC2
Flow Control 3
Flow Control 2
TC3
Flow Control 1
Flow Control 0
TC4
Flow Control 3
Flow Control 2
TC5
Flow Control 1
Flow Control 0
TC6
Alarm/Sig.
Link Labels
TC7
Flow Control 3
Flow Control 2
TC8
Flow Control 1
Flow Control 0
TC9
Flow Control 3
Flow Control 2
TC10
Flow Control 1
Flow Control 0
TC11
Flow Control 3
Flow Control 2
TC12
Flow Control 1
Flow Control 0
TC13
ECC1
ECC2
TC14
Flow Control 3
Flow Control 2
TC15
Flow Control 1
Flow Control 0
TC16
Flow Control 3
Flow Control 2
TC17
Flow Control 1
Flow Control 0
TC18
Flow Control 3
Flow Control 2
TC19
Flow Control 1
Flow Control 0
TC20
ECC3
ECC4
TC21
Flow Control 3
Flow Control 2
TC22
Flow Control 1
Flow Control 0
TC23
Flow Control 3
Flow Control 2
TC24
Flow Control 1
Flow Control 0
TC25
Flow Control 3
Flow Control 2
TC26
Flow Control 1
Flow Control 0
TC27
BIP16
TC28
Flow Control 3
Flow Control 2
TC29
Flow Control 1
Flow Control 0
TC30
Flow Control 3
Flow Control 2
TC31
Flow Control 1
Flow Control 0
TC32
Flow Control 3
Flow Control 2
TC33
Flow Control 1
Flow Control 0
TC34
Reserved
TC35
Flow Control 3
Flow Control 2
TC36
Flow Control 1
Flow Control 0
TC37
Flow Control 3
Flow Control 2
TC38
Flow Control 1
Flow Control 0
TC39
Flow Control 3
Flow Control 2
TC40
Flow Control 1
Flow Control 0
TC41
ECC5
ECC6
TC42
Flow Control 3
Flow Control 2
TC43
Flow Control 1
Flow Control 0
TC44
Flow Control 3
Flow Control 2
TC45
Flow Control 1
Flow Control 0
TC46
Flow Control 3
Flow Control 2
TC47
Flow Control 1
Flow Control 0
TC48
ECC7
ECC8
TC49
Flow Control 3
Flow Control 2
TC50
Flow Control 1
Flow Control 0
TC51
Flow Control 3
Flow Control 2
TC52
Flow Control 1
Flow Control 0
TC53
Flow Control 3
Flow Control 2
TC54
Flow Control 1
Flow Control 0
TC55
BIP16
A and in RBRA for receive port B. See Section 18.33 RECEIVE PORT A REMOTE STATUS AND ALARMS — 0x3C
RARA and Section 18.52 RECEIVE PORT B REMOTE STATUS AND ALARMS — 0x7C RBRA for descriptions of these
registers.
The function of the ECC signaling bits EVN, ESSA, and
ESSB is described in Section 16.0 Embedded Communication Channel Operation.
6.3.7 OAM Channel
6.3.7.1 Remote Alarm and Signaling Byte
A byte-wide remote alarm and signaling channel is carried in
the F1 byte in TC6 as shown in Section 6.3.6 F Channel Byte
Usage Within the Frame. This provides a means for the
device at the far end of the LVDS link to signal an alarm
condition to the near end and vise-versa. This byte also
contains the ECC flow control signals. The format of this byte
is as shown below. Bit [0] is reserved.
6.3.7.2 Link Trace Label Byte
Also, in TC6 a byte-wide link trace label is carried in the F2
byte as shown in Section 6.3.6 F Channel Byte Usage Within
the Frame. This allows the user to verify link connectivity,
which is especially useful when a number of cable links are
being used. The DS92UT16 may be programmed with both
a link label value to transmit and an expected link label.
Should the received link label not match the expected value,
an alarm interrupt may be raised.
The received Link Label byte is software accessible and an
interrupt may be raised on a change of received Link Label
byte. So the Link Label byte may also be used as a user
defined channel to pass one byte per frame across the link.
TABLE 5. Remote Alarm and Signalling Byte
Bit
Function
7
6
5
4
3
RLOSA
RLOSB
RBA
RDSLL
EVN
2
1
ESSA ESSB
0
Res
• RLOSA Remote Loss Of Signal lock at far end device
receive port A.
• RLOSB Remote Loss Of Signal lock at far end device
receive port B.
Remote far end device active receive port. Set =
• RBA
remote receive port B active and Clear = remote
receive port A active.
• RDSLL Remote far end device active port Descrambler
Loss of Lock. Set = Out of lock and Clear = In
lock.
ECC Tx Data Valid/Null indication.
• EVN
• ESSA ECC RxA Stop/Start indication.
• ESSB ECC RxB Stop/Send indication.
The status of the received RLOSA, RLOSB, RBA and
RDSSL bits is reflected in the RARA register for receive port
6.3.7.3 Embedded Communications Channel (ECC)
An Embedded Communications Channel is provided over
the link for software messaging, download, etc. in the F1/F2
bytes of TCs 13, 20, 41 and 48 as shown in Table 4. The
ECC byte contents are not processed by the DS92UT16.
Hence the DS92UT16 is transparent to and does not restrict
the system messaging protocol.
The ECC consists of an 8 byte Tx Buffer with corresponding
Tx Buffer Ready and Tx Buffer Send flags, and an 8 byte Rx
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DS92UT16TUF
6.0 Functional Description
DS92UT16TUF
6.0 Functional Description
Transport Containers per Frame as 56. It then shows the
number of bytes in each Frame for OAM and Flow Control.
There is a total of 112 bytes in each Frame for the F
Channel.
(Continued)
Buffer with a corresponding Rx Buffer Full Flag. All bytes of
the buffers are software read/write accessible. Tx Buffer
Ready is read only.
At the ECC transmit side, the reset state sets the Tx Buffer
Ready flag and clears the Tx Buffer Send flag. Then the
software assembles a message for transmission in the Tx
Buffer. To send a message, the software simply sets Tx
Buffer Send, which automatically clears Tx Buffer
Ready. The contents of the Tx Buffer are transmitted to the
far-end. The Tx Buffer will automatically be retransmitted
until the far-end indicates that it has been successfully received. When notified by the far end of successful reception,
Tx Buffer Ready is set and an interrupt raised to the software
to indicate successful transmission. A new message may
now be assembled in the Tx Buffer and transmitted by
setting Tx Buffer Send. As all the Tx Buffer bytes are read/
write, the message to be transmitted can be assembled in
any order and read back by the software before transmission. The same message can be retransmitted simply by
setting Tx Buffer Send again.
Table 7 shows the bit rate used by each portion of the F
Channel. The larger 68 byte container uses a lower proportion of the channel bandwidth for F Channel functions.
Table 8 shows the percentage of the channel bandwidth
used for each of the functions. The total F Channel bandwidth is only 3.57% of total bandwidth even with the smaller
container size.
TABLE 6. F Channel Bandwidth — Bytes
At the ECC receive side, the reset state clears the Rx Buffer
Full flag. When all 8 bytes of a message have been successfully received and stored in the Rx Buffer, the Rx Buffer Full
flag is set and an interrupt raised. As all the Rx Buffer bytes
are read/write, the message can be read in any order by the
software. A new message will not overwrite the current received message until the Rx Buffer Full flag is cleared by the
software indicating that the current Rx Buffer has been read
and a new message can be received.
The ECC data flow is controlled across the link using the
EVN, ESSA, and ESSB bits of the Remote Alarm and Signaling byte (Section 6.3.7.1 Remote Alarm and Signaling
Byte).
As there are two independent LVDS receive ports, the
DS92UT16 has two independent ECC receive sections.
These are assigned to the LVDS receive ports Port A and
Port B. The ECC of the standby link may therefore be used
for software communication.
Section 16.0 Embedded Communication Channel Operation
describes the operation and control of the ECC in detail.
56
Bytes per Frame for Remote Alarms and
Signalling
1
Bytes per Frame for Link Label
1
Bytes per Frame for ECC
8
Bytes per Frame Reserved
2
Bytes per Frame for BIP16
4
Bytes per Frame for OAM
16
Bytes per Frame for Flow Control
96
Bytes per Frame for F Channel
112
TABLE 7. F Channel Bandwidth — Mbps
6.3.7.4 BIP16
A Bit-Interleaved-Parity mechanism provides a live error performance metric on the LVDS link. A BIP16 value is calculated over a previous block of 28 containers and inserted in
the F1/F2 bytes of containers 27 and 55, as shown in Section 6.3.6 F Channel Byte Usage Within the Frame. At the far
end, the re-calculated BIP16 values are compared against
the received values. Any bit errors in this comparison are
counted. Should the number of errors exceed a programmed
threshold, then an interrupt may be raised.
Link BW - Mbps
800
800
Container Size - Bytes
56
68
Remote Alarm BW - Mbps
0.26
0.21
Link Label BW - Mbps
0.26
0.21
ECC BW - Mbps
2.04
1.68
Reserved BW - Mbps
0.51
0.42
BIP16 BW - Mbps
1.02
0.84
OAM BW - Mbps
4.08
3.36
Flow Control BW - Mbps
24.49
20.17
F Channel BW - Mbps
28.57
23.53
TABLE 8. F Channel Bandwidth — Percentage
6.3.7.5 F Channel (Flow Control and OAM) Bandwidth
Analysis
This section analyses the bandwidth used by the various
components of the F Channel. The figures are dependent
upon the link bandwidth and the size of the PDU/ATM cells
being carried in the Transport Containers. This illustration is
restricted to 800 Mbps and PDU sizes of 52 and 64 bytes. By
adding the 4 bytes for the F Channel, the TCs are then 56
and 68 bytes respectively.
Table 6 illustrates the number of bytes used for each function
in the F Channel. The top row gives the total number of
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Number of Transport Containers in Frame
(8 rows x 7 columns)
Link BW - Mbps
800
800
Container Size - Bytes
56
68
Remote Alarm BW%
0.03
0.03
Link Label BW%
0.03
0.03
ECC BW%
0.26
0.21
Reserved BW%
0.06
0.05
BIP16 BW%
0.13
0.10
OAM BW%
0.51
0.42
Flow Control BW%
3.06
2.52
F Channel BW%
3.57
2.94
6.4 LVDS PHYSICAL INTERFACE
The DS92UT16 provides one dual transmit and two independent receive high speed LVDS serial interfaces with 800
Mbps bandwidth. The LVDS Interface transmits and receives
data over lightly loaded backplanes or up to 10m of
cable. The single transmit block drives two pairs of differen10
device configuration registers such as PDU cell length, UTOPIA interface mode, etc. are protected in this way. All other
registers associated with the ECC, performance monitoring
and interrupts are always write accessible by the software
except as noted in next paragraph. See Section 18.1 SOFTWARE LOCK — 0x00 to 0x01 SLK0 to SLK1.
(Continued)
tial outputs with independent TRI-STATE ® controls for each.
The same data is transmitted over both pairs of transmit
pins. The two serial receive interfaces are completely separate and independent and are denoted Port A and Port B.
Only one receive port is selected for traffic at any one
time. This is designated the Active Port. The Standby receive
port may be powered down. Alternatively, the Standby receive port’s OAM channel can be made available for software communications using the ECC, and for link performance monitoring. This allows the condition of the Standby
link to be determined. The LOCK status of both Active and
Standby ports is monitored automatically.
TABLE 9. Software Lock Sequences
Meaning
Unlock Sequence
LOCK Sequence
The transmitted data stream contains embedded clock information. The receiver’s clock recovery circuit locks onto the
embedded clock in either a random data pattern, or by
instructing the transmitter to send SYNCH patterns. The
DS92LV16 can send SYNCH patterns on power-up or when
synchronization is lost. The latter option requires a feedback
loop in either hardware or software between the transmitter
and the receiver, but has the benefit of a faster lock time. The
LOCK status of both receive ports is reflected on external
pins and alarm/status bits that are readable via the microprocessor port. The LOCK status, along with the currently
active port, is transmitted to the far-end receiver via the
Remote Alarm and Signalling byte of the OAM channel as
described in Section 6.3.7.1 Remote Alarm and Signaling
Byte. The recovered clocks of both receive ports are available on external pins.
A Loop Timing option is available whereby the LVDS transmit
clock can be sourced directly from the recovered clock of the
active receiver, rather than from the external transmit clock
input pin.
The transmit port and two receive ports may be independently powered down via microprocessor control. Similarly,
the device may be forced to send SYNCH patterns on the
transmit port via microprocessor control.
To assist in designer testing and system commissioning of
the LVDS interface, the DS92UT16 has a built in BER test
facility. The device may be configured to send a PRBS
pattern in place of ATM cells. At the receiver, the device locks
onto this PRBS pattern and provides an error metric.
Sequence
Address
Data
1st write
0x00
0x00
2nd write
0x01
0xFF
1st write
0x00
0xDE
2nd write
0x01
0xAD
Powering down a Receive Port inhibits access to the associated registers. This feature saves power when a Receive
Port is not in use. It allows re-reading the last value read
from a register associated with that Receive Port and disallows writing to registers. Receive Port A (RxA) in Powerdown mode inhibits access to registers described in Section
18.21 RECEIVE PORT A LINK LABEL — 0x20 RALL to Section 18.39 RECEIVE PORT A BIT ERROR COUNT — 0x43
to 0x45 RABEC2 to RABEC0. Receive Port B (RxB) in
Power-down mode inhibits access to registers described in
Section 18.40 RECEIVE PORT B LINK LABEL — 0x60 RBLL
to Section 18.58 RECEIVE PORT B BIT ERROR
COUNT — 0x83 to 0x85 RBBEC2 to RBBEC0. The contents
of these registers are not lost or altered in Power-down
mode.
6.6 PERFORMANCE MONITORING AND ALARMS
The DS92UT16 provides a number of performance metrics
and alarms to assist in equipment/network management.
The programmer can independently enable or disable these
alarms to raise an interrupt. See Section 14.0 Performance
Monitoring for a detailed description of the Performance
Monitoring and General Alarms.
6.7 TEST INTERFACE
The IEEE 1149.1 JTAG [4.] port on the device provides
access to the built-in test features such as boundary SCAN,
Internal SCAN and RAM BIST. It may be used to test the
device individually or as part of a more comprehensive circuit board or system test. (NOTE: The internal SCAN and
RAM BIST functions are not intended for user access.
Therefore, the device user should never assert the Test_se
pin.)
6.5 CPU INTERFACE
The DS92UT16 contains a flexible microprocessor port capable of interfacing to any common system processor. Via
this port, the system software can customize the behavior of
the device from the various options provided, monitor the
system performance, and activate diagnostic facilities such
as loop-backs and LVDS BER testing.
In addition to an 8-bit address and 8-bit data bus plus the
associated bus protocol control signals, the port includes an
open-drain interrupt signal. The device may assert this signal
on the detection of various alarms within the device, such as
excessive HEC errors, ECC buffer full/empty, loss of lock
etc. Any of the potential internal sources of this interrupt may
be inhibited individually via an interrupt mask.
A software lock mechanism is implemented to prevent spurious modification of some of the DS92UT16 software accessible registers. A predefined UNLOCK write sequence is
necessary to allow unrestricted software write access to the
DS92UT16. A corresponding LOCK write sequence will prevent any software write access to the these registers. Read
access is unrestricted except as noted in the next paragraph.
See Table 9 for the LOCK and UNLOCK sequences. Only
6.8 LOOPBACKS
To assist in diagnostic testing, the device provides both
LVDS interface loopbacks and ATM cell loopbacks. The
former is suitable for designer or commission testing when
the device is not passing live traffic. The latter allows cell
trace testing on live traffic. The ATM cell loopback operates
by recognizing the user-defined cell header of the special
loopback cells. The available loopback options are shown in
Table 10.
In addition to providing a live round trip test via the cell
loopbacks, the DS92UT16 helps pinpoint failures between
transmit and receive paths by counting the number of loopback cells received.
All loopbacks are programmable via the microprocessor
interface.
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DS92UT16TUF
6.0 Functional Description
DS92UT16TUF
6.0 Functional Description
(Continued)
TABLE 10. Loopback Options
LineLB_LVDS
Physical loopback at the LVDS interface. Loop entering LVDS traffic back out of the device.
LocalLB_LVDS
Physical loopback at the LVDS interface. Loop exiting LVDS traffic back into the device.
Up2Down_ATM
ATM loopback. Route defined cell entering the device at the LVDS interface back out.
Down2Up_ATM
ATM loopback. Route defined cell entering the device at the UTOPIA interface back out.
20031606
FIGURE 7. LVDS Interface and ATM Cell Loopback Options
7.0 Signal Description
Package ball assignment in Section 20.0 Package
TABLE 11. Pin Description
Signal Name
Description
Width
Signal Type
BiDir (Note 2)
Polarity
Internal
Bias
UTOPIA INTERFACE
U_TxData [15:0]
Transmit toward the PHY Layer data bus.
16
U_TxParity
Transmit data bus parity bit. (odd parity)
1
BiDir (Note 2)
U_TxCLAV [7:1]
Transmit cell available - Extended.
7
Input (Note 3)
Active High
Pull Down
U_TxCLAV [0]
Transmit cell available - Normal/Extended.
1
BiDir (Note 1)
Active High
Pull Down
U_TxENB [7:1]
Enable Data transfers - Extended.
7
U_TxENB [0]
Enable Data transfers - Normal/Extended.
1
BiDir (Note 2)
Active Low
U_TxSOC
Transmit Start Of Cell.
1
BiDir (Note 2)
Active High
U_TxAddr [4:0]
Address of MPHY device being selected.
5
BiDir (Note 2)
U_RxData [15:0]
Receive from the PHY Layer data bus.
16
BiDir (Note 1)
U_RxParity
Receive data bus parity bit. (odd parity)
1
BiDir (Note 1)
U_RxCLAV [7:1]
Receive cell available - Extended.
7
Input (Note 3)
Active High
Pull Down
U_RxCLAV [0]
Receive cell available - Normal/Extended.
1
BiDir (Note 1)
Active High
Pull Down
U_RxENB [7:1]
Enable Data transfers - Extended.
7
U_RxENB [0]
Enable Data transfers - Normal/Extended.
1
BiDir (Note 2)
Active Low
U_RxSOC
Receive Start Of Cell.
1
BiDir (Note 1)
Active High
U_RxAddr [4:0]
Address of MPHY device being selected.
5
BiDir (Note 2)
U_UDBClk
UTOPIA Down Bridge - Input transfer clock.
1
Input (Note 4)
U_UUBClk
UTOPIA Up Bridge - Output transfer clock.
1
Input (Note 5)
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12
Output (Note 3) Active Low
Output (Note 3) Active Low
(Continued)
TABLE 11. Pin Description (Continued)
Signal Name
Description
Width
Signal Type
Polarity
Internal
Bias
LVDS INTERFACE
LVDS_ADout[+,−]
A Serial data differential outputs.
2
Output
LVDS_BDout[+,−]
B Serial data differential outputs.
2
Output
LVDS_ADenb
Serial transmit data A output enable.
1
Input
Active High
Pull Up
LVDS_BDenb
Serial transmit data B output enable.
1
Input
Active High
Pull Up
LVDS_Synch
External control to transmit SYNCH patterns on
serial interface.
1
Input
Active High
Pull Down
LVDS_TxClk
Transmit clock.
1
Input
LVDS_TxPwdn
Transmit section power down
1
Input
Active Low
Pull Up
LVDS_ADin[+,−]
PortA Serial data differential inputs.
2
Input
LVDS_ALock_n
PortA Clock recovery lock status
1
Output
LVDS_ARxClk
PortA Recovered clock.
1
Output
LVDS_ARefClk
PortA Reference clock for receive PLLs.
1
Input
Active Low
Pull Up
Pull Up
LVDS_APwdn
PortA Power Down.
1
Input
LVDS_BDin[+,−]
PortB Serial data differential inputs.
2
Input
LVDS_Block_n
PortB Clock recovery lock status.
1
Output
LVDS_BRxClk
PortB Recovered clock.
1
Output
LVDS_BRefClk
PortB Reference clock for receive PLLs.
1
Input
LVDS_BPwdn
PortB Power Down.
1
Input
Active Low
CPU & GENERAL CONTROL
CPU_cs
Select signal used to validate the address bus
for read and write data transfers.
1
Input
Active Low
CPU_rd (CPU_ds)
Read or Data Strobe, depending on
CPU_BusMode.
1
Input
Active Low
CPU_wr (CPU_rnw)
Write or Read/Write, depending on
CPU_BusMode.
1
Input
Active Low
(Write)
CPU_int
Interrupt request line.
1
Output
Active Low
CPU_Data[7:0]
Data bus.
8
BiDir
CPU_Addr[7:0]
Address bus.
8
Input
CPU_BusMode
Mode select for bus protocol.
1
Input
GPIO [3:0]
General Purpose Input/Output.
4
BiDir
Reset_n
Reset min pulse is 2X slowest clock period.
1
Input
Open Drain
Pull Down
Active Low
Pull Up
JTAG TEST INTERFACE
JTAG_CLK
Test clock.
1
Input
JTAG_Reset
Test circuit reset.
1
Input
JTAG_TMS
Test Mode Select.
1
Input
JTAG_TDI
Test Data In.
1
Input
JTAG_TDO
Test Data Out.
1
Output
Test_se
SCAN enable (for manufacturing test only)
1
Input
Active Low
Pull Up
Pull Up
Active High
Pull Down
TOTAL PIN COUNT
Total Functional I/O
133
LVDS VDD/VSS
3.3V LVDS power for analog and digital
46
CVDD/CVSS
2.5V Core Power for digital functions
6
IOVDD/IOVSS
3.3V I/O power ring
8
Total Power
60
No Connect
No signal connected to this pin
Total Pins
196 LBGA, 15x15 mm, 1.0 mm ball pitch
3
196
Note 1: These pins are Inputs in ATM Layer mode and Outputs PHY Layer mode
13
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DS92UT16TUF
7.0 Signal Description
DS92UT16TUF
7.0 Signal Description
(Continued)
TABLE 11. Pin Description (Continued)
Note 2: These pins are Outputs in ATM Layer mode and Inputs PHY Layer mode.
Note 3: These pins are only used in PHY layer mode, Extended 248 PHY mode. In Normal 31 PHY mode or ATM layer mode, they must be unconnected.
Note 4: In PHY layer mode this is the Utopia TxClk and in ATM layer mode this is the Utopia RxClk.
Note 5: In PHY layer mode this is the Utopia RxClk and in ATM layer mode this is the Utopia TxClk.
In 16-bit mode of the full U_TxData[15:0] and
U_RxData[15:0] are valid and parity is calculated over all
bits of the data buses.
8.0 UTOPIA Interface Operation
This section describes the operation of the UTOPIA Interface
of the DS92UT16. The UTOPIA interface mode of operation
is defined in the UTOPIA Configuration (UCFG) register
described
in
Section
18.59
UTOPIA
CONFIGURATION — 0xA0 UCFG. The format of the PDU
cells carried over this interface is defined in the PDU Configuration (PDUCFG) register described in Section 18.5 PDU
CONFIGURATION — 0x05 PDUCFG.
The interface can operate in ATM layer mode or PHY layer
mode. When operating as a Level 2 ATM layer interface, the
protocol can be extended to cope with up to 248 PHY ports
rather than the maximum 31 allowed by the standard Level 2
definition. This Extended Level 2 mode is achieved with
eight CLAV and eight ENB signals.
•
One ATM Layer can communicate with up to 31 PHY
ports using the MPhy address busses U_TxAddr[4:0] and
U_RxAddr[4:0] and the control signals U_TxCLAV[0],
U_RxCLAV[0], U_TxENB[0] and U_RxENB[0].
• U_TxCLAV[7:1], U_RxCLAV[7:1], U_TxENB[7:1] and
U_RxENB[7:1] are not used.
• All Queues from 30 to 0 of the MTB may be used. There
is one queue for each MPhy address so the use of the
queues will depend on the connected ports list defined by
the UCPL3–UCPL0 registers.
• Uses the connected ports list defined by the UCPL3UCPL0 registers. In ATM mode, these registers are used
to determine the ports that should be polled. In PHY
mode, these registers are used to determine which MPhy
addresses the device should respond to during polling.
• The connected sub-port list defined in the UCSPL register is not used.
• The sub-port address location defined by USPAL and
USPAM registers is not used.
• The CLAV mode bits CLVM[1:0] of the UCFG register
should be defined as CLVM[1:0] = 00.
The configuration of the inputs/outputs of the UTOPIA Level
2 interface for ATM Layer mode and PHY Layer mode is
shown in Figure 8. The main difference is that in ATM mode
the CLAV pins are inputs and the MPhy Address and ENB
pins are outputs; whereas in PHY mode, the CLAV pins are
outputs and the MPhy Address and ENB pins are inputs.
On power up the device defaults to ATM layer mode. To
prevent potential contention on the Utopia interface signals,
all the Utopia pins which are bidirectional are configured as
outputs in tri-state mode and the Utopia interface block is
disabled. The user must select the device operating mode,
ATM layer or PHY layer, by writing the appropriate value to
the UMODE bit of the UCFG register before enabling the
Utopia interface block and releasing the Utopia interface
pins. Enabling the Utopia interface and releasing the Utopia
pins is achieved by setting the UBDEN bit of the UCFG
register.
8.1 UTOPIA BASIC LEVEL 2 MODE - 31 PORTS
(Default Mode)
In UTOPIA Level 2 mode:
• 8-bit or 16-bit data buses are controlled by the BWIDTH
bit of the UCFG register. In 8-bit mode only
U_TxData[7:0] and U_RxData[7:0] are valid; parity is calculated and checked only over these bits of the data
buses and the upper bits of the data buses are not used.
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Note that in ATM Layer mode the DS92UT16 does not
generate the UTOPIA clocks and must be supplied with
these clocks just as in PHY mode.
14
DS92UT16TUF
8.0 UTOPIA Interface Operation
(Continued)
20031607
FIGURE 8. Basic UTOPIA Level 2 UMODE Configuration
buses. In 16-bit mode, the full U_TxData[15:0] and
U_RxData[15:0] are valid; parity is calculated and
checked over all bits of the data buses.
• In ATM mode, the DS92UT16 can communicate with up
to 248 PHY ports using the MPhy address busses
U_TxAddr[4:0] and U_RxAddr[4:0], and the control signals U_TxCLAV[7:0], U_RxCLAV[7:0], U_TxENB[7:0]
and U_RxENB[7:0]. In PHY mode, the DS92UT16 behaves as a standard Level 2 device and only 31 ports are
needed using the MPhy address busses U_TxAddr[4:0]
and U_RxAddr[4:0], and the control signals
U_TxCLAV[0], U_RxCLAV[0], U_TxENB[0] and U_RxENB[0].
• All Queues from 30 to 0 of the MTB may be used. There
is one queue for each MPhy address so the use of the
queues will depend on the connected ports list defined by
the UCPL3–UCPL0 registers.
• The connected ports list defined by the UCPL3–UCPL0
registers and the connected sub-port list defined in the
UCSPL register are used. In ATM mode, these registers
are used to determine which ports should be polled. In
PHY mode, these registers are used to determine which
MPhy addresses the device should respond to during
polling.
• The sub-port address location defined by USPAL and
USPAM registers is used in ATM mode to determine the
location of the 3-bit sub-port address in the PDU cell. In
PHY mode these registers are not used.
• The CLAV mode bits CLVM[1:0] of the UCFG register
should be defined as CLVM[1:0] = 11.
The configuration of the inputs/outputs of the UTOPIA Level
2 interface for ATM Layer mode and PHY Layer mode is
shown in Figure 9.
8.1.1 ATM Polling
When configured as an ATM Layer device, the DS92UT16
polls the connected PHY ports using the MPhy address
busses U_TxAddr and U_RxAddr. Only those ports which
are connected will be polled. The connected ports list defined in the UCPL3–UCPL0 registers is used to determine
which ports are connected. The PHY ports respond only on
U_TxCLAV[0] and U_RxCLAV[0]. On reset the
UCPL3–UCPL0 registers are all set to 0xFF so the
DS92UT16 will poll all ports.
8.1.2 PHY Polling
When configured as a PHY Layer device the DS92UT16 is
polled by the connected ATM device. During polling the
DS92UT16 will only respond to MPhy addresses, on
U_TxAddr and U_RxAddr, which are defined as connected.
The connected ports list defined in the UCPL3–UCPL0 registers is used to determine which ports are connected. On
reset the UCPL3–UCPL0 registers are all set to 0xFF so the
DS92UT16 will respond to all MPhy addresses during polling. The DS92UT16 responds only on U_TxCLAV[0] and
U_RxCLAV[0].
NOTE: There must always be at least one connected port
defined in the UCPL3–UCPL0 registers. If no ports are to be
connected then use Configuration Traffic Inhibit mode described in Section 10.0 Configuration and Traffic Inhibit Operation.
8.2 UTOPIA EXTENDED LEVEL 2 MODE - 248 PORTS
In UTOPIA Extended Level 2 mode:
• 8-bit or 16-bit data buses are controlled by the BWIDTH
bit of the UCFG register. In 8-bit mode, only
U_TxData[7:0] and U_RxData[7:0] are valid; parity is calculated and checked only over these bits of the data
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DS92UT16TUF
8.0 UTOPIA Interface Operation
(Continued)
20031608
FIGURE 9. Extended UTOPIA Level 2 UMODE Configuration
The main difference is that in ATM mode the CLAV pins are
inputs and the MPhy Address and ENB pins are outputs,
whereas in PHY mode the CLAV pins are outputs and the
MPhy Address and ENB pins are inputs. Also, in ATM mode
all eight CLAV and ENB pins are used, but in PHY mode only
one of the CLAV and ENB pins are used.
Note that in ATM Layer mode the DS92UT16 does not
generate the UTOPIA clocks but must be supplied with these
clocks just as in PHY mode.
reset the UCPL3–UCPL0 registers are all set to 0xFF so the
DS92UT16 will respond to all MPhy addresses during polling.
NOTE: There must always be at least one connected port
defined in the UCPL3–UCPL0 registers. If no ports are to be
connected then use Configuration Traffic Inhibit mode described in Section 10.0 Configuration and Traffic Inhibit Operation.
8.2.3 Sub-Port Address
The operation of the sub-port address is illustrated in Figure
10. To use the Extended Level 2 mode that allows addressing up to 248 Ports, the ATM Layer (that which drives the
DS92UT16 in PHY mode) must be capable of inserting a
three bit sub-port address in the PDU cell for use by the
DS92UT16. This 3-bit sub-port address must reside in either
the User Prepend, Cell Header, or UDF bytes. It’s location is
defined in the UTOPIA Sub-Port Address Location (USPAL)
and UTOPIA Sub-Port Address Mask (USPAM) registers.
The USPAL register defines which byte of the User Prepend,
Cell Header, or UDF, contains the address and the USPAM
register defines which three bits of that byte are the sub-port
address.
Transmit Path Example: The MPhy address is interpreted
as the Port address. So, a cell destined for the PHY designated as Port 0 Sub-Port 7 has the three bit sub-port address
7 (binary “111”) inserted into the defined sub-port address
location of the PDU cell by the ATM layer head-end. It is then
transmitted to the DS92UT16 in PHY mode using MPhy
address 0. The DS92UT16 in PHY mode does not examine
the sub-port address because all cells are transmitted downbridge anyway.
At the far end, the DS92UT16 in ATM mode extracts the
sub-port address. This is used to determine which sub-port
CLAV/ENB signals the destination PHY is connected to. A
8.2.1 ATM Polling
When configured as an ATM Layer device, the DS92UT16
polls the connected PHY ports using the MPhy address
busses U_TxAddr and U_RxAddr. Only those ports which
are connected will be polled. The connected ports list defined in the UCPL3–UCPL0 registers is used to determine
which ports are connected. The PHY ports respond on
U_TxCLAV[7:0] and U_RxCLAV[7:0]. The MPhy address determines the Port and the CLAV pin number determines the
sub-port. Therefore up to 8 sub-ports may be connected to a
port. Polling of a single MPhy address will get eight responses on the eight CLAV lines. The DS92UT16 uses the
connected sub-port list defined in the UCSPL register to
determine which of these eight sub-port responses are valid.
On reset, the UCPL3–UCPL0 registers are all set to 0xFF
and the UCSPL register is set to 0x01, so the DS92UT16 will
poll all ports and assume only sub-port zero is connected.
8.2.2 PHY Polling
When configured as a PHY Layer device, the DS92UT16 is
polled by the connected ATM device. During polling, the
DS92UT16 will only respond to MPhy addresses on
U_TxAddr and U_RxAddr, which are defined as connected.
The connected ports list defined in the UCPL3–UCPL0 registers is used to determine which ports are connected. On
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DS92UT16TUF
8.0 UTOPIA Interface Operation
(Continued)
port address of 0 and a sub-port address of 7 means that the
destination PHY is MPhy address 0 attached to U_TxENB[7]
and U_TxCLAV[7]. The cell is then transmitted to that PHY.
20031609
FIGURE 10. Sub-Port Address Operation
Receive Path Example: The DS92UT16 in ATM mode receives a cell from the PHY with MPhy address 0 attached to
U_RxENB[6] and U_RxCLAV[6] and designates it as from
Port 0 Sub-Port 6. The DS92UT16 inserts the sub-port address 6 (binary “110”) into the sub-port address location of
the received PDU. Then this PDU is transmitted to the
head-end. The head-end ATM layer device must extract this
sub-port address from the PDU to determine the full address
of the originating PHY.
8.2.4 Connected Port and Sub-Port Lists
Figure 11 illustrates the usage of the connected port list
registers (UCPL3–UCPL0) and the connected sub-port list
register (UCSPL). In this case, the DS92UT16 in ATM mode
defines Port 1 and Sub-port 7 as not connected.
The UCPL3–UCPL0 registers contain 31 bits corresponding
to the 31 possible Ports addressed by the MPhy address
busses. If a bit location in the UCPL3–UCPL0 registers is
set, then that Port is connected. The sub-ports of the con-
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DS92UT16TUF
8.0 UTOPIA Interface Operation
Sub-port 2, Port 1 Sub-port 1, and Port 1 Sub-port 0 are not
connected. Port 1 will therefore, not be polled.
(Continued)
With bit 7 of UCSPL cleared, then sub-port 7 is not connected. This means that sub-port 7 for all possible 31 ports is
not connected. So Port 31 Sub-port 7, Port 30 Sub-port 7,
Port 29 Sub-port 7,......and Port 0 Sub-port 7 are not connected.
Therefore, clearing a bit in the UCPL3–UCPL0 registers will
disconnect 8 possible PHY port locations and clearing a bit
in the UCSPL register will disconnect 31 possible PHY port
locations.
nected Port are defined by the UCSPL register. If a bit
location in the UCSPL register is set, then that sub-port is
connected.
In Figure 11, the registers are set as follows: UCPL3 =
UCPL2 = UCPL1 = 0xF, UCPL0 = 0xFD, and UCSPL = 0xEF.
With bit 1 of UCPL0 cleared, then Port 1 is not connected.
This means that none of the eight sub-ports of Port 1 are
connected. So Port 1 Sub-port 7, Port 1 Sub-port 6, Port 1
Sub-port 5, Port 1 Sub-port 4, Port 1 Sub-port 3, Port 1
20031610
FIGURE 11. Connected Port and Connected Sub-Port Usage
With link-list buffers, each queue may be over-assigned
memory space, working on the assumption that not every
queue will back up simultaneously. To accommodate the rare
occasions where the buffer as a whole approaches full but
individual queues are below their full threshold, the device
also compares the overall buffer fill against a threshold.
Should the overall buffer approach overflow, the flow control
mechanism provides a global ‘halt’ command to ensure that
no cells will be lost.
The MTB Queue Threshold, MTBQT30–MTBQT0 registers
define the maximum size in PDU cells of each of the 31
queues. If all 31 queues are being used it is recommended
that the threshold be left at the default of 4 cells. If less than
31 queues are in use then the queue thresholds may be
raised if required. The recommended maximum queue
thresholds are given in Table 12. These are recommended
maximum thresholds only.
9.0 MTB Queue Configuration
9.1 SINGLE BRIDGE MTB CONFIGURATION
The Multi-port Traffic Buffer is a 160 cell linked-list buffer that
is shared across as many as 31 Port queues. There is a
single queue per MPHY address.
In the up-bridge direction, a per queue flow control protocol
(described in Section 6.3.5 Flow Control) prevents queue
overflow. Each Port has a programmable upper fill threshold.
Should any queue reach this upper threshold, back-pressure
is applied over the serial link, via the flow control mechanism, to the far end (transmitting) device. The transmitting
device uses the normal UTOPIA flow control handshaking to
prevent any more cells being transferred to that MPHY and
thus prevents overflow.
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18
PIA interface of the far end device from accepting cells for
that MPHY address by either, not asserting the CLAV for that
MPHY address when in PHY Mode, or not selecting that
MPHY address when in ATM mode.
(Continued)
It is further recommended that any queue that is not being
used is set with a threshold of zero. When a queue has
reached its programmed threshold the device flow control
mechanism will prevent the far end device from accepting
cells for that MPHY address. Therefore, by setting the
threshold of an unused queue to zero, it prevents the UTO-
Also, note that setting a threshold of zero will cause the
corresponding Queue Full bit in the MTBQFL3–MTBQFL0
registers to be continuously set for that queue.
TABLE 12. Recommended Maximum MTB Queue Thresholds
Number of
Queues in Use
Recommended
Threshold
Number of
Queues in Use
Recommended
Threshold
31
4
15
15
30
4
14
16
29
5
13
18
28
5
12
20
27
5
11
23
26
6
10
26
25
6
9
29
24
7
8
34
23
7
7
39
22
8
6
47
21
9
5
58
20
10
4
74
19
10
3
100
18
11
2
100
17
12
1
154
16
4
9.2 MULTIPLE BRIDGE MTB CONFIGURATION
When UTOPIA-LVDS bridges are used in parallel as in Figure 5 the PHY mode DS92UT16s will forward all cells on the
UTOPIA TxData bus across the LVDS bridge. Cells that are
not addressed for PHYs on a bridge will accumulate in the
MTBs of the ATM mode DS92UT16s. If too many cells
accumulate the MTB will become full and traffic will be
stopped over that bridge. To prevent filling the MTBs PHY
port addresses must be distributed evenly across all bridges
in the system. Additionally, the MTB queue threshold of any
ports not in the Connected Ports List should be set to 0 in
order to limit the number of cells that can accumulate.
Table 13 lists the minimum number of ports that must be
assigned to each bridge for the total number of ports in the
system.
Minimum Number
of Ports per Bridge
31
10
30
9
29
8
28
7
27
6
26
5
25
4
24
3
2
22
1
10.0 Configuration and Traffic
Inhibit Operation
Modifying some device configuration settings should not be
carried out while traffic is flowing. A mechanism to inhibit
traffic is provided, which should be used when changing any
of the settings contained in the PDUCFG, UCFG, USPAL or
USPAM registers.
The Traffic Inhibit mechanism causes traffic to stop. The
UTOPIA interface will stop transmitting and receiving cells,
the LVDS transmit section will transmit Idle cells, and the
incoming cells on the active LVDS receive port will be discarded. It is controlled by the Configuration Traffic Inhibit
(CTI) and Traffic Inhibit Status (TIS) bits of the General
Control and Status (GCS) register, see Section 18.3 GENERAL CONTROL AND STATUS — 0x03 GCS.
The processor should set the CTI bit before changing any of
the PDUCFG, UCFG, USPAL or USPAM register settings.
This will initiate the Traffic Inhibit mechanism. The TIS bit
should then be polled. When the TIS bit is set, then traffic is
inhibited.
The MTB and FIB queues MUST be flushed at this stage.
Use the FIBFL and MTBFL bits of the QFL register described
in Section 18.69 QUEUE FLUSH — 0xD8 QFL to accomplish
the queue flushing. Set these bits to flush the queues and
then poll these bits to determine when flushed. The queue
flushing is complete when these bits are clear.
TABLE 13. Minimum Ports per Bridge in a Mult-Bridge
System
Total Ports Used
23
19
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DS92UT16TUF
9.0 MTB Queue Configuration
DS92UT16TUF
10.0 Configuration and Traffic
Inhibit Operation (Continued)
data can be descrambled and the Frame boundaries found.
Once this has been achieved the received data can be
disassembled.
The device can now be reconfigured safely. When configuration is completed, then the CTI bit can be cleared by the
processor and normal operation resumed.
Note that the CTI bit is set on either power up or software
reset (See Section 18.3 GENERAL CONTROL AND
STATUS — 0x03 GCS) and therefore the Traffic Inhibit
mechanism is active. When initialization of the device registers is completed by the processor the CTI bit should be
cleared.
After achieving TC delineation and the Descrambler locking,
then the cell data within each TC is valid and can be passed
to the MTB. If TC delineation is lost, or the Descrambler is
not locked, then cell data is invalid and is not passed to the
MTB.
Frame delineation must be achieved before the bytes of the
F Channel are considered valid. The F Channel consists of
the ECC, Flow Control, BIP, Remote Alarm and Signalling
and Link Label bytes (Section 6.3.6 F Channel Byte Usage
Within the Frame). If Frame delineation is lost then
• the received ECC bytes are considered invalid and are
assumed to retain the last valid values received
• the Flow Control bytes are considered invalid and are
assumed to be all ones, i.e. ‘halt’ all ports
• the Remote Alarm and Signalling byte is considered invalid and is assumed to retain the last valid value received
• and the Link Label byte is considered invalid and is
assumed to retain the last valid value received.
Note that the devices at both ends of the LVDS link must be
configured with the same values for the PDUCFG, USPAL,
and USPAM registers for correct operation.
Note that when configuration of both ends of the link is
complete then CTI must not be disabled for at least two PDU
transport times (i.e. the length of time it takes to transport
two PDUs over the LVDS link). This “CTI disable hold-off
period” allows all PDUs of the old configuration to be received and discarded correctly. If this hold-off period is not
respected then an idle cell PDU of the old PDU configuration
may arrive at a device programmed with the new PDU
configuration and incorrectly be interpreted as a valid cell.
Note that any change in the PDU configuration which
changes the byte location of the TC HEC byte will cause the
far end device to fall out of TC delineation. See Figure 6.
TC and Frame delineation is achieved using the HEC bytes
of the TC’s. The HEC bytes are not scrambled.
The Descrambler is loaded with the Scrambler sequence on
start-up to achieve lock. The operation of these blocks is
described below.
11.0 Cell/Frame Delineation and
Descrambler Operation
11.1 TRANSPORT CONTAINER DELINEATION
At the receive end of the LVDS link, the data will appear as
a stream with no indication of Transport Container (TC) or
frame boundaries. TC delineation is achieved by finding
correct HEC’s on the incoming data stream. The TC delineation state diagram is shown in Figure 12.
Each of the two Transmission Convergence Sub-Layer
(TCS) DisAssemblers receives 16-bit data from the associated LVDS receive section. The TCS DisAssembler must
first find the Transport Container (TC) boundaries, then the
20031611
FIGURE 12. State Diagram for TC Delineation
C_HUNT — On reset, the TC delineation state machine
starts in the C_HUNT state and TC delineation has not been
achieved. In the C_HUNT state, a HEC is calculated word by
word on a data stream equal in length to the TC Header and
compared against the next received byte. The length of the
TC header is derived from the PDUCFG register (Section
18.5 PDU CONFIGURATION — 0x05 PDUCFG). This prowww.national.com
cess is repeated until a correct HEC is detected. When a
single correct HEC has been detected the state machine
moves into the C_PRESYNC state.
20
PORT A CELL DELINEATION THRESHOLDS — 0x40
RACDT and Section 18.55 RECEIVE PORT B CELL DELINEATION THRESHOLDS — 0x80 RBCDT). On reset, DELTA
= 8 and ALPHA = 7.
Note that depending on the length of the TC and the length
of the TC Header it may be necessary to word slip after a
predefined number of HEC calculations in order to obtain a
correct HEC.
C_PRESYNC — In C_PRESYNC, if a correct HEC is found
DELTA consecutive times then the state machine moves to
the C_SYNC state and the system has achieved TC delineation. If an erred HEC is detected during the C_PRESYNC
state, the process moves back to the C_HUNT state.
11.2 FRAME DELINEATION
Once the system has achieved TC delineation, the Frame
delineation process can begin. The Frame delineation process is achieved by checking for correct HEC’s with the
added coset x6 + x4 + x2 + 1. This added coset differentiates
‘Start of Frame’ TC HEC’s from normal TC HEC’s. Only the
HEC of TC0 has this added coset.
This is the standard coset which may be added to all HEC’s
(CDIS bit in the LKSC register in Section 18.8 LINK STATUS
AND CONTROL — 0x08 LKSC). If the coset is already
added to all HEC’s, then it is added again to the HEC of TC0.
This ensures that the HEC of TC0 can always be differentiated from that of other TC’s.
C_SYNC — In the C_SYNC state, TC delineation is assumed to be lost if an erred HEC is obtained on ALPHA
consecutive occasions. The state machine will move back to
the C_HUNT state.
The values of DELTA and ALPHA are programmable independently for Port A and Port B. They are contained in the
RACDT and RBCDT registers (Section 18.36 RECEIVE
The Frame delineation state diagram is shown in Figure 13.
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FIGURE 13. State Diagram for Frame Delineation
F_HUNT — On reset, the Frame delineation state machine
starts in the F_HUNT state and Frame delineation has not
been achieved. Each received HEC is monitored to determine if it has the added coset and is therefore the Start Of
Frame (SOF) HEC. When a single correct SOF HEC is
detected, the state machine enters the F_PRESYNC state.
F_PRESYNC — In the F_PRESYNC state if a correct SOF
HEC is found SIGMA consecutive times the state machine
moves to the F_SYNC state and the system is said to have
achieved Frame delineation. If an errored SOF HEC is detected during the F_PRESYNC state the state machine
moves back to the F_HUNT state.
F_SYNC — In the F_SYNC state, Frame delineation will be
assumed to be lost if an erred SOF HEC is obtained on MU
consecutive occasions. The state machine will move back to
the F_HUNT state.
The values of SIGMA and MU are programmable independently for Port A and Port B. They are contained in the
RAFDT and RBFDT registers (Section 18.37 RECEIVE
PORT A FRAME DELINEATION THRESHOLDS — 0x41
RAFDT and Section 18.56 RECEIVE PORT B FRAME DELINEATION THRESHOLDS — 0x81 RBFDT). On reset,
SIGMA = 8 and MU = 7.
11.3 DESCRAMBLER OPERATION
Once TC delineation has been obtained, the Descrambler
synchronization can begin.
After reset, the Descrambler expects the far-end transmitting
device to send it’s Scrambler sequence embedded in Idle
cells so that the Descrambler can synchronize (lock) to it.
This scrambler-sequence transfer is achieved by means of
the Remote Descrambler Loss of Lock bit (RDSLL) in the
Remote Alarm and Signalling byte (Section 6.3.7.1 Remote
Alarm and Signaling Byte). This received bit is stored as the
RARDSLL bit of the RARA register for Port A (Section 18.33
RECEIVE
PORT
A
REMOTE
STATUS
AND
ALARMS — 0x3C RARA) and the RBRDSLL bit of the RBRA
register for Port B (Section 18.52 RECEIVE PORT B REMOTE STATUS AND ALARMS — 0x7C RBRA).
The lock status of the Descrambler is transmitted to the
far-end device as the RDSLL bit. If the Descrambler is out of
21
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DS92UT16TUF
11.0 Cell/Frame Delineation and
Descrambler Operation (Continued)
DS92UT16TUF
11.0 Cell/Frame Delineation and
Descrambler Operation (Continued)
scrambler loads this sequence and attempts to lock to it.
Once the Descrambler locks to this sequence, it clears the
RDSLL bit transmitted to the far-end device, which causes
the far-end device to stop sending the Scrambler sequence
embedded in Idle cells and to begin sending real traffic cells.
The Descrambler synchronization state diagram is shown in
Figure 14.
lock, then the transmitted RDSLL = 1. At the far end device,
this is stored as RARDSLL or RBRDSLL, depending on
which port it is connected to. When this bit is set for the
active receive port, it causes the TCS Assembler to transmit
the Scrambler sequence embedded in Idle cells. The De-
20031613
FIGURE 14. State Diagram for Descrambler Synchronization
D_HUNT — On reset, the Descrambler synchronization state
machine starts in the D_HUNT state and the Descrambler is
not in Lock. When TC delineation has been achieved, the
transmitted Scrambler sequence from the far-end device is
loaded into the Descrambler. The state machine enters the
D_PRESYNC state.
D_PRESYNC — The received scrambler sequences and
predicted sequences are compared for each TC. For each
correct prediction, a confidence counter increments, and for
each incorrect prediction, the confidence counter is decremented. When the confidence counter reaches RHO, then
the state machine moves to the D_SYNCH state and the
system is said to have achieved scrambler Lock. If the
confidence counter reaches zero then the state machine
moves back to the HUNT state.
D_SYNC — The comparison of received scrambler sequences and predicted sequences is repeated for each
Frame. For each correct prediction, a confidence counter is
decremented, and for each incorrect prediction, the confidence counter is incremented. The confidence counter has a
lower limit of zero. If the confidence counter reaches PSI,
then the state machine moves back to the D_HUNT state
and the Descrambler is out of Lock.
The state machine will also return directly to D_HUNT if TC
delineation is lost.
The values of PSI and RHO are programmable independently for Port A and Port B. They are contained in the
RADSLKT and RBDSLKT registers (Section 18.38 RECEIVE
PORT
A
DESCRAMBLER
LOCK
THRESHOLDS — 0x42 RADSLKT and Section 18.57 RECEIVE
PORT
B
DESCRAMBLER
LOCK
THRESHOLDS — 0x82 RBDSLKT). On reset PSI = 8 and
RHO = 8.
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11.4 ANALYZING LOCK AND SYNCHRONIZATION TIME
After the DS92UT16 LVDS receiver’s PLL locks onto the
incoming serial data stream and begins to recover data, it
must achieve TC lock, then frame lock and descrambler lock
before transferring cells. The number of cycles to complete
this synchronization depends on the PDU length as well as
the byte location in the TC and frame where the receiver
begins synchronizing.
Here are the assumptions for this example on calculating the
synchronization time.
• PDU length = 64 bytes (maximum possible) = 32 cycles
(16 bit data path)
• Max TC length =PDU + 4 bytes = 34 cycles
• Frame = 56 TC = 1904 cycles
Once the LVDS Receive input PLL locks to the incoming
serial data stream and recovers data bits, the DS92UT16
searches for a TC HEC byte. Assuming that the DS92UT16
just missed a HEC when the LVDS PHY locked, it will take a
minimum of one TC to find the HEC byte. Next, the
DS92UT16 will continue finding correct TC HECs until it
matches the number in the confidence counter (default setting is DELTA = 8). The TC delineation is now in sync.
Next, the UT16 will start looking for SOF HECs that indicate
a start-of-frame. Assuming a SOF has just passed, the max
time to find an SOF should be 1 Frame. Now the UT16 will
collect frames until the correct number matches the confidence counter (default setting is SIGMA = 8). When the
correct number of SOFs matches the confidence counter,
the frame delineation is in sync.
Simultaneous with the frame delineation, the DS92UT16 will
synchronize and lock the descrambler. The lock procedure
begins with the transmitting DS92UT16 sending the scrambler sequence in idle cells. It does this automatically on reset
22
The Serializer outputs remain in TRI-STATE until the PLL
locks to the LVDS_TxClk. After locking to LVDS_TxClk, the
Serializer block is now ready to send data or synchronization
patterns. If the LVDS_Synch pin is high, or the TXSYNC bit
of the LVC register is set (see Section 18.4 LVDS
CONTROL — 0x04 LVC), then the Serializer block generates
and sends the synchronization patterns (sync-pattern).
The internal Port A Deserializer data outputs remain invalid
while the PLL locks to the reference clock.
When the Port A Deserializers PLL locks to incoming data or
sync-pattern on the LVDS_ADin pins, it will clear the corresponding Local Loss Of Signal bit, LLOSA, in the ETXRXA
register (see Section 18.10 ECC TRANSMIT BUFFER AND
RECEIVE LVDS ALARMS — 0x0A ETXRXA) and the lock
pin LVDS_ALock_n will go low.
Step 2: The Deserializer PLL must synchronize to the Serializer to complete the initialization. The Serializer that is
generating the stream to the Deserializer must send random
(non-repetitive) data patterns or sync-patterns during this
step of the Initialization State. The Deserializer will lock onto
sync-patterns within a specified amount of time. The lock to
random data depends on the data patterns and, therefore,
the lock time is unspecified.
In order to lock to the incoming LVDS data stream, the
Deserializer identifies the rising clock edge in a sync-pattern
and will synchronize to the embedded clock in less than 5 µs.
If the Deserializer is locking to a random data stream from
the Serializer, then it performs a series of operations to
identify the rising clock edge and locks to it. Because this
locking procedure depends on the data pattern, it is not
possible to specify how long it will take. At the point where
the Port A Deserializer’s PLL locks to the embedded clock,
the LVDS_ALock_n pin goes low, the LLOSA bit of the
ETXRXA register may be cleared and valid data is presented
to the TCS DisAssembler block. Note that the
LVDS_ALock_n signal is synchronous to valid data being
presented to the TCS DisAssembler.
The user’s application determines whether sync-patterns or
lock to random data is the preferred method for synchronization. If sync-patterns are preferred, the associated Port A
deserializer’s LVDS_ALock_n pin is a convenient way to
provide control of the LVDS_Synch pin, possibly via the
RARLOSA (Receive Port A, Remote Loss Of Signal) bit of
the RARA register, see Section 18.33 RECEIVE PORT A
REMOTE STATUS AND ALARMS — 0x3C RARA.
or start-up until it receives the cleared RDSLL bit in the
Remote Alarm and Signaling byte. After TC delineation occurs at the receive end, the DS92UT16 will count correct
scrambler sequence predictions until it matches the confidence counter (default setting is RHO = 8). When the correct
number of scrambler sequence predictions matches the confidence counter, the descrambler is synchronized and the
receiving DS92UT16 clears the RDSLL bit.
In this example, the time it takes for a receiving DS92UT16
to synchronize to the transmitting DS92UT16, after the PLL
locks, is approximately determined by the following calculation. This time will differ according to PDU length and the
value programmed as the confidence thresholds.
(1+8) TC = 9 (34 cycles) = 306 cycles for TC sync, and (1+8)
(1 frame) = 9 (1904 cycles) = 17136 cycles. This is a total of
17442 cycles and assumes that the descrambler lock occurs
during the 8 frames it takes for the frame delineation to
occur.
12.0 LVDS Interface Operation
The LVDS interface combines a transmit serializer and two
receive deserializers. The serializer accepts 16- bit data from
the TCS Assembler block and transforms it into a serial data
stream with embedded clock information. Each deserializer
recovers the clock and data from the received serial data
stream to deliver the resulting 16-bit wide words to the
corresponding TCS DisAssembler block.
The LVDS interface has a Transmit serializer block and two
Receive deserializer blocks that can operate independent of
each other. The transmit data is duplicated over two differential output pairs with independent tri-state controls. The
transmit block has a power-down control. Each receiver has
a power down control and the two output stages have independent tri-state control. These features enable efficient operation in various applications.
The serializer and deserializer blocks each have three operating states. They are the Initialization, Data Transfer, and
Resynchronization states. In addition, there are two passive
states: Powerdown and TRI-STATE.
The following sections describe each operating mode and
passive state. For clarity these descriptions refer only to the
receive Port A. The operation of receive Port B is the same.
12.2 DATA TRANSFER
After initialization, the Serializer is able to transfer data to the
Deserializer. The serial data stream includes a start bit and
stop bit appended by the serializer, which frame the sixteen
data bits. The start bit is always high and the stop bit is
always low. The start and stop bits also function as clock bits
embedded in the serial stream.
The Serializer block accepts 16-bit data from the TCS Assembler block. The internal version of the LVDS_TxClk signal latches the incoming data. If the LVDS_Synch input or
the TXSYNC bit of the LVC register is high for 5 LVDS_TxClk
cycles, the Serializer does not latch data from the TCS
Assembler block.
The Serializer transmits the data and clock bits (16+2 bits) at
18 times the LVDS_TxClk frequency. For example, if
LVDS_TxClk is 50 MHz, the serial rate is 50 X 18 =
900 Mbps. Since only 16 bits are from input data, the serial
“payload’’ rate is 16 times the LVDS_TxClk frequency. For
12.1 INITIALIZATION
Before the DS92UT16 sends or receives data, it must initialize the links to and from another DS92UT16. Initialization
refers to synchronizing the Serializer’s and the Deserializer’s
PLL’s to local clocks. The local clocks must be the same
frequency or within a specified range if from different
sources. After the Serializers synchronize to the local clocks,
the Deserializers synchronize to the Serializers as the second and final initialization step.
Step 1: After applying VCC and GND to the Serializer and
Deserializer, the LVDS transmit outputs are held in TRISTATE and the on-chip power-sequencing circuitry disables
the internal circuits. When VCC reaches VCCOK (2.2V) in
each device, the PLL in the serializer and deserializer begins
locking to the local clock. In the Serializer, the local clock is
the LVDS_TxClk, while in the Port A Deserializer it is the
reference clock, LVDS_ARefClk. A local on-board oscillator
or other source provides the specified clock input to the
LVDS_TxClk and LVDS_ARefClk pins.
23
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DS92UT16TUF
11.0 Cell/Frame Delineation and
Descrambler Operation (Continued)
DS92UT16TUF
12.0 LVDS Interface Operation
it automatically enters the Initialization state. The system
must then allow time for Initialization before data transfer can
begin.
(Continued)
instance, if LVDS_TxClk = 50 MHz, the payload data rate is
50 X 16 = 800 Mbps. LVDS_TxClk is provided by the data
source and must be in the range of 30 MHz to 52 MHz.
When the Port A Deserializer channel synchronizes to the
input from a Serializer, it drives its LVDS_ALock_n pin low,
the LLOSA bit of the ETXRXA register is cleared and valid
data is delivered to the TCS DisAssembler. The process flow
is that the Port A Deserializer locks to the embedded clock,
uses it to generate multiple internal data strobes, and then
drives the recovered clock on the LVDS_ARxClk pin. The
LVDS_ARxClk is synchronous to the data delivered to the
TCS DisAssembler. While the LVDS_ALock_n pin is low,
data to the TCS DisAssembler is valid. Otherwise, the data is
invalid and is ignored by the TCS DisAssembler and an
interrupt may be raised on the LLOSA bit being set high.
The LVDS_TxPwdn driven low or the TXPWDN bit clear,
forces the Serializer block into low power consumption
where the supply current is in the µA range. The Serializer
PLL stops and the output goes into a TRI-STATE condition.
LVDS_ALock_n and LVDS_ARxClk signals will drive a minimum of three CMOS input gates, a 15 pF total load.
The Port A Deserializer input pins LVDS_ADin are high
impedance during Receiver Powerdown (LVDS_APwdn pin
low or bit RAPWDN of the LVC register set high) and poweroff (VCC = 0V).
12.5 LOOPBACK TEST OPERATION
The DS92UT16 includes two Loopback modes for testing
the device functionality and the transmission line continuity.
They are the Line Loopback and the Local Loopback modes.
The Line Loopback connects the serial data input
(LVDS_ADin or LVDS_BDin) to the serial data output (LVDS_ADout and LVDS_BDout). The input signal also routes to
the parallel data input of the TCS DisAssembler. In the Line
Loopback mode, the serial input stream goes through deserializer, passes to both the DisAssembler and the serializer
inputs, and then is transmitted out onto the transmission line.
The Local Loopback connects the serial data output from the
serializer back to the serial data input of the deserializer. The
connection route includes all the functional blocks of the
DS92UT16 except for the LVDS serial output buffers and
LVDS receiver input.
The ALBC register controls the loopbacks with the LNEN,
LNSEL, LCLA and LCLB bits.
To bring the Serializer block out of the Powerdown state, the
system drives LVDS_TxPwdn high and sets the TXPWDN
bit. When the Serializer exits Powerdown, its PLL must lock
to the LVDS_TxClk before it is ready for the Initialization
state. The system must then allow time for Initialization
before data transfer can begin.
NOTE: The associated reference clock must always be active for a change of state on the receiver powerdowns. That
is LVDS_ARefClk for LVDS_APwdn and LVDS_BRefClk for
LVDS_BPwdn must be active to have an effect.
12.3 RESYNCHRONIZATION
Whenever the Port A Deserializer loses lock, it will automatically try to resynchronize. For example, if the embedded
clock edge is not detected two times in succession, the PLL
loses lock and the LVDS_ALock_n pin and the LLOSA bit are
driven high. The Port A Deserializer then enters the operating mode where it tries to lock to a random data stream. It
looks for the embedded clock edge, identifies it and then
proceeds through the synchronization process.
The logic state of the LVDS_ALock_n pin indicates whether
the data is valid; when it is low, the data is valid. The system
must monitor the LVDS_ALock_n pin and LLOSA bit to
determine whether received data is valid. The DS92UT16
facilitates this by allowing an interrupt to be raised on LLOSA
being set. There is a short delay in response to the PLL
losing synchronization to the incoming data stream.
12.6 LOOP TIMING OPERATION
The DS92UT16 includes a Loop Timing mode controlled by
the LT bit of the GCS register, see Section 18.3 GENERAL
CONTROL AND STATUS — 0x03 GCS. On reset the LT bit is
clear so the LVDS transmit clock is sourced directly from the
LVDS_TxClk pin. Setting the LT bit will switch the transmit
clock to be sourced from the recovered clock of the active
receiver, as defined by the LBA bit of the LKSC register, see
Section 18.8 LINK STATUS AND CONTROL — 0x08 LKSC.
The LVDS transmit and TCA blocks will then be driven by
this internal clock and not the LVDS_TxClk pin.
Switching to or from Loop Timing mode will cause the transmitted scrambler sequence to change. This will cause the far
end device to loose scrambler lock. However, it may take a
number of frames for the far end device to register the lose
of scrambler lock because of the setting of the confidence
counter, see Section 11.3 DESCRAMBLER OPERATION.
The far end device will then relock to the new scrambler
sequence and operation will resume as normal.
Also, when operating in Loop Timing mode, then a Loss of
Lock on the active LVDS receiver, or a switch of active
receiver, will also cause the transmitted scrambler sequence
to change. This again will cause the far end device to loose
scrambler lock. The far end device will then relock to the new
scrambler sequence and operation will resume as normal.
Note that from the time that the near end device is switched
to or from Loop Timing mode, until the time that the far end
device registers the loss of scrambler lock, all received data
The user can choose to resynchronize to the random data
stream or to force fast synchronization by pulsing the Serializer LVDS_Synch pin or setting the TXSYNC bit. This
scheme is left up to the user discretion. One recommendation is to provide a feedback loop using the LVDS_ALock_n
pin itself to control the sync request of the Serializer, which is
the LVDS_Synch pin.
12.4 POWERDOWN/TRI-STATE
The Powerdown state is a very low power consuming sleep
mode that the Serializer and Deserializer will occupy while
waiting for initialization. You can also use the LVDS_ADenb,
LVDS_BDenb,
LVDS_TxPwdn,
LVDS_APwdn
and
LVDS_BPwdn pins, or the TXPWDN, TXADEN, TXBDEN,
RAPWDN and RBPWDN bits of the LVC register to reduce
power when there are no pending data transfers. The Port A
Deserializer enters Powerdown when LVDS_APwdn is
driven low or the RAPWDN bit is set. In Powerdown, the PLL
stops and the outputs go into TRI-STATE, which reduces
supply current to the µA range.
To bring the Port A Deserializer block out of the Powerdown
state, the system drives LVDS_APwdn high and the RAPWDN bit is cleared. When the Deserializer exits Powerdown,
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24
registers (Section 18.28 RECEIVE PORT A HEC
THRESHOLD — 0x31 to 0x33 RAHECT2 to RAHECT0), an
interrupt may be raised on the RAXHEC alarm bit in the
RAPA alarm register (Section 18.31 RECEIVE PORT A PERFORMANCE ALARMS — 0x3A RAPA). The count register
RAHECC2–RAHECC0 is reset on read.
A 24-bit count of errored BIP bytes is similarly maintained in
the RABIPC2–RABIPC0 registers (Section 18.29 RECEIVE
PORT A BIP COUNT — 0x34 to 0x36 RABIPC2 to
RABIPC0). The associated erred BIP threshold is contained
in the RABIPT2–RABIPT0 registers (Section 18.30 RECEIVE PORT A BIP THRESHOLD — 0x36 to 0x39 RABIPT2
to RABIPT0) and an interrupt may be raised on the RAXBIP
alarm bit in the RAPA alarm register. The count register
RABIPC2–RABIPC0 is also reset on read.
(Continued)
at the far end will be corrupted. This is because the scrambler lock works on a frame-by-frame basis and each frame is
56 transport containers long. For this reason switching to or
from Loop Timing mode should not be carried out on live
traffic.
Note that both the input LVDS_TxClk clock and active port
recovered clock must be present for the switch to complete
successfully.
Note also that on reset the device will operate from the
LVDS_TxClk input pin clock and therefore this clock must be
present to ensure correct operation.
The same mechanism is in place for Port B using the
RBHECC2–RBHECC0, RBHECT2–RBHECT0, RBBIPC2–
RBBIPC0, RBBIPT2–RBBIPT0 and RBPA registers (Section
18.46 RECEIVE PORT B HEC COUNT — 0x6E to 0x70
RBHECC2 to RBHECC0, Section 18.47 RECEIVE PORT B
HEC THRESHOLD — 0x71 to 0x73 RBHECT2 to RBHECT0,
Section 18.48 RECEIVE PORT B BIP COUNT — 0x74 to
0x76 RBBIPC2 to RBBIPC0, Section 18.49 RECEIVE PORT
B BIP THRESHOLD — 0x77 to 0x79 RBBIPT2 to RBBIPT0
and Section 18.50 RECEIVE PORT B PERFORMANCE
ALARMS — 0x7A RBPA).
In addition to the HEC and BIP monitoring, live traffic loopback cell monitoring and loopback cell counts are maintained and may raise interrupts on detection of a loopback
cell as described in Section 15.1 ATM CELL LOOPBACK.
13.0 Switching Receive Ports
The DS92UT16 has two independent receive sections designated Port A and Port B. Either port can receive ATM cell
traffic, but only one at a time. The LBA bit of the LKSC
register, described in Section 18.8 LINK STATUS AND
CONTROL — 0x08 LKSC, controls this function.
The ECC also has two independent receive sections. This is
controlled by the settings of the ECCA and ECCB bits of the
LKSC register. Either one or both ECC receive sections can
be active. The selected ECC receive port is independent of
the active traffic port selection. For example, you may select
Port A as active for cell traffic by clearing the LBA bit, and
select the ECC to be receiving on Port B by setting the
ECCB bit. The ECC can communicate over either link without affecting the active cell traffic port because the ECC does
not use any of the transport container designated for ATM
cells.
Selecting the active traffic receive port is accomplished by
simply changing the value of the LBA bit. When set high, Port
B accepts the traffic cells, and when cleared to low, Port A
accepts the traffic cells. After changing the LBA value, the
MTB will complete receiving the current cell before switching
to the new receive Port. The MTB then waits for the next
Start of Cell indication from the associated TCS DisAssembler. This means that the MTB does not need to be flushed or
reset because of a change in the active traffic receive Port.
14.2 BIT ERROR COUNT MODE
In addition to live traffic performance monitoring, a PRBS
based LVDS link bit error count facility is available. In this
mode, no cells are transmitted and instead the raw scrambler pseudo-random sequence (polynomial x31 + x28 + 1) is
transmitted. The descrambler will lock to this sequence and
then count individual bit errors in the PRBS stream. This bit
error count is maintained in a count register. As there is no
data cell delineation, the frame delineation will be lost. This
is not a live traffic test.
The device will transmit this PRBS data when the TXPRBS
bit of the TERRCTL register is set (Section 18.15 TEST
ERROR CONTROL — 0x16 TERRCTL). When this bit is set,
no cell data is transmitted and the TCS Assembler is paused.
In addition, no cells will be read from the FIB queue.
The receive section of Port A can lock onto this sequence
and maintain the bit error count when the RABEC bit of the
RACTL register is set (Section 18.25 RECEIVE PORT A
CONTROL — 0x24 RACTL). The bit error count is maintained in the RABEC2–RABEC0 registers (Section 18.39
RECEIVE PORT A BIT ERROR COUNT — 0x43 to 0x45
RABEC2 to RABEC0). This counter has no associated
threshold register and will not generate an interrupt. The
counter may be polled (read) at fixed intervals to determine
a Bit Error Rate. This counter is reset on read. The count
value is only valid when both the TXPRBS bit and the
RABEC bit are set.
Port B can operate in the same fashion using the RBBEC bit
of the RBCTL register (Section 18.44 RECEIVE PORT B
CONTROL — 0x64 RBCTL) and the RBBEC2–RBBEC0
registers (Section 18.58 RECEIVE PORT B BIT ERROR
COUNT — 0x83 to 0x85 RBBEC2 to RBBEC0).
Switching from one port to another completes in a maximum
of 6 clock cycles. However, this switch does not start until
after receiving the end of the current cell into the MTB.
Changing the value of the LBA bit to switch ports will clear
the ABSC bit of the LKSC register. When the switch from one
port to the other is completed successfully then the hardware
will set the ABSC bit. The processor can poll this bit to
determine when the switch has been completed.
14.0 Performance Monitoring
14.1 LIVE TRAFFIC PERFORMANCE MONITORING
Performance monitoring is carried out on live traffic in two
ways. One is using the HEC bytes associated with each
cell’s TC. The other is the BIP bytes of the F channel
embedded in the frame structure, as described in Section
6.3.7.4 BIP16.
A 24-bit count of errored HEC’s received on Port A is contained in the RAHECC2–RAHECC0 registers (Section 18.27
RECEIVE PORT A HEC COUNT — 0x2E to 0x30 RAHECC2
to RAHECC0). When the number of received erred HEC’s
exceeds the threshold defined in the RAHECT2–RAHECT0
25
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DS92UT16TUF
12.0 LVDS Interface Operation
DS92UT16TUF
14.0 Performance Monitoring
(Continued)
TABLE 14. Performance Monitoring Alarms
Performance Counter
Associated Alarm
Comments
RAHECC2–RAHECC0
(Section 18.27 RECEIVE PORT A HEC
COUNT — 0x2E to 0x30 RAHECC2 to
RAHECC0)
RAXHEC — Rx Port A Excessive HEC
Errors. (Section 18.31 RECEIVE PORT A
PERFORMANCE ALARMS — 0x3A RAPA)
Rx Port A 24-bit errored HEC
counter. Mission mode Up-Bridge
receive direction HEC monitoring.
RABIPC2–RABIPC0
(Section 18.29 RECEIVE PORT A BIP
COUNT — 0x34 to 0x36 RABIPC2 to
RABIPC0)
RAXBIP — Rx Port A Excessive BIP Errors.
(Section 18.31 RECEIVE PORT A
PERFORMANCE ALARMS — 0x3A RAPA)
Rx Port A 24-bit errored BIP
counter. Mission mode link error
monitoring.
RABEC2–RABEC0
(Section 18.39 RECEIVE PORT A BIT
ERROR COUNT — 0x43 to 0x45
RABEC2 to RABEC0)
None
Rx Port A 24-bit Bit Error
Counter. Non-mission mode BER
counter of PRBS data on LVDS
link.
RBHECC2–RBHECC0
(Section 18.46 RECEIVE PORT B
HEC COUNT — 0x6E to 0x70
RBHECC2 to RBHECC0)
RBXHEC — Rx Port B Excessive HEC
Errors. (Section 18.50 RECEIVE PORT B
PERFORMANCE ALARMS — 0x7A RBPA)
Rx Port B 24-bit errored HEC
counter. Mission mode Up-Bridge
receive direction HEC monitoring.
RBBIPC2–RBBIPC0
(Section 18.48 RECEIVE PORT B BIP
COUNT — 0x74 to 0x76 RBBIPC2 to
RBBIPC0)
RBXBIP — Rx Port B Excessive BIP Errors.
(Section 18.50 RECEIVE PORT B
PERFORMANCE ALARMS — 0x7A RBPA)
Rx Port B 24-bit errored BIP
counter. Mission mode link error
monitoring.
RBBEC2–RBBEC0
(Section 18.58 RECEIVE PORT B BIT
ERROR COUNT — 0x83 to 0x85
RBBEC2 to RBBEC0)
None
Rx Port B 24-bit Bit Error
Counter. Non-mission mode BER
counter of PRBS data on LVDS
link.
RAU2DLBC
(Section 18.35 RECEIVE PORT A
UP2DOWN LOOPBACK CELL
COUNT — 0x3E RAU2DLBC)
U2DLBC — Up-2-Down Loopback Cell Count
Change. Cell(s) received on LVDS interface.
(Section 18.72 UTOPIA AND ATM
ALARMS — 0xE1 UAA)
Rx Port A 8-bit Loopback cell
counter. Mission mode diagnostic
aid.
RBU2DLBC
(Section 18.54 RECEIVE PORT B
UP2DOWN LOOPBACK CELL
COUNT — 0x7E RBU2DLBC)
U2DLBC — Up-2-Down Loopback Cell Count
Change. Cell(s) received on LVDS interface.
(Section 18.72 UTOPIA AND ATM
ALARMS — 0xE1 UAA)
Rx Port B 8-bit Loopback cell
counter. Mission mode diagnostic
aid.
D2ULBCC
(Section 18.71 ATM DOWN2UP
LOOPBACK CELL COUNT — 0xE0
D2ULBCC)
D2ULBC — Down-2-Up Loopback Cell Count
Change. Cell(s) transmitted back out on
UTOPIA interface. (Section 18.72 UTOPIA
AND ATM ALARMS — 0xE1 UAA)
UTOPIA Interface 8-bit Loopback
cell counter. Mission mode
diagnostic aid.
TABLE 15. General Alarms
Alarms
Description
LLOSC (Section 18.10 ECC
TRANSMIT BUFFER AND
RECEIVE LVDS
ALARMS — 0x0A ETXRXA)
Change of Status on LLOSA or LLOSB.
LLOSA (Section 18.10 ECC
TRANSMIT BUFFER AND
RECEIVE LVDS
ALARMS — 0x0A ETXRXA)
Loss of Signal on LVDS receive Port A.
LLOSB (Section 18.10 ECC
TRANSMIT BUFFER AND
RECEIVE LVDS
ALARMS — 0x0A ETXRXA)
Loss of Signal on LVDS receive Port B.
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DS92UT16TUF
14.0 Performance Monitoring
(Continued)
TABLE 15. General Alarms (Continued)
Alarms
Description
ETXBR (Section 18.10 ECC
TRANSMIT BUFFER AND
RECEIVE LVDS
ALARMS — 0x0A ETXRXA)
ECC transmit buffer ready for new message.
RALLC (Section 18.23 RECEIVE
PORT A LOCAL ALARMS
— 0x22 RALA)
Receive Port A. Link Label Change of value.
RALLM (Section 18.23
RECEIVE PORT A LOCAL
ALARMS — 0x22 RALA)
Receive Port A. Link Label Mismatch between expected and received value.
RALCS (Section 18.23
RECEIVE PORT A LOCAL
ALARMS — 0x22 RALA)
Receive Port A. Change of Status on RALDSLL, RALTCLL or RALFLL.
RALDSLL (Section 18.23
RECEIVE PORT A LOCAL
ALARMS — 0x22 RALA)
Receive Port A. Descrambler Loss of Lock.
RALTCLL (Section 18.23
RECEIVE PORT A LOCAL
ALARMS — 0x22 RALA)
Receive Port A. Transport Container delineation Loss of Lock.
RALFLL (Section 18.23
RECEIVE PORT A LOCAL
ALARMS — 0x22 RALA)
Receive Port A. Frame delineation Loss of Lock.
ERABF (Section 18.23
RECEIVE PORT A LOCAL
ALARMS — 0x22 RALA)
Receive Port A. ECC Receive Buffer Full — contains valid new message.
RARCS (Section 18.33
RECEIVE PORT A REMOTE
STATUS AND ALARMS — 0x3C
RARA)
Receive Port A. Remote Change of Status on RARLOSA, RARLOSB, RARBA or
RARDSLL.
RARLOSA (Section 18.33
RECEIVE PORT A REMOTE
STATUS AND ALARMS — 0x3C
RARA)
Receive Port A. Remote Loss of Signal on LVDS receive Port A.
RARLOSB (Section 18.33
RECEIVE PORT A REMOTE
STATUS AND ALARMS — 0x3C
RARA)
Receive Port A. Remote Loss of Signal on LVDS receive Port B.
RARBA (Section 18.33
RECEIVE PORT A REMOTE
STATUS AND ALARMS — 0x3C
RARA)
Receive Port A. Remote Active receive port B or A.
RARDSLL (Section 18.33
RECEIVE PORT A REMOTE
STATUS AND ALARMS — 0x3C
RARA)
Receive Port A. Remote Descrambler Loss of Lock.
RBLLC (Section 18.42 RECEIVE
PORT B LOCAL
ALARMS — 0x62 RBLA)
Receive Port B. Link Label Change of value.
RBLLM (Section 18.42
RECEIVE PORT B LOCAL
ALARMS — 0x62 RBLA)
Receive Port B. Link Label Mismatch between expected and received value.
27
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DS92UT16TUF
14.0 Performance Monitoring
(Continued)
TABLE 15. General Alarms (Continued)
Alarms
Description
RBLCS (Section 18.42
RECEIVE PORT B LOCAL
ALARMS — 0x62 RBLA)
Receive Port B. Change of Status on RBLDSLL, RBLTCLL or RBLFLL.
RBLDSLL (Section 18.42
RECEIVE PORT B LOCAL
ALARMS — 0x62 RBLA)
Receive Port B. Descrambler Loss of Lock.
RBLTCLL (Section 18.42
RECEIVE PORT B LOCAL
ALARMS — 0x62 RBLA)
Receive Port B. Transport Container delineation Loss of Lock.
RBLFLL (Section 18.42
RECEIVE PORT B LOCAL
ALARMS — 0x62 RBLA)
Receive Port B. Frame delineation Loss of Lock.
ERBBF (Section 18.42
RECEIVE PORT B LOCAL
ALARMS — 0x62 RBLA)
Receive Port B. ECC Receive Buffer Full — contains valid new message.
RBRCS (Section 18.52
RECEIVE PORT B REMOTE
STATUS AND ALARMS — 0x7C
RBRA)
Receive Port B. Remote Change of Status on RBRLOSA, RBRLOSB, RBRBA or
RBRDSLL.
RBRLOSA (Section 18.52
RECEIVE PORT B REMOTE
STATUS AND ALARMS — 0x7C
RBRA)
Receive Port B. Remote Loss of Signal on LVDS receive Port A
RBRLOSB (Section 18.52
RECEIVE PORT B REMOTE
STATUS AND ALARMS — 0x7C
RBRA)
Receive Port B. Remote Loss of Signal on LVDS receive Port B.
RBRBA (Section 18.52
RECEIVE PORT B REMOTE
STATUS AND ALARMS — 0x7C
RBRA)
Receive Port B. Remote Active receive port B or A.
RBRDSLL (Section 18.52
RECEIVE PORT B REMOTE
STATUS AND ALARMS — 0x7C
RBRA)
Receive Port B. Remote Descrambler Loss of Lock.
PDULA (Section 18.72 UTOPIA
AND ATM ALARMS — 0xE1
UAA)
PDU Length greater than 64 bytes.
CTFRA (Section 18.72 UTOPIA
AND ATM ALARMS — 0xE1
UAA)
Cell Transfer error on UTOPIA interface.
UPRTY (Section 18.72 UTOPIA
AND ATM ALARMS — 0xE1
UAA)
Parity error detected on UTOPIA interface.
FIBOVA (Section 18.72 UTOPIA
AND ATM ALARMS — 0xE1
UAA)
FIB buffer overflow (down-bridge).
MTBSOVA (Section 18.72
UTOPIA AND ATM
ALARMS — 0xE1 UAA)
MTB Soft overflow. One or more of the 31 MTB queues has exceeded its programmed
threshold (up-bridge).
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28
DS92UT16TUF
14.0 Performance Monitoring
(Continued)
TABLE 15. General Alarms (Continued)
Alarms
MTBHOVA (Section 18.72
UTOPIA AND ATM
ALARMS — 0xE1 UAA)
Description
MTB Hard overflow. The MTB queue has overflowed (up-bridge).
The Down2Up Loopback Cell Count register, the D2ULBCC
in Section 18.71 ATM DOWN2UP LOOPBACK CELL
COUNT — 0xE0 D2ULBCC, maintains a count of the
Down2UP_ATM loopback cells. Whenever this counter increments, the D2ULBC alarm in the UAA register is set. See
Section 18.72 UTOPIA AND ATM ALARMS — 0xE1 UAA.
Note that this counter only increments when the loopback
cell exits the device. So the D2ULBC counter increments on
outgoing loopback cells.
Both Receive Port A and Receive Port B maintain
Up2Down_ATM loopback counts. The registers that maintain these counts are the Receive Port A Up2Down Loopback Cell Count register, RAU2DLBC, and the Receive Port
B Up2Down Loopback Cell Count register, RBU2DLBC. See
Section 18.35 RECEIVE PORT A UP2DOWN LOOPBACK
CELL COUNT — 0x3E RAU2DLBC and Section 18.54 RECEIVE PORT B UP2DOWN LOOPBACK CELL
COUNT — 0x7E RBU2DLBC.
15.0 Loopback Operation
To assist in diagnostic testing, the DS92UT16 provides both
physical interface loopbacks and ATM cell loopbacks as
shown in Figure 7 in Section 6.8 LOOPBACKS. The former
is suitable for designer or commission testing when the
device is not passing live traffic. The latter allows cell trace
testing on live traffic. All loopbacks are programmable via the
microprocessor interface. The LVDS physical loopbacks are
described in Section 12.5 LOOPBACK TEST OPERATION.
15.1 ATM CELL LOOPBACK
The ATM Cell Loopback function provides two separate loopback operations. The Down2Up_ATM loopback detects special loopback cells received on the UTOPIA interface and
transmits them back out over the UTOPIA interface. The
Up2Down_ATM loopback detects special loopback cells received on the LVDS interface and transmits them back out
over the LVDS interface. Figure 7(b) in Section 6.8 LOOPBACKS illustrates both of these operations.
These loopback circuits accommodate one loopback cell at
a time. Therefore, a loopback cell should be sent and received before transmitting another loopback cell.
The ATM and LVDS Loopback Control register ALBC controls the ATM cell loopback functionality. See Section 18.14
GENERAL PURPOSE INPUT OUTPUT — 0x15 GPIO. Bit
D2ULB enables the Down2Up_ATM loopback and bit
U2DLB enables the Up2Down_ATM loopback. It is possible
to enable both loopback operations at the same time.
The special loopback cell format is defined in the ATM Loopback Cell Format registers ALBCF3–ALBCF0. See Section
18.20 ATM LOOPBACK CELL FORMAT — 0x1C to 0x1F
ALBCF3 to ALBCF0. These registers define the contents of
the cell’s four header bytes, which indicate that a received
cell is a loopback cell. Associated with the ALBCF3–ALBCF0
registers are the ATM Loopback Cell Filter registers
ALFLT3–ALFLT0. See Section 18.74 ATM LOOPBACK
CELL FILTER — 0xF7 to 0xFA ALFLT3 to AFLT0. These
registers define the cell header bits that are compared with
the header format declared in the ALBCF3–ALBCF0 registers. It is therefore possible to mask out any bits of the cell
header from comparison.
For Down2Up_ATM loopback on the UTOPIA interface only,
a loopback cell will be sent back out to the MPhy address on
which it was received. So, if a loopback cell was detected
coming into the device on MPhy address 0x01, then it will be
sent back out of the device on the next occasion that a cell
for MPhy address 0x01 is to be sent.
Whenever the counter in the Active receiver (as defined by
the LBA bit of the LKSC, see Section 18.8 LINK STATUS
AND CONTROL — 0x08 LKSC) increments, the U2DLBC
alarm in the UAA register is set. See Section 18.72 UTOPIA
AND ATM ALARMS — 0xE1 UAA. Although each counter
increments whenever it detect an incoming loopback cell,
only increments to the active receiver’s counter can set the
alarm. Note that received loopback cells increment these
counters. So the U2DLBC counter increments on incoming
loopback cells.
Alarms in the UAA register will raise an interrupt if the
appropriate interrupt enables are set in the UAIE register.
See Section 18.73 UTOPIA AND ATM INTERRUPT
ENABLES — 0xE2 UAIE.
Loopback cells are only counted and looped-back in the
appropriate loopback mode. If the loopback mode is not set
then any incoming loopback cells are simply treated as
normal traffic cells and passed by the device. In
Up2Down_ATM loopback mode, only cells from the Active
receiver will be looped-back.
A loopback cell transmission may be initiated by the
DS92UT16 over the LVDS transmit link. The TXLVLB bit in
the ALBC register controls this functionality. Setting the
TXLVLB bit causes a single loopback cell to be transmitted
over the LVDS transmit link. When the DS92UT16 finishes
transmitting the loopback cell, it automatically clears the
TXLVLB bit. So, the processor, on setting the TXLVLB bit,
should poll it to detect that it clears before trying to set it
again to send another loopback cell. The loopback cell transmitted will have a header of the format defined by the
ALBCF3–ALBCF0 registers and an MPhy address as defined by the ALBMP register
For Up2Down_ATM loopback on the LVDS interface, the
MPhy address is embedded in the incoming PDU. Therefore,
the loopback cell is simply transmitted back out.
For Down2Up_ATM loopback, only loopback cells as defined
by the ALBCF3–ALBCF0 and ALFLT3–ALFLT0 registers are
looped-back and all other cells are passed as normal.
For Up2Down_ATM loopback, only loopback cells as defined
by the ALBCF3–ALBCF0 and ALFLT3–ALFLT0 registers are
looped back and all other cells are passed as normal.
29
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DS92UT16TUF
Buffer Full (ERABF) interrupt of the Receive Port A Local
Alarm (RALA) register, and the ECC Receive Port B Buffer
Full (ERBBF) interrupt of the Receive Port B Local Alarm
(RBLA) register respectively. The choice of receiving ECC
messages on Port A or Port B is controlled by the ECCB and
ECCA bits of the Link Status and Control (LKSC) register.
The Remote Alarm and Signalling Byte carries the ECC
signaling bits. The transmitted Remote Alarm and Signalling
Byte carries the ESS signal for both of the local ECC receive
sections, ESSA and ESSB. At the receiver a choice must be
made as to which ESS bit of the received Remote Alarm and
Signalling Byte is valid for the local ECC transmitter. This is
controlled by the RAESS and RBESS bits of the RACTL and
RBCTL registers respectively.
16.0 Embedded Communication
Channel Operation
This section describes the ECC operation. The ECC transmits one 8 byte message per frame over the link under
software control. Flow control ensures that messages are
not overwritten at the receive end.
The message to be transmitted is written to the
ETXD7–EXTD0 transmit buffer registers and the received
messages are stored in the Port A ERAD7–ERAD0 or Port B
ERBD7–ERBD0 receive buffer registers. Software control is
achieved on the transmit side using the ECC Transmit Buffer
Ready (ETXBR) interrupt of the ETXRXA register and the
ECC Transmit Send (ETXSD) register.
There are independent receive sections in Port A and Port B
and these are controlled using the ECC Receive Port A
20031614
FIGURE 15. The Basic Structure Of The ECC
16.1 BASIC ECC PROTOCOL — ONE TRANSMIT AND
ONE RECEIVE
The basic operation of an ECC link is described here using
the transmit section of the device at one end of the LVDS link
and a single receive section (Port A) of the device at the
other end of the link.
The ECC transmitter and receiver communicate via the embedded control signals EVN, ESSA and ESSB in the Remote
Alarm and Signalling byte contained in the F1 byte of TC6.
By default both receive ports will extract the incoming ESSA
bit as the valid ESS to pass to the ECC transmit section. This
assumes that the local ECC transmit section is connected to
the remote device receiver port A. If the local transmitter is
connected to the remote device receiver port B then the
incoming ESSB bit must be selected as the valid ESS to
pass to the local ECC transmit section. The selection of valid
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incoming ESS bit is accomplished using the RAESS and
RBESS bits of the RACTL and RBCTL registers respectively.
Note that only one of the incoming remote ESS bits is valid
on each link as the local transmitter cannot be connected to
both receivers on another DS92UT16 device.
The EVN and ESS bits are interpreted as follows:
EVN - Set = Valid ECC data in F1/F2 bytes of TC13, TC20,
TC41 and TC48.
Clear = Null (not valid) ECC data in F1/F2 bytes of
TC13, TC20, TC41 and TC48.
ESS - Set = Stop sending ECC data as receive buffer is full.
Clear = Send ECC data as receive buffer is ready.
The protocol for transmission of an ECC message is as
follows.
30
At this stage the receive buffer is full and cannot receive any
further messages. The transmit buffer ready ETXBR is still
clear meaning that no new messages can be assembled and
ETXSD is held clear so no new messages can be transmitted. This flow control ensures that no new messages will be
transmitted until the current received message is read. This
situation will remain until the received message is read by
the local processor.
Reset
The transmit buffer ready ETXBR bit is set indicating that the
transmit buffer ETXD7–ETXD0 can be written to and the Tx
Buffer Freeze is clear (inactive).
The transmit buffer send ETXSD bit is clear indicating that
no message is being sent and therefore EVN is clear indicating to the receiver that Null data is being transmitted.
Reading A Message
The setting of the ERABF bit in the receiver raises an
interrupt to the local processor indicating that a valid ECC
message has been received and can be read. The receive
buffer registers ERAD7–ERAD0 are read only. The processor may read theses registers in any order and the reading of
them has no affect on the ERABF bit or the ESS signal.
When the processor is finished reading the message from
the buffer it writes to the ERABF bit to clear it. This allows the
receiver to receive a new message. The clearing of the
ERABF bit clears the ESS signals indicating to the transmitter that it can send another message.
The receive buffer full ERABF bit is clear indicating that no
message has been received and therefore ESS is clear
indicating to the transmitter that it can send a message when
ready.
Assembling A Message
As the ETXBR bit is set the processor now has read/write
access to the transmit buffer ETXD7–ETXD0 and can assemble a message by writing to these registers in any order.
The message can be read back for checking. Writing to
these registers does not affect the ETXBR and ETXSD bits
or the EVN signal.
Transmitting a New Message
The clearing of the incoming ESS signal causes the transmitter to set the transmit buffer ETXBR bit. This allows write
access to the transmit buffer ETXD7–ETXD0 for the assembly of a new message. It also releases the ETXSD bit from
reset and the processor can now set this bit to send a new
message.
At this transmitter stage, the ETXBR bit is set, the ETXSD bit
is clear, and EVN is clear. At the receiver, the ERABF bit is
clear and the ESS signal is clear. This is the same situation
as after reset and therefore, the same sequence as above
can be followed to transmit a new message.
Note that the transmit buffer registers can be modified or
overwritten to assemble a new message for transmission, or
the existing message can be resent simply by setting the
ETXSD bit again.
SUMMARY
• Tx - If the ETXBR bit is set, then write the message to the
ETXD7–ETXD0 registers.
• Tx - Set the ETXSD bit to send the message. This clears
ETXBR.
• Rx - When full message is received, the ERABF bit is set
and this raises an interrupt.
• Rx - After reading the message, clear the ERABF bit to
allow new message to be received.
• Tx - The clearing of the ERABF bit sets the ETXBR bit,
which allows a new message to be assembled and transmitted.
Flow Charts
The Flow Charts in Figures 16, 17 summarize the control of
the ECC receive and transmit.
Transmitting A Message
To transmit a message the processor simply sets the send
bit ETXSD. This clears the ETXBR bit preventing write access to the transmit buffer so the message being transmitted
cannot be corrupted by writes to the ETXD7–ETXD0 registers until transmission is completed. The setting of the
ETXSD bit also set the EVN signal indicating to the receiver
that Valid data is being transmitted in the F1/F2 bytes of
TC13, TC20, TC41 and TC48.
Note that transmitting a message depends on the incoming
ESS signal. If ESS is clear indicating that a message can be
sent, then the processor can write to the ETXSD bit. However, if ESS is set indicating that a message cannot be sent,
then the ETXSD bit is held in reset and cannot be written to
by the processor to initiate transmission. This provides flow
control from the receiver back to the transmitter.
Receiving A Message
As the receiver ERABF bit is clear the ESS bit is clear
indicating that the receiver can accept a message. The
receiver monitors the incoming EVN signal to determine
when valid data is being transmitted.
On detecting EVN set the receiver uses the TC number to
extract the 8 ECC message bytes from the incoming data
stream. If an errored HEC is detected on any of the ECC
message bytes then the receiver assumes all 8 bytes are
corrupted and will re-extract the entire message on the next
frame. The transmitter will continue to transmit the message
as long as the ESS signal is clear.
When the receiver determines that it has received the entire
message it sets the receive buffer full ERABF bit. This
prevents the receive buffer ERAD7–ERAD0 being updated
by the incoming ECC bytes so that the message cannot be
overwritten. It also raises an interrupt to the local processor
to indicate that a valid ECC message has been received.
The setting of the ERABF bit also sets the ESS signal back
to the transmitter indicating that it should stop transmission.
This clears the ETXSD bit which clears the EVN signal thus
indicating that transmitted ECC data is Null (not valid).
31
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DS92UT16TUF
16.0 Embedded Communication
Channel Operation (Continued)
DS92UT16TUF
16.0 Embedded Communication Channel Operation
(Continued)
20031615
FIGURE 16. ECC Transmit Flow Chart
20031616
FIGURE 17. ECC Receive Flow Chart (Port A)
16.2 ECC OPERATION WITH ACTIVE AND STANDBY
RECEIVERS
The DS92UT16 has two independent receive sections, Port
A and Port B. These each contain an ECC receive section
and the ECC can be configured to receive over Port A or Port
B or over both Port A and Port B together. The ECC receive
port can be selected independent of the traffic receive port.
Therefore, traffic data is received on the active port designated by the LBA bit of the LKSC register but the ECC can
receive on either Port A or Port B as designated by the
ECCA and ECCB bits of the same LKSC register. In a
protected system with an active and standby LVDS link this
can be used to communicate with the standby link while
traffic continues to be received from the active link. Figure 18
shows three DS92UT16 devices with ECC communication
over both links.
ECC Receive on Port A: Device 1 communicating with
Device 2 only.
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Device 1: For the ECC to communicate across Link A only,
the ECCA bit of the LKSC register is set and the ECCB bit is
clear. The incoming valid ESS signal received over Link A,
“RxA valid ESS”, is the only one used by the ECC transmit
section in Tx. The RxA port is programmed to extract the
incoming ESSA bit as the valid ESS, as the Device 1 transmitter is connected to Device 2 receiver Port A. This is
accomplished by clearing the RAESS bit of the RACTL
register.
In this case, when an ECC message is transmitted, the “RxA
valid ESS” signals when the message has been successfully
received by the far-end Device 2. So, ECC communications
only occur over Link A between Device 1 and Device 2.
Device 2: The ECCA bit of the LKSC register is set and the
ECCB bit is clear. The incoming valid ESS signal received
over Link A, “RxA valid ESS”, is the only one used by the
ECC transmit section in Tx. The RxA port is programmed to
extract the incoming ESSA bit as the valid ESS, as the
32
Device 3 transmitter is connected to Device 1 receiver Port
B. This is accomplished by setting the RBESS bit of the
RBCTL register.
Device 2 transmitter is connected to Device 1 receiver Port
A. This is accomplished by clearing the RAESS bit of the
RACTL register.
ECC Receive on Port B: Device 1 communicating with
Device 3 only.
ECC Receive on Port A and Port B: Device 1 communicating with Device 2 and Device 3.
See Figure 18.
Device 1: For the ECC to communicate across both Link A
and Link B, the ECCB and ECCA bits of the LKSC register
are both set. The incoming valid ESS signals received over
Link A “RxA valid ESS” and Link B “RxB valid ESS” are both
used by the ECC transmit section in Tx.
Device 1: For the ECC to communicate across Link B only,
the ECCA bit of the LKSC register is clear and the ECCB bit
is set. The incoming valid ESS signal received over Link B,
“RxB valid ESS”, is the only one used by the ECC transmit
section in Tx. The RxB port is programmed to extract the
incoming ESSB bit as the valid ESS, as the Device 1 transmitter is connected to Device 3 receiver Port B. This is
accomplished by setting the RBESS bit of the RBCTL register.
In this case, when an ECC message is transmitted, the “RxB
valid ESS” signals when the message has been successfully
received by the far-end Device 3. So, ECC communications
only occur over Link B between Device 1 and Device 3.
In this case, when an ECC message is transmitted, both the
“RxA valid ESS” and “RxB valid ESS” signals must be used
to indicate that the message has been successfully received
by both Device 2 and Device 3 before a new message can
be transmitted. So ECC communications occur over both
Link A and Link B.
Device 2 and 3: are configured as above for communicating
with only Device 1.
Note that, when Device 1 wants to transmit a new message
it must wait until both Device 2 and Device 3 indicate that
they have received the last message. When Device 2 wants
to transmit a new message it must only wait until Device 1
indicates that it has received the last message. Similarly for
Device 3 transmitting a new message it must only wait until
Device 1 indicates that it has received the last message
Device 3: The ECCA bit of the LKSC register is clear and the
ECCB bit is set. The incoming valid ESS signal received
over Link B, “RxB valid ESS”, is the only one used by the
ECC transmit section in Tx. The RxB port is programmed to
extract the incoming ESSB bit as the valid ESS, as the
33
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DS92UT16TUF
16.0 Embedded Communication
Channel Operation (Continued)
DS92UT16TUF
16.0 Embedded Communication Channel Operation
(Continued)
20031617
FIGURE 18. ECC Signalling with Active and Standby Links
lows writing to that port’s registers. Receive Port A (RxA) in
Power-down mode inhibits access to registers described
inSection 18.21 RECEIVE PORT A LINK LABEL — 0x20
RALL to Section 18.39 RECEIVE PORT A BIT ERROR
COUNT — 0x43 to 0x45 RABEC2 to RABEC0. Receive Port
B (RxB) in Power-down mode inhibits access to registers
described in Section 18.40 RECEIVE PORT B LINK
LABEL — 0x60 RBLL to Section 18.58 RECEIVE PORT B
BIT ERROR COUNT — 0x83 to 0x85 RBBEC2 to RBBEC0.
The contents of these registers are not lost or altered in
Power-down mode.
Typical processor Read and Write cycles for this device are
shown in Figures 19, 20, 21, 22. The associated timing for
each cycle is given in Tables 16, 17, 18, 19.
17.0 Microprocessor Interface
Operation
The DS92UT16 contains a flexible microprocessor port capable of interfacing to either Intel or Motorola processors. In
addition to an 8-bit address and 8-bit data bus plus the
associated bus protocol control signals, the port includes an
open-drain interrupt signal. This signal may be asserted on
the detection of various alarms within the device and any of
the potential internal sources of this interrupt may be individually inhibited via an interrupt mask.
Powering down a Receive Port inhibits access to the associated registers. This feature saves power when a Receive
Port is not in use. It allows re-reading the last value read
from a register associated with that Receive Port and disal-
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34
DS92UT16TUF
17.0 Microprocessor Interface Operation
(Continued)
20031618
FIGURE 19. Intel Write Cycle
TABLE 16. Intel Write
No.
Parameter
Min
Max
Units
1
Address Setup Time before Chip Select Low
0
ns
2
Chip Select Setup before Write Low
5
ns
3
Write Pulse Width (Notes 6, 7)
6 cycles
4
Data Setup before Write High (Notes 6, 7)
5 cycles
5
Data Hold after Write High
5
ns
6
Chip Select Hold after Write High
5
ns
7
Address Hold after Write High
0
ns
8
Write Recovery Time (Notes 6, 8)
1 cycle
35
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DS92UT16TUF
17.0 Microprocessor Interface Operation
(Continued)
20031619
FIGURE 20. Intel Read Cycle
TABLE 17. Intel Read
No.
Parameter
1
Address Setup Time before Chip Select Low
2
Chip Select Setup before Write Low
3
Read Pulse Width (Notes 6, 7)
4
Read Low to Data Low Impedance
5
Read Low to Valid Data (Notes 6, 7)
Min
Max
Units
0
ns
0
ns
8 cycles
10
ns
7 cycles + 15 ns
6
Read High to Data High Impedance
7
Chip Select Hold after Read High
0
ns
8
Address Hold after Read High
0
ns
9
Read Recovery Time (Notes 6, 8)
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15
1 cycle
36
ns
DS92UT16TUF
17.0 Microprocessor Interface Operation
(Continued)
20031620
FIGURE 21. Motorola Write Cycle
TABLE 18. Motorola Write
No.
Parameter
Min
Max
Units
1
Address Setup Time before Chip Select Low
0
ns
2
Chip Select Setup before Data Strobe Low
0
ns
3
Read/Write Setup before Data Strobe Low
5
ns
4
Data Strobe Pulse Width (Notes 6, 7)
6 cycles
5
Data Setup before Data Strobe High (Notes 6, 7)
5 cycles
6
Data Hold after Data Strobe High
5
ns
7
Read/Write Hold after Data Strobe High
5
ns
8
Chip Select Hold after Data Strobe High
5
ns
9
Address Hold after Data Strobe High
0
ns
10
Data Strobe Recovery Time (Notes 6, 8)
1 cycle
37
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DS92UT16TUF
17.0 Microprocessor Interface Operation
(Continued)
20031621
FIGURE 22. Motorola Read Cycle
TABLE 19. Motorola Read
No.
Parameter
Min
Max
Units
1
Address Setup Time before Chip Select Low
0
ns
2
Chip Select Setup before Data Strobe Low
0
ns
3
Read/Write Setup before Data Strobe Low
5
ns
4
Data Strobe Pulse Width (Notes 6, 7)
5
Data Strobe Low to Data Low Impedance
6
Data Strobe Low to Valid Data (Notes 6, 7)
7
Data Strobe High to Data High Impedance
8
Read/Write Hold after Data Strobe High
5
ns
8 cycles
10
ns
7 cycles + 15 ns
15
ns
9
Chip Select Hold after Data Strobe High
5
ns
10
Address Hold after Data Strobe High
0
ns
11
Data Strobe Recovery Time (Notes 6, 8)
1 cycle
Note 6: “Cycle” must be greater than or equal to the cycle time of the slowest DS92UT16 clock.
Note 7: When an LVDS receiver loses or gains “lock”, the recovered clock may stay high for up to 2.5 cycles. If a processor access is in progress to one of the
registers in either of the recovered clock domains, then a READ will return the value of the last READ access, and a WRITE will not change the value of the target
register. To accommodate this possible gap in the clock, 3 cycles has been added to these timings and they should therefore be regarded as worst case. If access
time needs to be increased and a system is robust enough to accept these possible incorrect accesses then 3 cycles can be removed from these timings.
Note 8: A recovery time of 1 cycle is required between successive processor accesses.
SOFTWARE LOCK
Note that the device has a software lock mechanism implemented for security. This is described in Section 6.5 CPU
www.national.com
INTERFACE and Section 18.1 SOFTWARE LOCK — 0x00
to 0x01 SLK0 to SLK1.
38
This section describes all the software accessible registers in the DS92UT16. A summary of all registers is shown in Table 20.
TABLE 20. Register Map Summary
Address
Software
Lock
Reset
Value
SLK0
0x00
N
0x00
18.1 Software Lock 1
SLK1
0x01
N
0x00
18.1 Software Lock 2
VID
0x02
N
(Note 9)
GCS
0x03
Y
0x05
18.3 General Control and Status
LVC
0x04
Y
0x3B
18.4 LVDS Control
PDUCFG
0x05
Y
0x00
18.5 PDU Configuration
IS
0x06
N
0x00
18.6 Interrupt Source
ISE
0x07
N
0x00
18.7 Interrupt Source Enables
LKSC
0x08
Y
0x34
18.8 Link Status and Control
TXLL
0x09
N
0x00
18.9 Transmit Link Label
ETXRXA
0x0A
N
0x01
18.10 ECC Transmit Buffer and Receive LVDS Alarms
ETXRXIE
0x0B
N
0x00
18.11 ECC Transmit Buffer and Receive LVDS Interrupt Enables
ETXSD
0x0C
N
0x00
18.12 ECC Transmit Buffer Send
ETXD7
0x0D
N
0x00
18.13 ECC Transmit Buffer 7
ETXD6
0x0E
N
0x00
18.13 ECC Transmit Buffer 6
ETXD5
0x0F
N
0x00
18.13 ECC Transmit Buffer 5
ETXD4
0x10
N
0x00
18.13 ECC Transmit Buffer 4
ETXD3
0x11
N
0x00
18.13 ECC Transmit Buffer 3
ETXD2
0x12
N
0x00
18.13 ECC Transmit Buffer 2
ETXD1
0x13
N
0x00
18.13 ECC Transmit Buffer 1
ETXD0
0x14
N
0x00
18.13 ECC Transmit Buffer 0
GPIO
0x15
N
0xF0
18.14 General Purpose Input/Output
Register Name
Section and Description
18.2 Version Identification
TERRCTL
0x16
Y
0x00
18.15 Test Error Control
ERRBIP1
0x17
Y
0x00
18.16 BIP Error Mask 1
ERRBIP0
0x18
Y
0x00
18.16 BIP Error Mask 0
ERRHEC
0x19
Y
0x00
18.17 HEC Error Mask 0
ALBC
0x1A
N
0x00
18.18 ATM and LVDS Loopback Control
ALBMP
0x1B
N
0x00
18.19 ATM Loopback Cell MPhy
ALBCF3
0x1C
N
0x00
18.20 ATM Loopback Cell Format 3
ALBCF2
0x1D
N
0x00
18.20 ATM Loopback Cell Format 2
ALBCF1
0x1E
N
0x00
18.20 ATM Loopback Cell Format 1
ALBCF0
0x1F
N
0x00
18.20 ATM Loopback Cell Format 0
RALL
0x20
N
0x00
18.21 Receive Port A Link Label
RAELL
0x21
N
0x00
18.22 Receive Port A Expected Link Label
RALA
0x22
N
0x00
18.23 Receive Port A Local Alarms
RALIE
0x23
N
0x00
18.24 Receive Port A Local Interrupt Enables
RACTL
0x24
Y
0x01
18.25 Receive Port A Control
Reserved
0x25
ERAD7
0x26
N
0x00
18.26 ECC Receive Buffer A 7
ERAD6
0x27
N
0x00
18.26 ECC Receive Buffer A 6
ERAD5
0x28
N
0x00
18.26 ECC Receive Buffer A 5
ERAD4
0x29
N
0x00
18.26 ECC Receive Buffer A 4
ERAD3
0x2A
N
0x00
18.26 ECC Receive Buffer A 3
ERAD2
0x2B
N
0x00
18.26 ECC Receive Buffer A 2
ERAD1
0x2C
N
0x00
18.26 ECC Receive Buffer A 1
ERAD0
0x2D
N
0x00
18.26 ECC Receive Buffer A 0
39
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
TABLE 20. Register Map Summary (Continued)
Address
Software
Lock
Reset
Value
RAHECC2
0x2E
N
0x00
18.27 Receive Port A HEC Count 2
RAHECC1
0x2F
N
0x00
18.27 Receive Port A HEC Count 1
Register Name
Section and Description
RAHECC0
0x30
N
0x00
18.27 Receive Port A HEC Count 0
RAHECT2
0x31
N
0xFF
18.28 Receive Port A HEC Threshold 2
RAHECT1
0x32
N
0xFF
18.28 Receive Port A HEC Threshold 1
RAHECT0
0x33
N
0xFF
18.28 Receive Port A HEC Threshold 0
RABIPC2
0x34
N
0x00
18.29 Receive Port A BIP Count 2
RABIPC1
0x35
N
0x00
18.29 Receive Port A BIP Count 1
RABIPC0
0x36
N
0x00
18.29 Receive Port A BIP Count 0
RABIPT2
0x37
N
0xFF
18.30 Receive Port A BIP Threshold 2
RABIPT1
0x38
N
0xFF
18.30 Receive Port A BIP Threshold 1
RABIPT0
0x39
N
0xFF
18.30 Receive Port A BIP Threshold 0
RAPA
0x3A
N
0x00
18.31 Receive Port A Performance Alarms
RAPIE
0x3B
N
0x00
18.32 Receive Port A Performance Interrupt Enables
RARA
0x3C
N
0x0D
18.33 Receive Port A Remote Alarms
RARIE
0x3D
N
0x00
18.34 Receive Port A Remote Interrupt Enables
RAU2DLBC
0x3E
N
0x00
18.35 Receive Port A ATM Up2Down Loopback Cell Count
Unused
0x3F
RACDT
0x40
Y
0x78
18.36 Receive Port A Cell Delineation Thresholds
RAFDT
0x41
Y
0x78
18.37 Receive Port A Frame Delineation Thresholds
RADSLKT
0x42
Y
0x88
18.38 Receive Port a Descrambler Lock Thresholds
RABEC2
0x43
N
0x00
18.38 Receive Port A Bit Error Count 2
RABEC1
0x44
N
0x00
18.38 Receive Port A Bit Error Count 1
RABEC0
0x45
N
0x00
18.38 Receive Port A Bit Error Count 0
Unused
0x46
Reserved
0x47
Reserved
0x48
Unused
0x49 to
0x56
Resered
0x57
Reserved
0x58
Reserved
0x59
Reserved
0x5A
Unused
0x5B
Reserved
0x5C
Reserved
0x5D
Reserved
0x5E
Reserved
0x5F
RBLL
0x60
N
0x00
18.40 Receive Port B Link Label
RBELL
0x61
N
0x00
18.41 Receive Port B Expected Link Label
RBLA
0x62
N
0x00
18.42 Receive Port B Local Alarms
RBLIE
0x63
N
0x00
18.43 Receive Port B Local Interrupt Enables
RBCTL
0x64
Y
0x01
18.44 Receive Port B Control
Reserved
0x65
ERBD7
0x66
N
0x00
18.45 ECC Receive Buffer B 7
ERBD6
0x67
N
0x00
18.45 ECC Receive Buffer B 6
ERBD5
0x68
N
0x00
18.45 ECC Receive Buffer B 5
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40
DS92UT16TUF
18.0 Register Description
(Continued)
TABLE 20. Register Map Summary (Continued)
Address
Software
Lock
Reset
Value
ERBD4
0x69
N
0x00
18.45 ECC Receive Buffer B 4
ERBD3
0x6A
N
0x00
18.45 ECC Receive Buffer B 3
Register Name
Section and Description
ERBD2
0x6B
N
0x00
18.45 ECC Receive Buffer B 2
ERBD1
0x6C
N
0x00
18.45 ECC Receive Buffer B 1
ERBD0
0x6D
N
0x00
18.45 ECC Receive Buffer B 0
RBHECC2
0x6E
N
0x00
18.46 Receive Port B HEC Count 2
RBHECC1
0x6F
N
0x00
18.46 Receive Port B HEC Count 1
RBHECC0
0x70
N
0x00
18.46 Receive Port B HEC Count 0
RBHECT2
0x71
N
0xFF
18.47 Receive Port B HEC Threshold 2
RBHECT1
0x72
N
0xFF
18.47 Receive Port B HEC Threshold 1
RBHECT0
0x73
N
0xFF
18.47 Receive Port B HEC Threshold 0
RBBIPC2
0x74
N
0x00
18.48 Receive Port B BIP Count 2
RBBIPC1
0x75
N
0x00
18.48 Receive Port B BIP Count 1
RBBIPC0
0x76
N
0x00
18.48 Receive Port B BIP Count 0
RBBIPT2
0x77
N
0xFF
18.49 Receive Port B BIP Threshold 2
RBBIPT1
0x78
N
0xFF
18.49 Receive Port B BIP Threshold 1
RBBIPT0
0x79
N
0xFF
18.49 Receive Port B BIP Threshold 0
RBPA
0x7A
N
0x00
18.50 Receive Port B Performance Alarms
RBPIE
0x7B
N
0x00
18.51 Receive Port B Performance Interrupt Enables
RBRA
0x7C
N
0x0D
18.52 Receive Port B Remote Alarms
RBRIE
0x7D
N
0x00
18.53 Receive Port B Remote Interrupt Enables
RBU2DLBC
0x7E
N
0x00
18.54 Receive Port B ATM Up2Down Loopback Cell Count
Unused
0x7F
RBCDT
0x80
Y
0x78
18.55 Receive Port B Cell Delineation Thresholds
RBFDT
0x81
Y
0x78
18.56 Receive Port B Frame Delineation Thresholds
RBDSLKT
0x82
Y
0x88
18.57 Receive Port B Descrambler Lock Thresholds
RBBEC2
0x83
N
0x00
18.58 Receive Port Bit Error Count 2
RBBEC1
0x84
N
0x00
18.58 Receive Port Bit Error Count 1
RBBEC0
0x85
N
0x00
18.58 Receive Port Bit Error Count 0
0x00
18.59 UTOPIA Configuration
Unused
0x86
Reserved
0x87
Reserved
Unused
0x88
0x89 to
0x96
Reserved
0x97
Reserved
0x98
Reserved
0x99
Reserved
0x9A
Unused
0x9B
Reserved
0x9C
Reserved
0x9D
Reserved
0x9E
Reserved
0x9F
UCFG
0xA0
Y
UCPL3
0xA1
Y
0x7F
18.60 UTPOIA Connected Port List 3
UCPL2
0xA2
Y
0xFF
18.60 UTPOIA Connected Port List 2
UCPL1
0xA3
Y
0xFF
18.60 UTPOIA Connected Port List 1
41
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DS92UT16TUF
18.0 Register Description
(Continued)
TABLE 20. Register Map Summary (Continued)
Address
Software
Lock
Reset
Value
UCPL0
0xA4
Y
0xFF
18.60 UTPOIA Connected Port List 0
Reserved
0xA5
UCSPL
0xA6
Y
0x01
18.61 UTOPIA Connected Sub-Port List
USPAL
0xA7
Y
0x00
18.62 UTOPIA Sub-Port Address Location
USPAM
0xA8
Y
0x07
18.63 UTOPIA Sub-Port Address Mask
MTBQT30
0xA9
Y
0x04
18.64 MTB Queue Threshold 30
MTBQT29
0xAA
Y
0x04
18.64 MTB Queue Threshold 29
MTBQT28
0xAB
Y
0x04
18.64 MTB Queue Threshold 28
MTBQT27
0xAC
Y
0x04
18.64 MTB Queue Threshold 27
MTBQT26
0xAD
Y
0x04
18.64 MTB Queue Threshold 26
MTBQT25
0xAE
Y
0x04
18.64 MTB Queue Threshold 25
MTBQT24
0xAF
Y
0x04
18.64 MTB Queue Threshold 24
MTBQT23
0xB0
Y
0x04
18.64 MTB Queue Threshold 23
MTBQT22
0xB1
Y
0x04
18.64 MTB Queue Threshold 22
MTBQT21
0xB2
Y
0x04
18.64 MTB Queue Threshold 21
MTBQT20
0xB3
Y
0x04
18.64 MTB Queue Threshold 20
MTBQT19
0xB4
Y
0x04
18.64 MTB Queue Threshold 19
MTBQT18
0xB5
Y
0x04
18.64 MTB Queue Threshold 18
MTBQT17
0xB6
Y
0x04
18.64 MTB Queue Threshold 17
MTBQT16
0xB7
Y
0x04
18.64 MTB Queue Threshold 16
MTBQT15
0xB8
Y
0x04
18.64 MTB Queue Threshold 15
MTBQT14
0xB9
Y
0x04
18.64 MTB Queue Threshold 14
MTBQT13
0xBA
Y
0x04
18.64 MTB Queue Threshold 13
MTBQT12
0xBB
Y
0x04
18.64 MTB Queue Threshold 12
MTBQT11
0xBC
Y
0x04
18.64 MTB Queue Threshold 11
MTBQT10
0xBD
Y
0x04
18.64 MTB Queue Threshold 10
MTBQT9
0xBE
Y
0x04
18.64 MTB Queue Threshold 9
MTBQT8
0xBF
Y
0x04
18.64 MTB Queue Threshold 8
MTBQT7
0xC0
Y
0x04
18.64 MTB Queue Threshold 7
MTBQT6
0xC1
Y
0x04
18.64 MTB Queue Threshold 6
MTBQT5
0xC2
Y
0x04
18.64 MTB Queue Threshold 5
MTBQT4
0xC3
Y
0x04
18.64 MTB Queue Threshold 4
MTBQT3
0xC4
Y
0x04
18.64 MTB Queue Threshold 3
MTBQT2
0xC5
Y
0x04
18.64 MTB Queue Threshold 2
MTBQT1
0xC6
Y
0x04
18.64 MTB Queue Threshold 1
MTBQT0
0xC7
Y
0x04
18.64 MTB Queue Threshold 0
MTBQFL3
0xC8
N
0x00
18.65 MTB Queue Full 3
MTBQFL2
0xC9
N
0x00
18.65 MTB Queue Full 2
MTBQFL1
0xCA
N
0x00
18.65 MTB Queue Full 1
MTBQFL0
0xCB
N
0x00
18.65 MTB Queue Full 0
MTBQE3
0xCC
N
0x7F
18.66 MTB Queue Empty 3
MTBQE2
0xCD
N
0xFF
18.66 MTB Queue Empty 2
MTBQE1
0xCE
N
0xFF
18.66 MTB Queue Empty 1
MTBQE0
0xCF
N
0xFF
18.66 MTB Queue Empty 0
MTBQF3
0xD0
Y
0x00
18.67 MTB Queue Flush 3
MTBQF2
0xD1
Y
0x00
18.67 MTB Queue Flush 2
MTBQF1
0xD2
Y
0x00
18.67 MTB Queue Flush 1
Register Name
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Section and Description
42
DS92UT16TUF
18.0 Register Description
(Continued)
TABLE 20. Register Map Summary (Continued)
Address
Software
Lock
Reset
Value
MTBQF0
0xD3
Y
0x00
18.67 MTB Queue Flush 0
MTBCF3
0xD4
Y
0x00
18.68 MTB Cell Flush 3
MTBCF2
0xD5
Y
0x00
18.68 MTB Cell Flush 2
MTBCF1
0xD6
Y
0x00
18.68 MTB Cell Flush 1
MTBCF0
0xD7
Y
0x00
18.68 MTB Cell Flush 0
Register Name
Section and Description
QFL
0xD8
Y
0x00
18.69 Queue Flush
MTBQOV3
0xD9
N
0x00
18.70 MTB Queue Overflow 3
MTBQOV2
0xDA
N
0x00
18.70 MTB Queue Overflow 2
MTBQOV1
0xDB
N
0x00
18.70 MTB Queue Overflow 1
0xDC
N
0x00
18.70 MTB Queue Overflow 0
MTBQOV0
Unused
0xDD to
0xDF
D2ULBCC
0xE0
N
0x00
18.71 ATM Down2Up Loopback Cell Count
UAA
0xE1
N
0x00
18.72 UTOPIA and ATM Alarms
UAIE
0xE2
N
0x00
18.73 UTOPIA and ATM Interrupt Enables
Unused
0xE3 to
0xF6
ALFLT3
0xF7
N
0xFF
18.74 ATM Loopback Cell Filter 3
ALFLT2
0xF8
N
0xFF
18.74 ATM Loopback Cell Filter 2
ALFLT1
0xF9
N
0xFF
18.74 ATM Loopback Cell Filter 1
ALFLT0
0xFA
N
0xFF
18.74 ATM Loopback Cell Filter 0
Unused
0xFB
Reserved
0xFC
Reserved
0xFD
Reserved
0xFE
Reserved
0xFF
Note 9: The reset value of the VID register will be different for various versions of the device.
Note 10: All configuration and control registers can be read by the processor to determine the status of the DS92UT16.
Note 11: All reserved (register bits for internal use only) and unused (no register) bits will be read as zero and should be written as zero to ensure future
compatibility.
Note 12: Writing to read only register bits has no affect.
18.1 SOFTWARE LOCK — 0x00 to 0x01 SLK0 to SLK1
TABLE 21. SLK0–SLK1
7
6
5
4
3
2
1
0
SLK0 0x00
0
0
0
0
0
0
0
0
SLK1 0x01
0
0
0
0
0
0
0
0
Type: Read as 0x00
Software Lock: No
Reset Value: 0x00
The Software Lock registers are used to implement a software lock mechanism on configuration and control registers to prevent
spurious software changes to the device which may affect its operation. On reset the Software Lock is ON. Writes to registers
protected by this lock will have no affect. To switch the lock OFF the following sequence of writes to the SLK registers must occur.
UNLOCK SEQUENCE
1. Write data 0x00 to SLK0.
2. Write data 0xFF to SLK1.
The software lock is now OFF and those registers protected by it can be successfully written to.
To switch the lock back On the following sequence of writes to the SLK registers must occur.
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DS92UT16TUF
18.0 Register Description
(Continued)
LOCK SEQUENCE
1. Write data 0xDE to SLK0.
2. Write data 0xAD to SLK1.
The software lock is now ON and those registers protected by it cannot be written to.
The order of the writes in each sequence must be followed. However, the sequence does not have to be contiguous. For instance,
the processor can Write data 0xDE to SLK0, then carry out further read/write cycles to this or another device before completing
the LOCK sequence with Write data 0xAD to SLK1.
The full lock or unlock sequence must be completed to take effect.
The status of the Software Lock can be read at any time from the SLOCK bit of the GCS register.
18.2 VERSION IDENTIFICATION — 0x02 VID
TABLE 22. VID
7
6
5
4
3
2
1
0
VID[7]
VID[6]
VID[5]
VID[4]
VID[3]
VID[2]
VID[1]
VID[0]
Type: Read only
Software Lock: No
Reset Value: (Note 9)
• VID[7:0] Version identification number. NOTE that this is only a proprietary Version number and that the standard Device ID
register is contained in the JTAG TAP controller as described in Section 19.0 Test Features.
18.3 GENERAL CONTROL AND STATUS — 0x03 GCS
TABLE 23. GCS
7
6
5
4
3
2
1
0
Reserved
Reserved
GIE
LT
RESET
CTI
TIS
SLOCK
Type:
Bits[5:2] Read/Write
Bit[1:0] Read Only
Software Lock: Yes
Reset Value:
0x05
• GIE The Global Interrupt Enable enables the device interrupt output pin CPU_INT. Set = Interrupts enabled and Clear =
Interrupts disabled.
• LT The Loop Timing bit enables the connection of the Active Rx port recovered clock to the LVDS Transmit clock (the active
Rx port is as defined by the LBA bit of the LKSC register). LT Set = LVDS Tx clock sourced from Active Rx port recovered
clock. LT Clear = LVDS Tx clock sourced from LVDS_TxClk pin.
• RESET Set = Software reset of all registers except this bit. The Software Lock status as refiected by SLOCK is also not
affected by a software reset.
• CTI Configuration Traffic Inhibit. The setting of this bit initiates the Traffic Inhibit functionality, which stops traffic flow. The
UTOPIA interface will stop transmitting and receiving cells, the LVDS transmit section will transmit Idle cells and the incoming
cells on the active LVDS receive port will be discarded. The MTB and FIB queues must also be flushed. This bit should be set
by the processor whenever the device is being fundamentally reconfigured from the default settings, specifically whenever any
of the PDUCFG, UCFG, USPAL or USPAM registers are being changed. The processor should set this bit before changing
any of the above mentioned register settings. This will initiate Traffic Inhibit. The TIS bit should then be polled until set to
confirm that traffic is inhibited. Note that the MTB and FIB queues MUST be flushed at this stage. This is accomplished
with the FIBFL and MTBFL bits of the QFL register described in Section 18.69 QUEUE FLUSH — 0xD8 QFL. The device
can now be safely reconfigured. When the TIS bit is set, then traffic is inhibited and the device can safely be reconfigured.
When configuration is completed, then the CTI bit can be cleared by the processor and normal operation resumed. Note that
CTI is set on reset so the device is in Traffic Inhibit mode. See Section 10.0 Configuration and Traffic Inhibit Operation.
• TIS Traffic Inhibit Status. This bit reflects the status of the Traffic Inhibit functionality. When set then traffic is inhibited as
described for the CTI bit above. When clear then the device operates normally. The setting of the CTI bit will initiate Traffic
Inhibit which sets the TIS bit. Clearing of the CTI bit clears the TIS bit.
• SLOCK This refiects the status of the Software Lock functionality. Set = Software lock ON and Clear = Software Lock OFF.
The processor can use this bit to determine the Software Lock functionality status when writing to lockable registers.
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DS92UT16TUF
18.0 Register Description
(Continued)
18.4 LVDS CONTROL — 0x04 LVC
TABLE 24. LVC
7
6
5
4
3
2
1
0
Reserved
Reserved
TXPWDN
TXBDEN
TXADEN
TXSYNC
RAPWDN
RBPWDN
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x3B
The LVDS control register configures the LVDS serializer/deserializers.
• TXPWDN Transmit section LVDS power down. Set = Power Up and Clear = Power Down. This register value is combined with
the LVDS_TxPwdn pin to generate the internal power down setting for transmit section. If either this register bit or the
LVDS_TxPwdn pin is clear then the transmit LVDS section is powered down.
• TBDEN LVDS B Transmit data output enable. Set = Enable and Clear = Disable. This register value is combined with the
LVDS_BDenb pin to generate the output enable for the LVDS transmit section B. If either this register bit or the LVDS_BDenb
pin is clear then the transmitter B output is disabled.
• TXADEN LVDS A Transmit data output enable. Set = Enable and Clear = Disable. This register value is combined with the
LVDS_ADenb pin to generate the output enable for the LVDS transmit section A. If either this register bit or the LVDS_ADenb
pin is clear then the transmitter A output is disabled.
• TXSYNC Transmit LVDS synchronization pattern. Set = Enable and Clear = Disable. This register value is combined with the
LVDS_Synch pin to generate the SYNCH input to the LVDS transmit section. If either this register bit or the LVDS_Synch pin
is set then SYNCH patterns are output from the LVDS transmit section.
• RAPWDN Receive Port A LVDS power down. Set = Power Up and Clear = Power Down. This register value is combined with
the LVDS_APwdn pin to generate the internal power down setting for receive Port A. If either this register bit or the
LVDS_APwdn pin is clear then the receive Port A LVDS section is powered down.
• RBPWDN Receive Port B LVDS power down. Set = Power Up and Clear = Power Down. This register value is combined with
the LVDS_BPwdn pin to generate the internal power down setting for receive Port B. If either this register bit or the
LVDS_BPwdn pin is clear then the receive Port B LVDS section is powered down.
18.5 PDU CONFIGURATION — 0x05 PDUCFG
TABLE 25. PDUCFG
7
6
5
4
3
2
1
0
Reserved
UP[2]
UP[1]
UP[0]
UDF
UA[2]
UA[1]
UA[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x00
The PDU Configuration register defines the contents and size of the PDU cells. The register does this by defining the size of the
User Prepend, whether or not the UDF is to be transported, and the size of the User Append. The total size of the PDU must be
in the range 52 to 64 bytes. Therefore the total size of the User Prepend, plus UDF and User Append must not exceed 12 bytes.
Further, as the DS92UT16 operates with an internal 16 bit data path the size of the User Prepend and User Append is defined
in words (16 bits/2 bytes). If the UDF is to be transported, then in UTOPIA 16-bit mode UDF1 and UDF2 bytes are transported
and in UTOPIA 8-bit mode the UDF byte is transported.
• UP[2:0] The UP bits define the length of the User Prepend. Range 0 to 6 words.
• UDF The UDF bit when set indicates that the UDF word should be transported. When cleared the UDF word is not transported.
• UA[2:0] The UA bits define the length of the User Append. Range 0 to 6 words.
45
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DS92UT16TUF
18.0 Register Description
(Continued)
18.6 INTERRUPT SOURCE — 0x06 IS
TABLE 26. IS
7
6
5
4
3
2
1
0
UAA
ETXRXA
RBLA
RBPA
RBRA
RALA
RAPA
RARA
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The Interrupt Source register reflects the source of pending interrupts.
• UAA Set = Interrupt pending in the UAA register.
• ETXRXA Set = Interrupt pending in the ETXRXA register.
• RBLA Set = Interrupt pending in the RBLA register.
•
•
•
•
•
RBPA Set = Interrupt pending in the RBPA register.
RBRA Set = Interrupt pending in the RBRA register.
RALA Set = Interrupt pending in the RALA register.
RAPA Set = Interrupt pending in the RAPA register.
RARA Set = Interrupt pending in the RARA register.
18.7 INTERRUPT SOURCE ENABLES — 0x07 ISE
TABLE 27. ISE
7
6
5
4
3
2
1
0
UAAIE
ETXRXAIE
RBLAIE
RBPAIE
RBRAIE
RALAIE
RAPAIE
RARAIE
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
This register contains the interrupt enables for the corresponding alarms in the IS register. Set = interrupt sources enabled and
Clear = interrupt sources disabled.
18.8 LINK STATUS AND CONTROL — 0x08 LKSC
TABLE 28. LKSC
7
6
5
4
3
2
1
0
RDSLKOV
SCDIS
CEN
ECCA
ECCB
ABSC
LBA
FTXSCR
Type:
Bits[7:3] Read/Write
Bit[2] Read Only
Bits[1:0] Read/Write
Software Lock: Yes
Reset Value:
0x34
The Link Status and Control register is the general control for the transmit and receive links.
• RDSLOV Remote Descrambler Lock Override. When clear, this allows the transmitter/assembler to automatically send Idle
cells containing the Scrambler sequence whenever the remote descrambler falls out of lock. This determined by either the
RARDSLK bit or the RBRDSLK bit clear, depending on the Active receive port defined by the LBA bit. This action should force
the remote descrambler back into lock. Traffic cells are not transmitted during this action until remote descrambler lock is
achieved. If the RDSLKOV bit is set then the actual status of the remote descrambler (RARDSLK or RBRDSLK) is ignored and
it is assumed that the remote descrambler is locked and therefore normal traffic cells are transmitted.
• SCDIS Transmit scrambler disable. When set the scrambler is disabled and unscrambled data is transmitted. When clear the
scrambler is active and transmitted data is scrambled.
• CEN Coset enable. When set then the optional coset x6 + x4 + x2 + 1 is added to the generated CRC-8 used for the HEC.
When clear the coset is not added to the HEC.
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46
(Continued)
• ECCA ECC active on Port A bit. When set, this indicates to the ECC transmit section that the ETXBR bit (Section 18.10 ECC
TRANSMIT BUFFER AND RECEIVE LVDS ALARMS — 0x0A ETXRXA) will be set only when the far end ECC receiver
connected to Port A indicates via the ECC signalling (received ESSA or ESSB signal, as selected by bit RAESS of register
RACTL) over Port A that the message has been received successfully. When clear the ECC signalling over Port A will be
ignored as the ECC Port A receiver is disabled and the ERABF bit will be held clear. See Section 16.0 Embedded
Communication Channel Operation.
• ECCB ECC active on Port B bit. When set, this indicates to the ECC transmit section that the ETXBR bit (Section 18.10 ECC
TRANSMIT BUFFER AND RECEIVE LVDS ALARMS — 0x0A ETXRXA) will be set only when the far end ECC receiver
connected to Port B indicates via the ECC signalling (received ESSA or ESSB signal, as selected by bit RBESS of register
RBCTL) over Port B that the message has been received successfully. When clear the ECC signalling over Port B will be
ignored as the ECC Port B receiver is disabled and the ERBBF bit will be held clear. See Section 16.0 Embedded
Communication Channel Operation.
• ECCB and ECCA Note that when both these bits are clear, then the ECC transmitter and both receivers are inactive. The
ETXBR, ETXSD, ERABF and ERBBF bits will be held clear, the ECC signalling is ignored and no messages are transmitted
or received. See Section 16.0 Embedded Communication Channel Operation.
• ECCB and ECCA Note that when both these bits are set, this indicates to the ECC transmit section that the ETXBR bit will
only be set when both far end ECC receivers indicate that the transmitted message has been received successfully (received
ESS signals). See Section 16.0 Embedded Communication Channel Operation.
• ABSC A/B Switch completed. When switching active traffic receive port this bit can be polled by the processor to determine
when the switch has been completed successfully. A change of the LBA bit will clear this bit. The ABSC bit should then be
polled by the processor. The ABSC bit is set by the hardware when the active port switching is completed. This bit relates to
the LBA active traffic switching bit and is not related to the ECC port switching bit ECCA and ECCB. See Section 13.0
Switching Receive Ports.
• LBA Local receive port A or B control. When this bit is set, then Receive Port B is Active and Port A is Standby. When clear,
then Port A is Active and Port B is Standby. This bit defines the active traffic port and does not affect which ECC channel is
active as defined by the ECCA and ECCB bits above. See Section 13.0 Switching Receive Ports.
• FTXSCR Force Transmit Scrambler Sequence. When set this forces the transmission of the scrambler sequence which is
used to lock the descrambler.
18.9 TRANSMIT LINK LABEL — 0x09 TXLL
TABLE 29. TXLL
7
6
5
4
3
2
1
0
TXLL[7]
TXLL[6]
TXLL[5]
TXLL[4]
TXLL[3]
TXLL[2]
TXLL[1]
TXLL[0]
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
The Transmit Link Label register defines the contents of the Link Trace Label byte transmitted in TC6.
• TXLL[7:0] Transmitted Link Trace Label byte contents.
18.10 ECC TRANSMIT BUFFER AND RECEIVE LVDS ALARMS — 0x0A ETXRXA
TABLE 30. ETXRXA
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
LLOSC
LLOSA
LLOSB
ETXBR
Type:
Bits[3:1] Read only/Clear on Read
Bit[0] Read only
Software Lock: No
Reset Value:
0x01
This register contains the status of the ECC transmit buffer and the LOCK signals from the two LVDS receive ports. When set the
LLOSA, LLOSB and LLOSC bits will raise an interrupt if the corresponding interrupt enable bit is set.
• LLOSA Local Loss Of Signal on receive Port A. When set this will also clear all the bits in the Receive Port A Remote Alarms
register.
• LLOSB Local Loss Of Signal on receive Port B. When set this will also clear all the bits in the Receive Port B Remote Alarms
register.
• LLOSC Local Loss Of Signal Change. When set this indicates that there has been a change of value for either LLOSA or
LLOSB.
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
The ETXBR register bit indicates that the ECC transmit section has successfully transmitted the full ECC message consisting of
the 8 data bytes contained in registers ETXD7–ETXD0 and a new message can be assembled and transmitted. This is a read
only bit that the processor must examine before assembling a new ECC message in the ETXD7–ETXD0 data registers.
If this bit is not set then any writes to ETXD7–ETXD0 will have no affect.
On reset the ETXBR will be set indicating a message can be assembled for transmission. The processor assembles a message
in the ETXD7–ETXD0 data registers. To send the message the processor simply sets the ETXSD register bit. This clears the
ETXBR bit which prevents write access to the ETXD7–ETXD0 registers so that the message cannot be overwritten. When the far
end ECC receiver indicates via the ECC signalling that the message has been received successfully, then the near end ECC
transmitter ETXSD bit is cleared and the ETXBR bit is set. The ETXBR bit, when set, may raise a processor interrupt if the
corresponding interrupt enable is set. The processor can therefore detect that a message has been successfully transmitted
either by the interrupt or by polling the ETXBR bit.
Note that the ETXBR bit cannot be cleared on a read of this register but can only be cleared by setting the ETXSD bit of the
ETXSD register.
• ETXBR The ETXBR bit, when set, indicates that the current ECC message has been successfully transmitted and a new
message can be assembled. If this bit is not set, then the current message has not been received at the far end and a new
message cannot be assembled. The ETXBR bit is cleared by the setting of the ETXSD bit. The ETXBR bit is set either by the
far end successfully receiving a message or by the processor clearing the ETXSD bit.
18.11 ECC Tx BUFFER AND Rx LVDS INTERRUPT ENABLES — 0x0B ETXRXIE
TABLE 31. ETXRXIE
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
LLOSCIE
LLOSAIE
LLOSBIE
ETXBRIE
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
This register contains the interrupt enables for the alarms in the ETXRXA register. Set = interrupt enabled and Clear = interrupt
disabled.
18.12 ECC TRANSMIT BUFFER SEND — 0x0C ETXSD
TABLE 32. ETXSD
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
ETXSD
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
The ETXSD register bit controls the transmission of an ECC message.
• ETXSD The setting of the ETXSD bit initiates the transmission of the ECC message in the ETXD0–ETXD7 data registers, but
only if the ETXBR is also set. Once transmission of a message has been initiated in this way, it will proceed until the far end
ECC receiver indicates, via the ECC signalling, that the message has been received successfully. The ETXSD bit will be
cleared and the ETXBR register bit is set automatically when the far end ECC receiver indicates that the message has been
received successfully. To re-send the same message simply set the ETXSD bit again.
• See Section 16.0 Embedded Communication Channel Operation for a complete description of the Embedded Communication
Channel operation.
• The processor can halt transmission of a message by clearing the ETXSD bit which sets the ETXBR bit to enable a new
message to be constructed in the ETXD7–ETXD0 registers.
18.13 ECC TRANSMIT BUFFER — 0x0D to 0x14 ETXD7 to ETXD0
TABLE 33. ETXD7–ETXD0
7
6
5
4
3
2
1
0
ETXD7 0x0D
ETXD7[7]
ETXD7[6]
ETXD7[5]
ETXD7[4]
ETXD7[3]
ETXD7[2]
ETXD7[1]
ETXD7[0]
ETXD6 0x0E
ETXD6[7]
ETXD6[6]
ETXD6[5]
ETXD6[4]
ETXD6[3]
ETXD6[2]
ETXD6[1]
ETXD6[0]
ETXD5 0x0F
ETXD5[7]
ETXD5[6]
ETXD5[5]
ETXD5[4]
ETXD5[3]
ETXD5[2]
ETXD5[1]
ETXD5[0]
ETXD4 0x10
ETXD4[7]
ETXD4[6]
ETXD4[5]
ETXD4[4]
ETXD4[3]
ETXD4[2]
ETXD4[1]
ETXD4[0]
ETXD3 0x11
ETXD3[7]
ETXD3[6]
ETXD3[5]
ETXD3[4]
ETXD3[3]
ETXD3[2]
ETXD3[1]
ETXD3[0]
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48
(Continued)
TABLE 33. ETXD7–ETXD0 (Continued)
7
6
5
4
3
2
1
0
ETXD2 0x12
ETXD2[7]
ETXD2[6]
ETXD2[5]
ETXD2[4]
ETXD2[3]
ETXD2[2]
ETXD2[1]
ETXD2[0]
ETXD1 0x13
ETXD1[7]
ETXD1[6]
ETXD1[5]
ETXD1[4]
ETXD1[3]
ETXD1[2]
ETXD1[1]
ETXD1[0]
ETXD0 0x14
ETXD0[7]
ETXD0[6]
ETXD0[5]
ETXD0[4]
ETXD0[3]
ETXD0[2]
ETXD0[1]
ETXD0[0]
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
The ETXD7, ETXD6, ETXD5, ETXD4, ETXD3, ETXD2, ETXD1 and ETXD0 registers contain the ECC message to be transmitted.
• ETXD7–ETXD0 When the ETXBR bit is set, then these registers have full read/write access to allow flexible assembly of the
ECC message before initiating transmission by setting the ETXSD bit. When the ETXBR is clear during message transmission, these registers are read only so that the message being transmitted cannot be overwritten and corrupted.
18.14 GENERAL PURPOSE INPUT OUTPUT — 0x15 GPIO
TABLE 34. GPIO
7
6
5
4
3
2
1
0
DDR[3]
DDR[2]
DDR[1]
DDR[0]
IO[3]
IO[2]
IO[1]
IO[0]
Type:
Bits [7:4] Read/Write
Bits[3:0] are Read Only when GPIO[3:0] are defined as Inputs, and Read/Write when GPIO[3:0] are defined as
Outputs.
Software Lock: No
Reset Value:
0xF0
The General Purpose Input/Output register controls the four general purpose input/output pins GPIO[3:0].
• DDR[3:0] The Data Direction bits DDR[3:0] define the function of the GPIO[3:0] pins. When a DDR bit is set the corresponding
GPIO pin is an input and when the DDR bit is clear the corresponding GPIO pin is an output.
• IO[3:0] The IO bits reflect the value of the GPIO pins. When defined as an output by the DDR bit, then the IO bit value is driven
out on the corresponding GPIO pin. When defined as an input by the DDR bit, then the IO bit value captures the incoming
value on the corresponding GPIO pin.
18.15 TEST ERROR CONTROL — 0x16 TERRCTL
TABLE 35. TERRCTL
7
6
5
4
3
2
1
0
EBRST[3]
EBRST[2]
EBRST[1]
EBRST[0]
ERFHEC
ERCHEC
ERBIP
TXPRBS
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x00
The Test Error Control register is used to control the transmission of a PRBS pattern for Bit Error Rate testing, or to introduce HEC
and BIP errors so that the Cell Delineation, Frame Delineation, Descrambler Lock and performance monitoring functions can be
tested. This is a test register and should not be used on live traffic. The exact nature of the errored HEC and BIP bytes is
determined by the ERRBIP1, ERRBIP0 and ERRHEC registers.
• EBRST[3:0] The Error Burst bits EBRST[3:0] define the number of consecutive erred HEC’s and/or BIP’s to be generated and
transmitted.
• ERFHEC The Error Frame HEC bit, when set, will cause EBRST consecutive Frame HEC’s to be erred. When this has been
completed the hardware will clear this bit.
• ERCHEC The Error Cell HEC bit, when set, will cause EBRST consecutive Cell HEC’s to be erred. When this has been
completed the hardware will clear this bit.
• ERBIP The Error BIP bit, when set, will cause EBRST consecutive BIP’s to be erred. When this has been completed the
hardware will clear this bit.
• TXPRBS Transmit PRBS pattern. When set, the transmit section sends the raw scrambler pseudo-random sequence
(polynomial x31 + x28 + 1). No data is transmitted. The TCS Assembler will be paused and no cells will be read from the FIB
queue. The far end receiver can lock to this PRBS pattern to count bit errors if the RABEC/RBBEC bit is set in the
RACTL/RBCTL register. This is not a live traffic test.
18.16 ERROR BIP MASK — 0x17 to 0x18 ERRBIP1 to ERRBIP0
49
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
TABLE 36. ERRBIP1–ERRBIP0
7
6
5
4
3
2
1
0
ERRBIP1 0x17
EBIP1[7]
EBIP1[6]
EBIP1[5]
EBIP1[4]
EBIP1[3]
EBIP1[2]
EBIP1[1]
EBIP1[0]
ERRBIP0 0x18
EBIP0[7]
EBIP0[6]
EBIP0[5]
EBIP0[4]
EBIP0[3]
EBIP0[2]
EBIP0[1]
EBIP0[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x00
The Error BIP Mask registers controls how errors are introduced into the BIP bytes when bit ERBIP of the TERRCTL register is
set. If a bit is set in the ERRBIP1 or ERRBIP0 register then the corresponding bit in the transmitted BIP is inverted. ERRBIP1
corresponds to the first transmitted BIP byte and ERRBIP0 corresponds to the second transmitted BIP byte.
18.17 ERROR HEC MASK — 0x19 ERRHEC
TABLE 37. ERRHEC
7
6
5
4
3
2
1
0
EHEC[7]
EHEC[6]
EHEC[5]
EHEC[4]
EHEC[3]
EHEC[2]
EHEC[1]
EHEC[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x00
The Error HEC Mask register controls the introduction of errors into the HEC byte when the ERFHEC and/or ERCHEC bits of the
TERRCTL register are set. If a bit is set in the ERRHEC register, then the corresponding bit in the transmitted HEC is inverted.
18.18 ATM AND LVDS LOOPBACK CONTROL — 0x1A ALBC
TABLE 38. ALBC
7
6
5
4
3
2
1
0
Reserved
LNEN
LNSEL
LCLA
LCLB
TXLVLB
D2ULB
D2DLB
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
The ATM and LVDS Loopback Control register controls the loopback functions of the device.
Note that the LVDS Line and Local Loopbacks should not be on at the same time.
• LNEN LVDS Line Loopback enable. Set = ON and Clear = OFF. When set this enables the loopback of the LVDS receive
section, determined by LNSEL, to the transmitter.
• LNSEL LVDS Line Loopback receive section select. Set = Receive B and Clear = Receive A.
• LCLA LVDS Local Loopback transmit to receive Port A. Set = ON and Clear = OFF.
• LCLB LVDS Local Loopback transmit to receive Port B. Set = ON and Clear = OFF.
• TXLVLB When set, this initiates the transmission of a single loopback cell Down Bridge on the LVDS transmitter. This cell will
be transmitted with the MPhy address defined in the ALBMP register and will have a header format as defined in the
ALBCF3–ALBCF0 registers. When the bit is clear, the cell has been transmitted. The processor sets the bit to initiate the
transmission and then polls this bit to determine when transmission has been completed, at which time the process can be
repeated to transmit another loopback cell. See Section 15.1 ATM CELL LOOPBACK.
• D2ULB When set, this enables the ATM Down2Up loopback circuit. Any incoming cells from the UTOPIA interface which
match the format of ALBCF3–ALBCF0, masked by the ALFLT3–ALFLT0 registers, are not stored in the FIB traffic queue but
transmitted back out over the UTOPIA interface. See Section 15.1 ATM CELL LOOPBACK.
• U2DLB When set, this enables the ATM Up2Down loopback circuit. Any incoming cells from the active LVDS receive port
which match the format of ALBCF3–ALBCF0 registers, masked by the ALFLT3–ALFLT0 registers, are not stored in the MTB
traffic queue but transmitted back out over the LVDS transmitter. Note that although there are two independent receivers, this
loopback is designed to operate on live traffic and so only affects cells from the active receiver as defined by the LBA bit of
the LKSC register. See Section 15.1 ATM CELL LOOPBACK.
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50
DS92UT16TUF
18.0 Register Description
(Continued)
18.19 ATM LOOPBACK MPhy — 0x1B ALBMP
TABLE 39. ALBMP
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
LBMP[4]
LBMP[3]
LBMP[2]
LBMP[1]
LBMP[0]
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
The ATM Loopback MPhy register defines the MPhy address attached to the ATM loopback cell. Setting the TXLVLB bit in the
ALBC register initiates these loopback cells.
• LBMP[4:0] ATM loopback cell five bit MPhy address.
18.20 ATM LOOPBACK CELL FORMAT — 0x1C to 0x1F ALBCF3 to ALBCF0
TABLE 40. ALBCF3–ALBCF0
7
6
5
4
3
2
1
0
ALBCF3[7]
ALBCF3[6]
ALBCF3[5]
ALBCF3[4]
ALBCF3[3]
ALBCF3[2]
ALBCF3[1]
ALBCF3[0]
ALBCF2 0x1D
ALBCF2[7]
ALBCF2[6]
ALBCF2[5]
ALBCF2[4]
ALBCF2[3]
ALBCF2[2]
ALBCF2[1]
ALBCF2[0]
ALBCF1 0x1E
ALBCF1[7]
ALBCF1[6]
ALBCF1[5]
ALBCF1[4]
ALBCF1[3]
ALBCF1[2]
ALBCF1[1]
ALBCF1[0]
ALBCF0 0x1F
ALBCF0[7]
ALBCF0[6]
ALBCF0[5]
ALBCF0[4]
ALBCF0[3]
ALBCF0[2]
ALBCF0[1]
ALBCF0[0]
ALBCF3 0x1C
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
The ALBCF3, ALBCF2, ALBCF1 and ALBCF0 registers define the format of the ATM loopback cell header.
• ALBCF3[7:0] Loopback Cell header byte H1 format.
• ALBCF2[7:0] Loopback Cell header byte H2 format.
• ALBCF1[7:0] Loopback Cell header byte H3 format.
• ALBCF0[7:0] Loopback Cell header byte H4 format.
18.21 RECEIVE PORT A LINK LABEL — 0x20 RALL
TABLE 41. RALL
7
6
5
4
3
2
1
0
RALL[7]
RALL[6]
RALL[5]
RALL[4]
RALL[3]
RALL[2]
RALL[1]
RALL[0]
Type:
Read only
Software Lock: No
Reset Value:
0x00
The Receive Port A Link Label register contains the Link Trace Label byte received in TC6 on receive Port A. Whenever the
received link label changes value, the RALLC alarm bit in the RALA register is set, which will raise an interrupt if the
corresponding interrupt enable bit is set.
• RALL[7:0] Port A Received Link Trace Label byte contents.
18.22 RECEIVE PORT A EXPECTED LINK LABEL — 0x21 RAELL
TABLE 42. RAELL
7
6
5
4
3
2
1
0
RAELL[7]
RAELL[6]
RAELL[5]
RAELL[4]
RAELL[3]
RAELL[2]
RAELL[1]
RAELL[0]
51
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DS92UT16TUF
18.0 Register Description
Type:
(Continued)
Read only
Software Lock: No
Reset Value:
0x00
The Receive Port A Expected Link Label register defines the expected contents of the Link Trace Label byte received in TC6 on
receive Port A. If the actual received value, as stored in the RALL register is not the same as the expected value defined here the
RALLM alarm bit in the RALA register is set, which may raise a processor interrupt if the corresponding interrupt enable is set.
• RAELL[7:0] Port A Expected Received Link Trace Label byte contents.
18.23 RECEIVE PORT A LOCAL ALARMS — 0x22 RALA
TABLE 43. RALA
7
6
5
4
3
2
1
0
Reserved
RALLC
RALLM
RALCS
RALDSLL
RALTCLL
RALFF
ERABF
Type:
Bits[6:1] Read only/Clear on Read
Bit[0] Read/Write
Software Lock: No
Reset Value:
0x00
The Receive Port A Local Alarms register contains information on the status of the Port A disassembler. When set RALLC,
RALLM, RALDSLL, RALTCLL and RALFLL will raise an interrupt if the corresponding interrupt enable bits are set. Also a change
in value on RALDSLL, RALTCLL or RALFLL will set the RALCS bit which will raise an interrupt if the corresponding interrupt
enable bit is set.
• RALLC Receive Port A, Local Link Label Change of Status. Set = Change in RALL register value.
• RALLM Receive Port A, Local Link Label Mismatch. Set = Received link label RALL different than expected link label RAELL.
• RALCS Receive Port A, Local Change of Status. Set = change in value of RALDSLL, RALTCLL or RALFLL bits
• RALDSLL Receive Port A, Local Descrambler Loss of Lock. Set = Out of Lock and Clear = Lock.
• RALLTCLL Receive Port A, Local Transport Container Delineation Loss of Lock. Set = Out of Lock and Clear = Lock.
• RALFLL Receive Port A, Local Frame Delineation Loss of Lock. Set = Out of Lock and Clear = Lock.
The ERABF register bit indicates that the ECC receive section for Port A has successfully received a full ECC message consisting
of the 8 data bytes contained in registers ERAD7–ERAD0, and the message can now be read by the processor.
On reset, the ERABF will be clear indicating no valid message has been received. When a valid message is received and stored
in the ERAD7–ERAD0 data registers, the ERABF bit will be set and will raise an interrupt if the corresponding interrupt enable
bit is set. Therefore, the processor can detect a received message on the interrupt or by polling the ERABF bit. When the
processor has finished reading the message from the ERAD7–ERAD0 data registers and is ready to receive a new message it
simply clears the ERABF bit. When a full message has been successfully received this is communicated to the far-end device via
the ECC signalling.
• ERABF The ERABF bit, when set, indicates that ERAD7–ERAD0 data registers contain a full valid received message. The
data in the ERAD7–ERAD0 data registers cannot be overwritten with a new received message while ERABF is set. When
ERABF is cleared this allows the ERAD7–ERAD0 data registers to be overwritten with a new received message.
18.24 RECEIVE PORT A LOCAL INTERRUPT ENABLES — 0x23 RALIE
TABLE 44. RALIE
7
6
5
4
3
2
1
0
Reserved
RALLCIE
RALLMIE
RALCSIE
RALDSLLIE
RALTCLLIE
RALFLLIE
ERABFIE
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
This register contains the interrupt enables for the alarms in the RALA register. Set = interrupt enabled and Clear = interrupt
disabled.
18.25 RECEIVE PORT A CONTROL — 0x24 RACTL
TABLE 45. RACTL
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7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
RAESS
RABEC
RADFLK
RACDIS
52
Type:
(Continued)
Read/Write
Software Lock: Yes
Reset Value:
0x01
The Receive Port A Control register defines the operation of the Port A TCS DisAssembler section.
• RAESS Receive Port A, Valid Received ESS bit select. Two ESS bits are received in the Remote Alarm and Signaling Byte
as described in Section 6.3.7.1 Remote Alarm and Signaling Byte. Only one of these received bits may be designated as valid.
The valid bit is extracted and passed to the ECC transmit section as the ECC signaling bit (ESS) received on Port A. When
RAESS is set then the Remote Alarm and Signaling Byte bit[1], ESSB, is selected as valid and bit[2], ESSA is ignored. When
RAESS is clear then the Remote Alarm and Signaling Byte bit[2], ESSA, is selected as valid and bit[1], ESSB is ignored. The
names ESSA and ESSB of these bits refers to the remote receiver port from which they originated and are not associated with
the local receivers Port A and Port B. See Section 16.0 Embedded Communication Channel Operation.
• RABEC Receive Port A, Bit Error Count mode. When set the receiver expects to receive the raw scrambler PRBS pattern. See
TXPRBS bit of the TERRCTL register. The descrambler will lock to this sequence and then count individual bit errors in the
PRBS stream. This bit error count will be refiected in the RABEC2–RABEC0 registers. As there is no data cell delineation, the
frame delineation will be lost. This is not a live traffic test.
• RADFLK Receive Port A, Descrambler Force Lock. When set the descrambler will be forced out of lock and will immediately
begin to re-lock. The hardware will clear this bit and the descrambler lock status can be monitored on the RALDSLL bit of the
RALA register, see Section 18.23 RECEIVE PORT A LOCAL ALARMS — 0x22 RALA.
• RACDIS Receive Port A, Cell Discard. When set then cells with an errored HEC are discarded.
18.26 ECC RECEIVE BUFFER A — 0x26 to 0x2D ERAD7 to ERAD0
TABLE 46. ERAD7–ERAD0
7
6
5
4
3
2
1
0
ERAD7 0x26
ERAD7[7]
ERAD7[6]
ERAD7[5]
ERAD7[4]
ERAD7[3]
ERAD7[2]
ERAD7[1]
ERAD7[0]
ERAD6 0x27
ERAD6[7]
ERAD6[6]
ERAD6[5]
ERAD6[4]
ERAD6[3]
ERAD6[2]
ERAD6[1]
ERAD6[0]
ERAD5 0x28
ERAD5[7]
ERAD5[6]
ERAD5[5]
ERAD5[4]
ERAD5[3]
ERAD5[2]
ERAD5[1]
ERAD5[0]
ERAD4 0x29
ERAD4[7]
ERAD4[6]
ERAD4[5]
ERAD4[4]
ERAD4[3]
ERAD4[2]
ERAD4[1]
ERAD4[0]
ERAD3 0x2A
ERAD3[7]
ERAD3[6]
ERAD3[5]
ERAD3[4]
ERAD3[3]
ERAD3[2]
ERAD3[1]
ERAD3[0]
ERAD2 0x2B
ERAD2[7]
ERAD2[6]
ERAD2[5]
ERAD2[4]
ERAD2[3]
ERAD2[2]
ERAD2[1]
ERAD2[0]
ERAD1 0x2C
ERAD1[7]
ERAD1[6]
ERAD1[5]
ERAD1[4]
ERAD1[3]
ERAD1[2]
ERAD1[1]
ERAD1[0]
ERAD0 0x2D
ERAD0[7]
ERAD0[6]
ERAD0[5]
ERAD0[4]
ERAD0[3]
ERAD0[2]
ERAD0[1]
ERAD0[0]
Type:
Read only
Software Lock: No
Reset Value:
0x00
The ERAD7, ERAD6, ERAD5, ERAD4, ERAD3, ERAD2, ERAD1 and ERAD0 registers contain the Port A received ECC
message.
• ERAD7–ERAD0 When the ERABF bit is set then these registers contain a valid received ECC message for Port A and cannot
be overwritten by any incoming messages. When the ERABF bit is clear these registers may not contain a valid message and
should not be interpreted as such.
18.27 RECEIVE PORT A HEC COUNT — 0x2E to 0x30 RAHECC2 to RAHECC0
TABLE 47. RAHECC2–RAHECC0
7
6
5
4
3
2
1
0
RAHECC2
0x2E
RAHECC2[7]
RAHECC2[6]
RAHECC2[5]
RAHECC2[4]
RAHECC2[3]
RAHECC2[2]
RAHECC2[1]
RAHECC2[0]
RAHECC1
0x2F
RAHECC1[7]
RAHECC1[6]
RAHECC1[5]
RAHECC1[4]
RAHECC1[3]
RAHECC1[2]
RAHECC1[1]
RAHECC1[0]
RAHECC0
0x30
RAHECC0[7]
RAHECC0[6]
RAHECC0[5]
RAHECC0[4]
RAHECC0[3]
RAHECC0[2]
RAHECC0[1]
RAHECC0[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The RAHECC2, RAHECC1 and RAHECC0 registers contain the Port A received errored HEC count.
• RAHECC2–RAHECC0 This register must be read in the order of most significant byte RAHECC2 first and least significant
byte RAHECC0 last or the value read will not be valid. This counter will not roll-over from 0xFFFFFF to 0x000000 but will stick
at 0xFFFFFF.
53
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
18.28 RECEIVE PORT A HEC THRESHOLD — 0x31 to 0x33 RAHECT2 to RAHECT0
TABLE 48. RAHECT2–RAHECT0
7
6
5
4
3
2
1
0
RAHECT2
0x31
RAHECT2[7]
RAHECT2[6]
RAHECT2[5]
RAHECT2[4]
RAHECT2[3]
RAHECT2[2]
RAHECT2[1]
RAHECT2[0]
RAHECT1
0x32
RAHECT1[7]
RAHECT1[6]
RAHECT1[5]
RAHECT1[4]
RAHECT1[3]
RAHECT1[2]
RAHECT1[1]
RAHECT1[0]
RAHECT0
0x33
RAHECT0[7]
RAHECT0[6]
RAHECT0[5]
RAHECT0[4]
RAHECT0[3]
RAHECT0[2]
RAHECT0[1]
RAHECT0[0]
Type:
Read/Write
Software Lock: No
Reset Value:
0xFF
The RAHECT2, RAHECT1 and RAHECT0 registers contain the Port A received erred HEC threshold. When the error count
RAHECC equals the threshold RAHECT then the RAXHEC alarm will be set.
These registers should not be set to all zeroes.
• RAHECT2–RAHECT0 Most significant byte RAHECT2 and least significant byte RAHECT0.
18.29 RECEIVE PORT A BIP COUNT — 0x34 to 0x36 RABIPC2 to RABIPC0
TABLE 49. RABIPC2–RABIPC0
7
6
5
4
3
2
1
0
RABIPC2 0x34
RABIPC2[7]
RABIPC2[6]
RABIPC2[5]
RABIPC2[4]
RABIPC2[3]
RABIPC2[2]
RABIPC2[1]
RABIPC2[0]
RABIPC1 0x35
RABIPC1[7]
RABIPC1[6]
RABIPC1[5]
RABIPC1[4]
RABIPC1[3]
RABIPC1[2]
RABIPC1[1]
RABIPC1[0]
RABIPC0 0x36
RABIPC0[7]
RABIPC0[6]
RABIPC0[5]
RABIPC0[4]
RABIPC0[3]
RABIPC0[2]
RABIPC0[1]
RABIPC0[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The RABIPC2, RABIPC1 and RABIPC0 registers contain the Port A received errored BIP count.
• RABIPC2–RABIPC0 This register must be read in the order of most significant byte RABIPC2 first and least significant byte
RABIPC0 last or the value read will not be valid. This counter will not roll-over from 0xFFFFFF to 0x000000 but will stick at
0xFFFFFF.
18.30 RECEIVE PORT A BIP THRESHOLD — 0x36 to 0x39 RABIPT2 to RABIPT0
TABLE 50. RABIPT2–RABIPT0
7
6
5
4
3
2
1
0
RABIPT2 0x37
RABIPT2[7]
RABIPT2[6]
RABIPT2[5]
RABIPT2[4]
RABIPT2[3]
RABIPT2[2]
RABIPT2[1]
RABIPT2[0]
RABIPT1 0x38
RABIPT1[7]
RABIPT1[6]
RABIPT1[5]
RABIPT1[4]
RABIPT1[3]
RABIPT1[2]
RABIPT1[1]
RABIPT1[0]
RABIPT0 0x39
RABIPT0[7]
RABIPT0[6]
RABIPT0[5]
RABIPT0[4]
RABIPT0[3]
RABIPT0[2]
RABIPT0[1]
RABIPT0[0]
Type:
Read/Write
Software Lock: No
Reset Value:
0xFF
The RABIPT2, RABIPT1 and RABIPT0 registers contain the Port A received errored BIP threshold. When the error count RABIPC
equals the threshold RABIPT then the RAXBIP alarm will be set.
These registers should not be set to all zeroes.
• RABIPT2–RABIPT0 Most significant byte RABIPT2 and least significant byte RABIPT0.
18.31 RECEIVE PORT A PERFORMANCE ALARMS — 0x3A RAPA
TABLE 51. RAPA
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
RAXHEC
RAXBIP
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
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54
(Continued)
The Receive Port A Performance Alarms register contains information about the error performance of Port A. When set RAXHEC
and RAXBIP will raise an interrupt if the corresponding interrupt enable bits are set.
• RAXHEC Receive Port A, Excessive HEC Errors. Set = Number of HEC errors counted in RAHECC is equal to or greater than
the threshold set in RAHECT. This bit is set when RAHECC = RAHECT and can only be cleared by a read of this register.
• RAXBIP Receive Port A, Excessive BIP Errors. Set = Number of BIP errors counted in RABIPC is equal to or greater than the
threshold set in RABIPT. This bit is set when RABIPC = RABIPT and can only be cleared by a read of this register.
18.32 RECEIVE PORT A PERFORMANCE INTERRUPT ENABLES — 0x3B RAPIE
TABLE 52. RAPIE
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
RAXHECIE
RAXBIPIE
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
This register contains the interrupt enables for the alarms in the RAPA register. Set = interrupt enabled and Clear = interrupt
disabled.
18.33 RECEIVE PORT A REMOTE STATUS AND ALARMS — 0x3C RARA
TABLE 53. RARA
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
RARCS
RARLOSA
RARLOSB
RARBA
RARDSLL
Type:
Bits[4:2] and [0] Read only/Clear on Read
Bit[1] Read only
Software Lock: No
Reset Value:
0x0D
The Receive Port A Remote Status and Alarms register contains information on the status of the far-end device, which is
connected to Port A. On a local Loss of Signal on Port A, LLOSA alarm, these bits return to their reset values. When set, the
RARLOSA, RARLOSB, RARBA, and RARDSLL bits will raise an interrupt if the corresponding interrupt enable is set. Also, a
change in value on RARLOSA, RARLOSB, RARDSLL or RARBA will set the RARCS bit. When set, the RARCS bit will raise an
interrupt if the corresponding interrupt enable is set.
• RARCS Receive Port A, Remote Change of Status at far end device LVDS receive Ports.
• RARLOSA Receive Port A, Remote Loss Of Signal at far end device LVDS receive Port A.
• RARLOSB Receive Port A, Remote Loss Of Signal at far end device LVDS receive Port B.
• RARBA Receive Port A, Remote far end device active receive Port. Set = Port B active and Clear = Port A active. Note that
this bit, if set, will not clear on a read of this register.
• RARDSLL Receive Port A, Remote far end device active receive port Descrambler Loss of Lock. Set = Out of Lock and Clear
= Lock.
18.34 RECEIVE PORT A REMOTE INTERRUPT ENABLES — 0x3D RARIE
TABLE 54. RARIE
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
RARCSIE
RARLOSAIE
RARLOSBIE
RARBAIE
RARDSLLIE
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
This register contains the interrupt enables for the alarms in the RARA register. Set = interrupt enabled and Clear = interrupt
disabled.
55
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
18.35 RECEIVE PORT A UP2DOWN LOOPBACK CELL COUNT — 0x3E RAU2DLBC
TABLE 55. RAU2DLBC
7
6
5
4
3
2
1
0
RAU2DLBC[7] RAU2DLBC[6] RAU2DLBC[5] RAU2DLBC[4] RAU2DLBC[3] RAU2DLBC[2] RAU2DLBC[1] RAU2DLBC[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The Receive Port A Up2Down Loopback Cell Count register counts the number of incoming loopback cells detected from the Port
A LVDS interface when Up2Down loopback is enabled with the U2DLB bit of the ALBC register, see Section 18.18 ATM AND
LVDS LOOPBACK CONTROL — 0x1A ALBC. Note that this counter is incremented when an incoming loopback cell is received
and that this differs from the functionality of the Down2Up Loopback Cell Count register, see Section 18.71 ATM DOWN2UP
LOOPBACK CELL COUNT — 0xE0 D2ULBCC.
• RAU2DLBC[7:0] Port A Up2Down Loopback Cell Count value. This register will not roll-over from 0x00 to 0xFF but will stick
at 0xFF.
18.36 RECEIVE PORT A CELL DELINEATION THRESHOLDS — 0x40 RACDT
TABLE 56. RACDT
7
6
5
4
3
2
1
0
ALPHA[3]
ALPHA[2]
ALPHA[1]
ALPHA[0]
DELTA[3]
DELTA[2]
DELTA[1]
DELTA[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x78
The Receive Port A Cell and Transport Container Delineation Thresholds register controls the operation of the Port A cell
delineation state machine. The cell delineation lock status is reflected in the RALTCLL bit of the RALA register.
• ALPHA[3:0] When in lock this is the number of consecutive incorrect cell HEC’s required to lose cell delineation lock.
• DELTA[3:0] When out of lock this is the number of consecutive correct cell HEC’s required to gain cell delineation lock.
18.37 RECEIVE PORT A FRAME DELINEATION THRESHOLDS — 0x41 RAFDT
TABLE 57. RAFDT
7
6
5
4
3
2
1
0
MU[3]
MU[2]
MU[1]
MU[0]
SIGMA[3]
SIGMA[2]
SIGMA[1]
SIGMA[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x78
The Receive Port A Frame Delineation Thresholds register controls the operation of the Port A frame delineation state machine.
The frame delineation lock status is refiected in the RALFLL bit of the RALA register.
• MU[3:0] When in lock this is the number of consecutive incorrect cell HEC’s required to lose frame delineation lock.
• SIGMA[3:0] When out of lock this is the number of consecutive correct frame HEC’s required to gain frame delineation lock.
18.38 RECEIVE PORT A DESCRAMBLER LOCK THRESHOLDS — 0x42 RADSLKT
TABLE 58. RADSLKT
7
6
5
4
3
2
1
0
PSI[3]
PSI[2]
PSI[1]
PSI[0]
RHO[3]
RHO[2]
RHO[1]
RHO[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x88
The Receive Port A Descrambler Lock Thresholds register controls the operation of the Port A descrambler lock state machine
confidence counter. The descrambler lock status is reflected in the RALDSLL bit of the RALA register.
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56
(Continued)
• PSI[3:0] When in lock this is the threshold that the descrambler confidence counter must reach to lose descrambler lock.
When in lock the descrambler confidence counter increments on incorrect HEC predictions and decrements on good HEC
predictions.
• RHO[3:0] When out of lock this is the threshold that the descrambler confidence counter must reach to gain descrambler lock.
When out of lock the descrambler confidence counter decrements on incorrect HEC predictions and increments on good HEC
predictions.
18.39 RECEIVE PORT A BIT ERROR COUNT — 0x43 to 0x45 RABEC2 to RABEC0
TABLE 59. RABEC2–RABEC0
7
6
5
4
3
2
1
0
RABEC2 0x43
RABEC2[7]
RABEC2[6]
RABEC2[5]
RABEC2[4]
RABEC2[3]
RABEC2[2]
RABEC2[1]
RABEC2[0]
RABEC1 0x44
RABEC1[7]
RABEC1[6]
RABEC1[5]
RABEC1[4]
RABEC1[3]
RABEC1[2]
RABEC1[1]
RABEC1[0]
RABEC0 0x45
RABEC0[7]
RABEC0[6]
RABEC0[5]
RABEC0[4]
RABEC0[3]
RABEC0[2]
RABEC0[1]
RABEC0[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The RABEC2, RABEC1 and RABEC0 registers contain the Port A received bit error count whenever the RABEC bit of the RACTL
register is set. If the RABEC bit of the RACTL register is clear these registers are cleared.
• RABEC2–RABEC0 This register must be read in the order of most significant byte RABEC2 first and least significant byte
RABEC0 last, or the value read will not be valid. This counter will not roll-over from 0xFFFFFF to 0x000000 but will stick at
0xFFFFFF.
18.40 RECEIVE PORT B LINK LABEL — 0x60 RBLL
TABLE 60. RBLL
7
6
5
4
3
2
1
0
RBLL[7]
RBLL[6]
RBLL[5]
RBLL[4]
RBLL[3]
RBLL[2]
RBLL[1]
RBLL[0]
Type:
Read only
Software Lock: No
Reset Value:
0x00
The Receive Port B Link Label register contains the Link Trace Label byte received in TC6 on receive Port B. Whenever the
received link label changes value, the RBLLC alarm bit in the RBLA register is set, which will raise an interrupt if the
corresponding interrupt enable bit is set.
• RBLL[7:0] Port B Received Link Trace Label byte contents.
18.41 RECEIVE PORT B EXPECTED LINK LABEL — 0x61 RBELL
TABLE 61. RBELL
7
6
5
4
3
2
1
0
RBELL[7]
RBELL[6]
RBELL[5]
RBELL[4]
RBELL[3]
RBELL[2]
RBELL[1]
RBELL[0]
57
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
Type:
(Continued)
Read/Write
Software Lock: No
Reset Value:
0x00
The Receive Port B Expected Link Label register defines the expected contents of the Link Trace Label byte received in TC6 on
receive Port B. If the actual received value, as stored in the RBLL register is not the same as the expected value defined here
the RBLLM alarm bit in the RBLA register is set, which may raise a processor interrupt if the corresponding interrupt enable is set.
• RBELL[7:0] Port B Expected Received Link Trace Label byte contents.
18.42 RECEIVE PORT B LOCAL ALARMS — 0x62 RBLA
TABLE 62. RBLA
7
6
5
4
3
2
1
0
Reserved
RBLLC
RBLLM
RBLCS
RBLDSLL
RBLTCLL
RBLFLL
ERBBF
Type:
Bits[6:1] Read only/Clear on Read
Bit[0] Read/Write
Software Lock: No
Reset Value:
0x00
The Receive Port B Local Alarms register contains information on the status of the Port B disassembler. When set, RBLLC,
RBLLM, RBLDSLL, RBLTCLL, and RBLFLL will raise an interrupt if the corresponding interrupt enable bits are set. Also, a change
in value on RBLDSLL, RBLTCLL and RBLFLL will set the RBLCS bit, which will raise an interrupt if the corresponding interrupt
enable bit is set.
• RBLLC Receive Port B, Local Link Label Change of Status. Set = Change in RBLL register value.
• RBLLM Receive Port B, Local Link Label Mismatch. Set = Received link label RBLL different than expected link label RBELL.
• RBLCS Receive Port B, Local Change of Status. Set = change in value of RBLDSLL, RBLTCLL or RBLFLL bits.
• RBLDSLL Receive Port B, Local Descrambler Loss of Lock. Set = Out of Lock and Clear = Lock.
• RBLTCLL Receive Port B, Local Transport Container Delineation Loss of Lock. Set = Out of Lock and Clear = Lock.
• RBLFLL Receive Port B, Local Frame Delineation Loss of Lock. Set = Out of Lock and Clear = Lock.
The ERBBF register bit indicates that the ECC receive section for Port B has successfully received a full ECC message consisting
of the 8 data bytes contained in registers ERBD7–ERBD0 and a the message can now be read by the processor.
On reset, the ERBBF will be clear indicating no valid message has been received. When a valid message is received and stored
in the ERBD7–ERBD0 data registers, the ERBBF bit will be set and will raise an interrupt if the corresponding interrupt enable
bit is set. Therefore, the processor can detect a received message on the interrupt or by polling the ERBBF bit. When the
processor has finished reading the message from the ERBD7–ERBD0 data registers and is ready to receive a new message, it
simply clears the ERBBF bit. When a full message has been successfully received, this is communicated to the far-end device
via the ECC signalling.
• ERBBF The ERBBF bit, when set, indicates that ERBD7–ERBD0 data registers contain a full valid received message. The
data in the ERBD7–ERBD0 data registers cannot be overwritten with a new received message while ERBBF is set. When
ERBBF is cleared, this allows the ERBD7–ERBD0 data registers to be overwritten with a new received message.
18.43 RECEIVE PORT B LOCAL INTERRUPT ENABLES — 0x63 RBLIE
TABLE 63. RBLIE
7
6
5
4
3
2
1
0
Reserved
RBLLCIE
RBLLMIE
RBLCSIE
RBLSLLIE
RBLTCLLIE
RBLFLLIE
ERBBFIE
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
This register contains the interrupt enables for the alarms in the RBLA register. Set = interrupt enabled and Clear = interrupt
disabled.
18.44 RECEIVE PORT B CONTROL — 0x64 RBCTL
TABLE 64. RBCTL
www.national.com
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
RBESS
RBBEC
RBDFLK
RBCDIS
58
Type:
(Continued)
Read/Write
Software Lock: Yes
Reset Value:
0x01
The Receive Port B Control register defines the operation of the Port B TCS DisAssembler section.
• RBESS Receive Port B, Valid Received ESS bit select. Two ESS bits are received in the Remote Alarm and Signaling Byte
as described in Section 6.3.7.1 Remote Alarm and Signaling Byte. Only one of these received bits may be designated as valid.
The valid bit is extracted and passed to the ECC transmit section as the ECC signaling bit (ESS) received on Port B. When
RBESS is set, then the Remote Alarm and Signaling Byte bit[1], ESSB, is selected as valid and bit[2], ESSA is ignored. When
RBESS is clear then the Remote Alarm and Signaling Byte bit[2], ESSA, is selected as valid and bit[1], ESSB is ignored. The
names ESSA and ESSB of these bits refers to the remote receiver port from which they originated and are not associated with
the local receivers Port A and Port B. See Section 16.0 Embedded Communication Channel Operation.
• RBBEC Receive Port B, Bit Error Count mode. When set the receiver expects to receive the raw scrambler PRBS pattern. See
TXPRBS bit of the TERRCTL register. The descrambler will lock to this sequence and then count individual bit errors in the
PRBS stream. This bit error count will be refiected in the RBBEC2–RBBEC0 registers. As there is no data cell delineation, the
frame delineation will be lost. This is not a live traffic test.
• RBDFLK Receive Port B, Descrambler Force Lock. When set the descrambler will be forced out of lock and will immediately
begin to re-lock. The hardware will clear this bit and the descrambler lock status can be monitored on the RBLDSLL bit of the
RBLA register, see Section 18.42 RECEIVE PORT B LOCAL ALARMS — 0x62 RBLA.
• RBCDIS Receive Port B, Cell Discard. When set then cells with an errored HEC are discarded.
18.45 ECC RECEIVE BUFFER B — 0x66 to 0x6D ERBD7 to ERBD0
TABLE 65. ERBD7–ERBD0
7
6
5
4
3
2
1
0
ERBD7 0x66
ERBD7[7]
ERBD7[6]
ERBD7[5]
ERBD7[4]
ERBD7[3]
ERBD7[2]
ERBD7[1]
ERBD7[0]
ERBD6 0x67
ERBD6[7]
ERBD6[6]
ERBD6[5]
ERBD6[4]
ERBD6[3]
ERBD6[2]
ERBD6[1]
ERBD6[0]
ERBD5 0x68
ERBD5[7]
ERBD5[6]
ERBD5[5]
ERBD5[4]
ERBD5[3]
ERBD5[2]
ERBD5[1]
ERBD5[0]
ERBD4 0x69
ERBD4[7]
ERBD4[6]
ERBD4[5]
ERBD4[4]
ERBD4[3]
ERBD4[2]
ERBD4[1]
ERBD4[0]
ERBD3 0x6A
ERBD3[7]
ERBD3[6]
ERBD3[5]
ERBD3[4]
ERBD3[3]
ERBD3[2]
ERBD3[1]
ERBD3[0]
ERBD2 0x6B
ERBD2[7]
ERBD2[6]
ERBD2[5]
ERBD2[4]
ERBD2[3]
ERBD2[2]
ERBD2[1]
ERBD2[0]
ERBD1 0x6C
ERBD1[7]
ERBD1[6]
ERBD1[5]
ERBD1[4]
ERBD1[3]
ERBD1[2]
ERBD1[1]
ERBD1[0]
ERBD0 0x6D
ERBD0[7]
ERBD0[6]
ERBD0[5]
ERBD0[4]
ERBD0[3]
ERBD0[2]
ERBD0[1]
ERBD0[0]
Type:
Read only
Software Lock: No
Reset Value:
0x00
The ERBD7, ERBD6, ERBD5, ERBD4, ERBD3, ERBD2, ERBD1, and ERBD0 registers contain the Port B received ECC
message.
• ERBD7–ERBD0 When the ERBBF bit is set, then these registers contain a valid received ECC message for Port B and
cannot be overwritten by any incoming messages. When the ERBBF bit is clear, these registers may not contain a valid
message and should not be interpreted as such.
18.46 RECEIVE PORT B HEC COUNT — 0x6E to 0x70 RBHECC2 to RBHECC0
TABLE 66. RBHECC2–RBHECC0
7
6
5
4
3
2
1
0
RBHECC2
0x6E
RBHECC2[7]
RBHECC2[6]
RBHECC2[5]
RBHECC2[4]
RBHECC2[3]
RBHECC2[2]
RBHECC2[1]
RBHECC2[0]
RBHECC1
0x6F
RBHECC1[7]
RBHECC1[6]
RBHECC1[5]
RBHECC1[4]
RBHECC1[3]
RBHECC1[2]
RBHECC1[1]
RBHECC1[0]
RBHECC0
0x70
RBHECC0[7]
RBHECC0[6]
RBHECC0[5]
RBHECC0[4]
RBHECC0[3]
RBHECC0[2]
RBHECC0[1]
RBHECC0[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The RBHECC2, RBHECC1 and RBHECC0 registers contain the Port B received errored HEC count.
• RBHECC2–RBHECC0 This register must be read in the order of most significant byte RBHECC2 first and least significant
byte RBHECC0 or the value read will not be valid. This counter will not roll-over from 0xFFFFFF to 0x000000 but will stick at
0xFFFFFF.
59
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
18.47 RECEIVE PORT B HEC THRESHOLD — 0x71 to 0x73 RBHECT2 to RBHECT0
TABLE 67. RBHECT2–RBHECT0
7
6
5
4
3
2
1
0
RBHECT2
0x71
RBHECT2[7]
RBHECT2[6]
RBHECT2[5]
RBHECT2[4]
RBHECT2[3]
RBHECT2[2]
RBHECT2[1]
RBHECT2[0]
RBHECT1
0x72
RBHECT1[7]
RBHECT1[6]
RBHECT1[5]
RBHECT1[4]
RBHECT1[3]
RBHECT1[2]
RBHECT1[1]
RBHECT1[0]
RBHECT0
0x73
RBHECT0[7]
RBHECT0[6]
RBHECT0[5]
RBHECT0[4]
RBHECT0[3]
RBHECT0[2]
RBHECT0[1]
RBHECT0[0]
Type:
Read/Write
Software Lock: No
Reset Value:
0xFF
The RBHECT2, RBHECT1 and RBHECT0 registers contain the Port B received erred HEC threshold. When the error count
RBHECC equals the threshold RBHECT, then the RBXHEC alarm will be set.
These registers should not be set to all zeroes.
• RBHECT2–RBHECT0 Most significant byte RBHECT2 and least significant byte RBHECT0.
18.48 RECEIVE PORT B BIP COUNT — 0x74 to 0x76 RBBIPC2 to RBBIPC0
TABLE 68. RBBIPC2–RBBIPC0
7
6
5
4
3
2
1
0
RBBIPC2 0x74
RBBIPC2[7]
RBBIPC2[6]
RBBIPC2[5]
RBBIPC2[4]
RBBIPC2[3]
RBBIPC2[2]
RBBIPC2[1]
RBBIPC2[0]
RBBIPC1 0x75
RBBIPC1[7]
RBBIPC1[6]
RBBIPC1[5]
RBBIPC1[4]
RBBIPC1[3]
RBBIPC1[2]
RBBIPC1[1]
RBBIPC1[0]
RBBIPC0 0x76
RBBIPC0[7]
RBBIPC0[6]
RBBIPC0[5]
RBBIPC0[4]
RBBIPC0[3]
RBBIPC0[2]
RBBIPC0[1]
RBBIPC0[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The RBBIPC2, RBBIPC1 and RBBIPC0 registers contain the Port B received errored BIP count.
• RBBIPC2–RBBIPC0 This register must be read in the order of most significant byte RBBIPC2first and least significant byte
RBBIPC0 or the value read will not be valid. This counter will not roll-over from 0xFFFFFF to 0x000000 but will stick at
0xFFFFFF.
18.49 RECEIVE PORT B BIP THRESHOLD — 0x77 to 0x79 RBBIPT2 to RBBIPT0
TABLE 69. RBBIPT2–RBBIPT0
7
6
5
4
3
2
1
0
RBBIPT2 0x77
RBBIPT2[7]
RBBIPT2[6]
RBBIPT2[5]
RBBIPT2[4]
RBBIPT2[3]
RBBIPT2[2]
RBBIPT2[1]
RBBIPT2[0]
RBBIPT1 0x78
RBBIPT1[7]
RBBIPT1[6]
RBBIPT1[5]
RBBIPT1[4]
RBBIPT1[3]
RBBIPT1[2]
RBBIPT1[1]
RBBIPT1[0]
RBBIPT0 0x79
RBBIPT0[7]
RBBIPT0[6]
RBBIPT0[5]
RBBIPT0[4]
RBBIPT0[3]
RBBIPT0[2]
RBBIPT0[1]
RBBIPT0[0]
Type:
Read/Write
Software Lock: No
Reset Value:
0xFF
The RBBIPT2, RBBIPT1 and RBBIPT0 registers contain the Port B received erred BIP threshold. When the error count RBBIPC
equals the threshold RBBIPT, then the RBXBIP alarm will be set.
These registers should not be set to all zeroes.
• RBBIPT2–RBBIPT0 Most significant byte RBBIPT2 and least significant byte RBBIPT0.
18.50 RECEIVE PORT B PERFORMANCE ALARMS — 0x7A RBPA
TABLE 70. RBPA
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
RBXHEC
RBXBIP
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
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60
(Continued)
The Receive Port B Performance Alarms register contains information about the error performance of Port B. When set RBXHEC
and RBXBIP will raise an interrupt if the corresponding interrupt enable bits are set.
• RBXHEC Receive Port B, Excessive HEC Errors. Set = Number of HEC errors counted in RBHECC is equal to or greater than
the threshold set in RBHECT. This bit is set when RBHECC = RBHECT and can only be cleared by a read of this register.
• RBXBIP Receive Port B, Excessive BIP Errors. Set = Number of BIP errors counted in RBBIPC is equal to or greater than the
threshold set in RBBIPT. This bit is set when RBBIPC = RBBIPT and can only be cleared by a read of this register.
18.51 RECEIVE PORT B PERFORMANCE INTERRUPT ENABLES — 0x7B RBPIE
TABLE 71. RBPIE
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
RBXHECIE
RBXBIPIE
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
This register contains the interrupt enables for the alarms in the RBPA register. Set = interrupt enabled and Clear = interrupt
disabled.
18.52 RECEIVE PORT B REMOTE STATUS AND ALARMS — 0x7C RBRA
TABLE 72. RBRA
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
RBRCS
RBRLOSA
RBRLOSB
RBRBA
RBRDSLL
Type:
Bits[4:2] and [0] Read only/Clear on Read
Bit[1] Read only
Software Lock: No
Reset Value:
0x0D
The Receive Port B Remote Status and Alarms register contains information on the status of the far-end device, which is
connected to Port B. On a local Loss of Signal on Port B, LLOSB alarm, these bits return to their reset values. When set, the
RBRLOSA, RBRLOSB, RBRBA, and RBRDSLL bits will raise an interrupt if the corresponding interrupt enable is set. Also, a
change in value on RBRLOSA, RBRLOSB, RBRDSLL or RBRBA will set the RBRCS bit. When set, the RBRCS bit will raise an
interrupt if the corresponding interrupt enable is set.
• RBRCS Receive Port B, Remote Change of Status at far end device LVDS receive Ports.
• RBRLOSA Receive Port B, Remote Loss Of Signal at far end device LVDS receive Port A.
• RBRLOSB Receive Port B, Remote Loss Of Signal at far end device LVDS receive Port B.
• RBRBA Receive Port B, Remote far end device active receive Port. Set = Port B active and Clear = Port A active. Note that
this bit, if set, will not clear on a read of this register.
• RBRDSLL Receive Port B, Remote far end device active receive port Descrambler Loss of Lock. Set = Out of Lock and Clear
= Lock.
18.53 RECEIVE PORT B REMOTE INTERRUPT ENABLES — 0x7D RBRIE
TABLE 73. RBRIE
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
RBRCSIE
RBRLOSAIE
RBRLOSBIE
RBRBAIE
RBRDSLLIE
Type:
Read/Write
Software Lock: No
Reset Value:
0x00
This register contains the interrupt enables for the alarms in the RBRB register. Set = interrupt enabled and Clear = interrupt
disabled.
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
18.54 RECEIVE PORT B UP2DOWN LOOPBACK CELL COUNT — 0x7E RBU2DLBC
TABLE 74. RBU2DLBC
7
6
5
4
3
2
1
0
RBU2DLBC[7] RBU2DLBC[6] RBU2DLBC[5] RBU2DLBC[4] RBU2DLBC[3] RBU2DLBC[2] RBU2DLBC[1] RBU2DLBC[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The Receive Port B Up2Down Loopback Cell Count register counts the number of incoming loopback cells detected from the Port
B LVDS interface when Up2Down loopback is enabled with the U2DLB bit of the ALBC register, see Section 18.18 ATM AND
LVDS LOOPBACK CONTROL — 0x1A ALBC. Note that this counter is incremented when an incoming loopback cell is received
and that this differs from the functionality of the Down2Up Loopback Cell Count register, see Section 18.71 ATM DOWN2UP
LOOPBACK CELL COUNT — 0xE0 D2ULBCC.
• RBU2DLBC[7:0] Port B Up2Down Loopback Cell Count value. This register will not roll-over from 0x00 to 0xFF but will stick
at 0xFF.
18.55 RECEIVE PORT B CELL DELINEATION THRESHOLDS — 0x80 RBCDT
TABLE 75. RBCDT
7
6
5
4
3
2
1
0
ALPHA[3]
ALPHA[2]
ALPHA[1]
ALPHA[0]
DELTA[3]
DELTA[2]
DELTA[1]
DELTA[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x78
The Receive Port B Cell and Transport Container Delineation Thresholds register controls the operation of the Port B cell
delineation state machine. The cell delineation lock status is refiected in the RBLTCLL bit of the RBLA register.
• ALPHA[3:0] When in lock this is the number of consecutive incorrect cell HEC’s required to lose cell delineation lock.
• DELTA[3:0] When out of lock this is the number of consecutive correct cell HEC’s required to gain cell delineation lock.
18.56 RECEIVE PORT B FRAME DELINEATION THRESHOLDS — 0x81 RBFDT
TABLE 76. RBFDT
7
6
5
4
3
2
1
0
MU[3]
MU[2]
MU[1]
MU[0]
SIGMA[3]
SIGMA[2]
SIGMA[1]
SIGMA[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x78
The Receive Port B Frame Delineation Thresholds register controls the operation of the Port B frame delineation state machine.
The frame delineation lock status is refiected in the RBLFLL bit of the RBLA register.
• MU[3:0] When in lock this is the number of consecutive incorrect cell HEC’s required to lose frame delineation lock.
• SIGMA[3:0] When out of lock this is the number of consecutive correct frame HEC’s required to gain frame delineation lock.
18.57 RECEIVE PORT B DESCRAMBLER LOCK THRESHOLDS — 0x82 RBDSLKT
TABLE 77. RBDSLKT
7
6
5
4
3
2
1
0
PSI[3]
PSI[2]
PSI[1]
PSI[0]
RHO[3]
RHO[2]
RHO[1]
RHO[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x88
The Receive Port B Descrambler Lock Thresholds register controls the operation of the Port B descrambler lock state machine
confidence counter. The descrambler lock status is refiected in the RBLDSLL bit of the RBLA register.
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62
(Continued)
• PSI[3:0] When in lock this is the threshold that the descrambler confidence counter must reach to lose descrambler lock.
When in lock the descrambler confidence counter increments on incorrect HEC predictions and decrements on good HEC
predictions.
• RHO[3:0] When out of lock this is the threshold that the descrambler confidence counter must reach to gain descrambler lock.
When out of lock the descrambler confidence counter decrements on incorrect HEC predictions and increments on good HEC
predictions.
18.58 RECEIVE PORT B BIT ERROR COUNT — 0x83 to 0x85 RBBEC2 to RBBEC0
TABLE 78. RBBEC2–RBBEC0
7
6
5
4
3
2
1
0
RBBEC2 0x83
RBBEC2[7]
RBBEC2[6]
RBBEC2[5]
RBBEC2[4]
RBBEC2[3]
RBBEC2[2]
RBBEC2[1]
RBBEC2[0]
RBBEC1 0x84
RBBEC1[7]
RBBEC1[6]
RBBEC1[5]
RBBEC1[4]
RBBEC1[3]
RBBEC1[2]
RBBEC1[1]
RBBEC1[0]
RBBEC0 0x85
RBBEC0[7]
RBBEC0[6]
RBBEC0[5]
RBBEC0[4]
RBBEC0[3]
RBBEC0[2]
RBBEC0[1]
RBBEC0[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The RBBEC2, RBBEC1 and RBBEC0 registers contain the Port B received bit error count whenever the RBBEC bit of the RBCTL
register is set. If the RBBEC bit of the RBCTL register is clear, these registers are cleared.
• RBBEC2–RBBEC0 This register must be read in the order of most significant byte RBBEC2 first and least significant byte
RBBEC0 last, or the value read will not be valid. This counter will not roll-over from 0xFFFFFF to 0x000000 but will stick at
0xFFFFFF.
18.59 UTOPIA CONFIGURATION — 0xA0 UCFG
TABLE 79. UCFG
7
6
5
4
3
2
1
0
Reserved
Reserved
CLVM[1]
CLVM[0]
BWIDTH
Reserved
UBDEN
UMODE
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x00
The UTOPIA Configuration register defines the UTOPIA interface operating modes. The default is ATM Layer Level 2 mode (31
ports) using CLAV0 with16 bit data.
• CLVM[1:0] Clav Mode bits. 00 = Up to 31 ports using CLAV0, 01 or 10 = Reserved, 11 = Up to 248 ports using CLAV0 to
CLAV7.
• BWIDTH UTOPIA data bus width. Set = 8-bit data bus and Clear = 16-bit mode.
• UBDEN UTOPIA Bidirectional pins enable. Set = the UTOPIA bidirectional pins take on the functionality as defined by the
UMODE setting. Clear = All UTOPIA interface bidirectional pins are tri-stated. This is to avoid pin contention at the UTOPIA
pins on reset.
• UMODE UTOPIA ATM or PHY mode. Set = PHY Layer interface and Clear = ATM Layer Interface.
18.60 UTOPIA CONNECTED PORT LIST — 0xA1 to 0xA4 UCPL3 to UCPL0
TABLE 80. UCPL1–UCPL0
7
6
5
4
3
2
1
0
UCPL3 0xA1
Reserved
UCPL3[6]
UCPL3[5]
UCPL3[4]
UCPL3[3]
UCPL3[2]
UCPL3[1]
UCPL3[0]
UCPL2 0xA2
UCPL2[7]
UCPL2[6]
UCPL2[5]
UCPL2[4]
UCPL2[3]
UCPL2[2]
UCPL2[1]
UCPL2[0]
UCPL1 0xA3
UCPL1[7]
UCPL1[6]
UCPL1[5]
UCPL1[4]
UCPL1[3]
UCPL1[2]
UCPL1[1]
UCPL1[0]
UCPL0 0xA4
UCPL0[7]
UCPL0[6]
UCPL0[5]
UCPL0[4]
UCPL0[3]
UCPL0[2]
UCPL0[1]
UCPL0[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0xFF, except UCPL3 = 0x7F
The UCPL3, UCPL2, UCPL1 and UCPL0 registers define the connected UTOPIA ports for polling. The sub-ports present for the
connected ports is defined in the UCSPL register. Note that at least one port has to be connected for correct polling to occur, so
these registers should never be set to all zeroes. See Section 8.0 UTOPIA Interface Operation. If no ports are required then use
of the Configuration Traffic inhibit functionality is recommended. See Section 10.0 Configuration and Traffic Inhibit Operation.
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
• UCPL3–UCPL0 UCPL3[6] corresponds to port 31 and UCPL0[0] corresponds to port 0. When a bit is set then the port is
connected and will be polled, when clear the port is not connected and will not be polled.
18.61 UTOPIA CONNECTED SUB-PORT LIST — 0xA6 UCSPL
TABLE 81. UCSPL
7
6
5
4
3
2
1
0
UCSPL[7]
UCSPL[6]
UCSPL[5]
UCSPL[4]
UCSPL[3]
UCSPL[2]
UCSPL[1]
UCSPL[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x01
The UCSPL register defines the connected UTOPIA sub-ports within all ports for polling.
• UCSPL UCSPL[7] corresponds to sub-port 7 (CLAV7) and UCSPL[0] corresponds to sub-port 0 (CLAV0). When a bit is set,
then the sub-port is connected and will be polled; when clear, the sub-port is not connected and will not be polled.
18.62 UTOPIA SUB-PORT ADDRESS LOCATION — 0xA7 USPAL
TABLE 82. USPAL
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
USPL[4]
USPL[3]
USPL[2]
USPL[1]
USPL[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x00
The UTOPIA Sub-Port Address Location register defines which byte of the PDU header the sub-port address is contained in when
using Extended UTOPIA mode. The PDU header consists of the User Prepend, the ATM cell header and UDF bytes, and so can
be a maximum of 18 bytes. The first of these bytes is denoted as byte 0. The corresponding USPAM register is used to define
which bits in the byte contain the sub-port address.
• USPAL[4:0] Byte number of the PDU header byte which contains the UTOPIA sub-port address.
18.63 UTOPIA SUB-PORT ADDRESS MASK — 0xA8 USPAM
TABLE 83. USPAM
7
6
5
4
3
2
1
0
USPAM[7]
USPAM[6]
USPAM[5]
USPAM[4]
USPAM[3]
USPAM[2]
USPAM[1]
USPAM[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x07
The UTOPIA Sub-Port Address Mask register defines which bits of the PDU header byte defined by the USPAL register contain
the sub-port address.
• USPAM[7:0] Set = This bit location contains valid sub-port address bit.Clear = Ignore this bit location.
Note that only 3 bit locations must be set in this register to give the 3 bit sub-port address location. All other bits must be clear.
By default, bits USPAM[2:0] are set, indicating that the sub-port address is located in bits [2:0] of the PDU header byte indicated
by the USPAL register, with the MSB in bit [2] and the LSB in bit [0]. If USPAM bits [6], [4] and [1] were set, then the sub-port
address would be located in bits [6], [4] and [1] of the PDU header byte indicated by the USPAL register, with the MSB in bit [6]
and the LSB in bit [1].
18.64 MTB QUEUE THRESHOLD — 0xA9 to 0xC7 MTBQT30 to MTBQT0
TABLE 84. MTBQT30–MTBQT0
7
6
5
4
3
2
1
0
MTBQT30
0xA9
MTBQT30[7]
MTBQT30[6]
MTBQT30[5]
MTBQT30[4]
MTBQT30[3]
MTBQT30[2]
MTBQT30[1]
MTBQT30[0]
MTBQT29
0xAA
MTBQT29[7]
MTBQT29[6]
MTBQT29[5]
MTBQT29[4]
MTBQT29[3]
MTBQT29[2]
MTBQT29[1]
MTBQT29[0]
MTBQT2 0xC5
MTBQT2[7]
MTBQT2[6]
MTBQT2[5]
MTBQT2[4]
MTBQT2[3]
MTBQT2[2]
MTBQT2[1]
MTBQT2[0]
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(Continued)
TABLE 84. MTBQT30–MTBQT0 (Continued)
7
6
5
4
3
2
1
0
MTBQT1 0xC6
MTBQT1[7]
MTBQT1[6]
MTBQT1[5]
MTBQT1[4]
MTBQT1[3]
MTBQT1[2]
MTBQT1[1]
MTBQT1[0]
MTBQT0 0xC7
MTBQT0[7]
MTBQT0[6]
MTBQT0[5]
MTBQT0[4]
MTBQT0[3]
MTBQT0[2]
MTBQT0[1]
MTBQT0[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x04
The MTB Queue Threshold registers define the maximum size, in PDU cells, of each of the 31 queues. If all 31 queues are being
used, it is recommended that the threshold be left at the default of 4 cells. If less than 31 queues are in use, then the queue
threshold may be raised according to Section 9.1 SINGLE BRIDGE MTB CONFIGURATION.
• MTBQT30[7:0] Maximum number of PDU cells for queue 30.
• MTBQT29[7:0] Maximum number of PDU cells for queue 29.
• ...................
• MTBQT1[7:0] Maximum number of PDU cells for queue 1.
• MTBQT0[7:0] Maximum number of PDU cells for queue 0.
18.65 MTB QUEUE FULL — 0xC8 to 0xCB MTBQFL3 to MTBQFL0
TABLE 85. MTBQFL3–MTBQFL0
7
6
5
4
3
2
1
0
MTBQFL3
0xC8
MTBQFL3[7]
MTBQFL3[6]
MTBQFL3[5]
MTBQFL3[4]
MTBQFL3[3]
MTBQFL3[2]
MTBQFL3[1]
MTBQFL3[0]
MTBQT29
0xC9
MTBQFL2[7]
MTBQFL2[6]
MTBQFL2[5]
MTBQFL2[4]
MTBQFL2[3]
MTBQFL2[2]
MTBQFL2[1]
MTBQFL2[0]
MTBQFL1
0xCA
MTBQFL1[7]
MTBQFL1[6]
MTBQFL1[5]
MTBQFL1[4]
MTBQFL1[3]
MTBQFL1[2]
MTBQFL1[1]
MTBQFL1[0]
MTBQFL0
0xCB
MTBQFL0[7]
MTBQFL0[6]
MTBQFL0[5]
MTBQFL0[4]
MTBQFL0[3]
MTBQFL0[2]
MTBQFL0[1]
MTBQFL0[0]
Type:
Read only
Software Lock: No
Reset Value:
0x00
The MTBQFL3, MTBQFL2, MTBQFL1 and MTBQFL0 registers show which queues are full.
• MTBQFL3[7] MTBQFL3[7] bit indicates that the entire MTB is full. As memory resources are over assigned among the 31
individual queues then the MTB may be full while some of the individual queues may not be full. When this bit is set, then the
entire queue is full and when clear, the queue is not full.
• MTBQFL3–MTBQFL0 MTBQFL3[6] corresponds to queue 31 and MTBQFL0[0] corresponds to queue 0. When a bit is set,
then the queue is full and when clear, the queue is not full.
18.66 MTB QUEUE EMPTY — 0xCC to 0xCF MTBQE3 to MTBQE0
TABLE 86. MTBQE3–MTBQE0
7
6
5
4
3
2
1
0
MTBQE3
0xCC
Reserved
MTBQE3[6]
MTBQE3[5]
MTBQE3[4]
MTBQE3[3]
MTBQE3[2]
MTBQE3[1]
MTBQE3[0]
MTBQT29
0xCD
MTBQE2[7]
MTBQE2[6]
MTBQE2[5]
MTBQE2[4]
MTBQE2[3]
MTBQE2[2]
MTBQE2[1]
MTBQE2[0]
MTBQE1 0xCE
MTBQE1[7]
MTBQE1[6]
MTBQE1[5]
MTBQE1[4]
MTBQE1[3]
MTBQE1[2]
MTBQE1[1]
MTBQE1[0]
MTBQE0 0xCF
MTBQE0[7]
MTBQE0[6]
MTBQE0[5]
MTBQE0[4]
MTBQE0[3]
MTBQE0[2]
MTBQE0[1]
MTBQE0[0]
Type:
Read only
Software Lock: No
Reset Value:
0xFF, except MTBQE3 = 0x7F
The MTBQE3, MTBQE2, MTBQE1 and MTBQE0 registers show which queues are empty.
• MTBQE3–MTBQE0 MTBQE3[6] corresponds to queue 31 and MTBQE0[0] corresponds to queue 0. When a bit is set, then
the queue is empty and when clear, the queue is not empty.
18.67 MTB QUEUE FLUSH — 0xD0 to 0xD3 MTBQF3 to MTBQF0
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
TABLE 87. MTBQF3–MTBQF0
7
6
5
4
3
2
1
0
MTBQF3 0xD0
Reserved
MTBQF3[6]
MTBQF3[5]
MTBQF3[4]
MTBQF3[3]
MTBQF3[2]
MTBQF3[1]
MTBQF3[0]
MTBQF2 0xD1
MTBQF2[7]
MTBQF2[6]
MTBQF2[5]
MTBQF2[4]
MTBQF2[3]
MTBQF2[2]
MTBQF2[1]
MTBQF2[0]
MTBQF1 0xD2
MTBQF1[7]
MTBQF1[6]
MTBQF1[5]
MTBQF1[4]
MTBQF1[3]
MTBQF1[2]
MTBQF1[1]
MTBQF1[0]
MTBQF0 0xD3
MTBQF0[7]
MTBQF0[6]
MTBQF0[5]
MTBQF0[4]
MTBQF0[3]
MTBQF0[2]
MTBQF0[1]
MTBQF0[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x00
The MTBQF3, MTBQF2, MTBQF1 and MTBQF0 registers allow each of the queues to be flushed. Flushing a queue removes all
PDU cells from the queue. The processor sets the appropriate bit in the MTBQF register to flush a queue. When this has been
completed, the hardware will clear the bit. So after setting a bit to flush a queue, the processor should poll the MTBQF register
to determine when the flushing has been completed.
• MTBQF3–MTBQF0 MTBQF3[6] corresponds to queue 31 and MTBQF0[0] corresponds to queue 0. When a bit is set, then
a flush of the corresponding queue is initiated and when the queue flush is completed and the queue is now in normal
operation.
18.68 MTB CELL FLUSH — 0xD4 to 0xD7 MTBCF3 to MTBCF0
TABLE 88. MTBCF3–MTBCF0
7
6
5
4
3
2
1
0
MTBCF3 0xD4
Reserved
MTBCF3[6]
MTBCF3[5]
MTBCF3[4]
MTBCF3[3]
MTBCF3[2]
MTBCF3[1]
MTBCF3[0]
MTBCF2 0xD5
MTBCF2[7]
MTBCF2[6]
MTBCF2[5]
MTBCF2[4]
MTBCF2[3]
MTBCF2[2]
MTBCF2[1]
MTBCF2[0]
MTBCF1 0xD6
MTBCF1[7]
MTBCF1[6]
MTBCF1[5]
MTBCF1[4]
MTBCF1[3]
MTBCF1[2]
MTBCF1[1]
MTBCF1[0]
MTBCF0 0xD7
MTBCF0[7]
MTBCF0[6]
MTBCF0[5]
MTBCF0[4]
MTBCF0[3]
MTBCF0[2]
MTBCF0[1]
MTBCF0[0]
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x00
The MTBCF3, MTBCF2, MTBCF1 and MTBCF0 registers allow the PDU cell at the head of each of the queues to be flushed. This
removes the PDU cell from the head of the queue without corrupting the queue. The processor sets the appropriate bit in the
MTBCF register to flush a cell from a queue. When this has been completed, the hardware will clear the bit. So after setting a bit
to flush a cell from a queue, the processor should poll the MTBCF register to determine when the flush has been completed.
• MTBCF3–MTBCF0 MTBCF3[6] corresponds to queue 31 and MTBCF0[0] corresponds to queue 0. When a bit is set, then a
flush of the PDU cell at the head of the queue is initiated and when clear, the cell flush is completed and the queue is now in
normal operation.
18.69 QUEUE FLUSH — 0xD8 QFL
TABLE 89. QFL
7
6
5
4
3
2
1
0
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
FIBFL
MTBFL
Type:
Read/Write
Software Lock: Yes
Reset Value:
0x00
The Queue Flush register allows both the MTB and the FIB queues to be completely flushed. This removes all PDU cells from
either the MTB or FIB queue. The processor sets the appropriate bit in the QFL register to flush a queue. When this has been
completed, the hardware will clear the bit. So after setting a bit to flush a queue the processor should poll the QFL register to
determine when the flush has been completed.
• FIBFL When set, then a flush of the FIB queue is initiated and when clear, the FIB queue flush is completed and the queue
is now in normal operation.
• MTBFL When set, then a flush of the MTB queue is initiated and when clear, the MTB queue flush is completed and the queue
is now in normal operation.
18.70 MTB QUEUE OVERFLOW — 0xD9 to 0xDC MTBQOV3 to MTBQOV0
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(Continued)
TABLE 90. MTBQOV3–MTBQOV0
7
6
5
4
3
2
1
0
MTBQOV3
0xD9
Reserved
MTBQOV3[6]
MTBQOV3[5]
MTBQOV3[4]
MTBQOV3[3]
MTBQOV3[2]
MTBQOV3[1]
MTBQOV3[0]
MTBQT29
0xDA
MTBQOV2[7]
MTBQOV2[6]
MTBQOV2[5]
MTBQOV2[4]
MTBQOV2[3]
MTBQOV2[2]
MTBQOV2[1]
MTBQOV2[0]
MTBQOV1
0xDB
MTBQOV1[7]
MTBQOV1[6]
MTBQOV1[5]
MTBQOV1[4]
MTBQOV1[3]
MTBQOV1[2]
MTBQOV1[1]
MTBQOV1[0]
MTBQOV0
0xDC
MTBQOV0[7]
MTBQOV0[6]
MTBQOV0[5]
MTBQOV0[4]
MTBQOV0[3]
MTBQOV0[2]
MTBQOV0[1]
MTBQOV0[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The MTBQOV3, MTBQOV2, MTBQOV1 and MTBQOV0 registers indicate the overflow status of the thirty-one queues in the
MTB. If a queue has filled to its threshold defined in the MTBQT31–MTBQT0 registers, and an attempt is made to write another
cell to the queue, then the overflow bit for that queue will be set in these registers. These bits reflect that an attempt has been
made to write to an already full queue and may be used as an indication of problems with the Flow Control mechanism. Up to
seven additional cells will be accepted into the queue before a hard overflow occurs. Once the threshold value plus seven cells
has been exceeded any additional cells will be rejected and discarded automatically. A subsequent read of a cell from the specific
queue out over the Utopia interface will be successful, and will clear the overflow bit in this register once the number of cells in
the queue is below the threshold. If any bit in the MTBQOV3–MTBQOV0 registers is set then the MTBSOVA bit of the UAA
register will be set and may raise an interrupt.
• MTBQOV3–MTBQOV0 MTBQOV3[6] corresponds to queue 31 and MTBQOV0[0] corresponds to queue 0. When a bit is set,
then there was an attempt to overflow the corresponding queue.
18.71 ATM DOWN2UP LOOPBACK CELL COUNT — 0xE0 D2ULBCC
TABLE 91. D2ULBCC
7
6
5
4
3
2
1
0
D2ULBCC[7]
D2ULBCC[6]
D2ULBCC[5]
D2ULBCC[4]
D2ULBCC[3]
D2ULBCC[2]
D2ULBCC[1]
D2ULBCC[0]
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The ATM Down2Up Loopback Cell Count register counts the number of outgoing loopback cells detected on the UTOPIA interface
when Down2Up loopback is enabled with the D2ULB bit of the ALBC register, see Section 18.18 ATM AND LVDS LOOPBACK
CONTROL — 0x1A ALBC. Note that this counter is only incremented when a loopback cell is read out of the device.
• D2ULBCC[7:0] Down2Up Loopback Cell Count value. This register will not roll-over from 0x00 to 0xFF but will stick at 0xFF.
18.72 UTOPIA AND ATM ALARMS — 0xE1 UAA
TABLE 92. UAA
7
6
5
4
3
2
1
0
PDULA
CTFRA
D2ULBC
U2DLBC
UPRTY
FIBOVA
MTBSOVA
MTBHOVA
Type:
Read only/Clear on Read
Software Lock: No
Reset Value:
0x00
The UTOPIA and ATM Alarms register monitors the UTOPIA interface, loopbacks and queue overflows. When set these bits will
raise an interrupt if the corresponding interrupt enables are set.
• PDULA PDU Length Alarm bit. Set = PDU length as defined by the PDUCFG register is greater than the maximum PDU cell
length of 64 bytes. Clear = PDU length is less than or equal to maximum of 64 bytes.
• CTFRA Cell Transfer Alarm bit. This alarm is only valid when the device is configured as a PHY layer by setting the UMODE
bit of the UCFG register. It indicates that the controlling ATM layer device has caused an incorrect cell transfer to or from the
DS92UT16. An incorrect cell transfer can only occur when a suspended cell transfer is restarted with an different MPhy
address than initially selected. Set = Incorrect cell transfer has occurred on the UTOPIA transmit or receive interface.
• D2ULBC Set = D2ULBCC count register has changed value.
• U2DLBC Set = RAU2DLBC or RBU2DLBC count registers have changed value.
• UPRTY Set = A parity error has occurred on an incoming ATM cell byte.
67
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DS92UT16TUF
18.0 Register Description
DS92UT16TUF
18.0 Register Description
(Continued)
• FIBOV Set = FIB queue attempted to overflow (Equivalent functionality as the MTBQOV3–0 register bits).
• MTBSOV MTB Soft Overflow Alarm bit. Set = One or more of the bits in the MTBQOV3–MTBQOV0 registers are set. Clear
= The MTBQOV3–MTBQOV0 registers are clear.
• MTBHOV MTB Hard Overflow Alarm bit. Set = MTB queue has attempted to overflow. This is a hard overflow as the overall
MTB has attempted to fill beyond it’s hard limit of 159 cells.
18.73 UTOPIA AND ATM INTERRUPT ENABLES — 0xE2 UAIE
TABLE 93. UAIE
Type:
7
6
5
4
3
2
1
0
PDULIE
CTFRIE
D2ULBCIE
U2DLBCIE
UPRTYIE
FIBOVIE
MTBSOVAIE
MTBHOVIE
Read/Write
Software Lock: No
Reset Value:
0x00
This register contains the interrupt enables for the alarms in the UAA register. Set = interrupt enabled and Clear = interrupt
disabled.
18.74 ATM LOOPBACK CELL FILTER — 0xF7 to 0xFA ALFLT3 to AFLT0
TABLE 94. ALFLT3–ALFLT0
7
6
5
4
3
2
1
0
ALFLT3 0xF7
ALFLT3[7]
ALFLT3[6]
ALFLT3[5]
ALFLT3[4]
ALFLT3[3]
ALFLT3[2]
ALFLT3[1]
ALFLT3[0]
ALFLT2 0xF8
ALFLT2[7]
ALFLT2[6]
ALFLT2[5]
ALFLT2[4]
ALFLT2[3]
ALFLT2[2]
ALFLT2[1]
ALFLT2[0]
ALFLT1 0xF9
ALFLT1[7]
ALFLT1[6]
ALFLT1[5]
ALFLT1[4]
ALFLT1[3]
ALFLT1[2]
ALFLT1[1]
ALFLT1[0]
ALFLT0 0xFA
ALFLT0[7]
ALFLT0[6]
ALFLT0[5]
ALFLT0[4]
ALFLT0[3]
ALFLT0[2]
ALFLT0[1]
ALFLT0[0]
Type:
Read/Write
Software Lock: No
Reset Value:
0xFF
The ALBCF3, ALBCF2, ALBCF1 and ALBCF0 registers (See Section 7.20) define the cell header bytes filter for detecting ATM
loopback cells. Incoming ATM cells are compared against the loopback cell header format defined in the ALBCF3–ALBCF0
registers to determine if they are loopback cells. The filter defined in the ALFLT3–ALFLT0 registers is used to determine which
bits of the four byte cell header are compared. If a bit is set then that bit in the incoming cell header is compared against the
corresponding bit in the ALBCF3–ALBCF0 registers. Only those bits which are set in the ALFLT3–ALFLT0 registers are compared
to determine if a cell is a loopback cell.
• ALBCF3[7:0] Loopback Cell header byte H1 filter.
• ALBCF2[7:0] Loopback Cell header byte H2 filter.
• ALBCF1[7:0] Loopback Cell header byte H3 filter.
• ALBCF0[7:0] Loopback Cell header byte H4 filter.
used to configure the device for scan testing, RAM BIST and
Boundary Scan. The Instruction Register is shown in Figure
23. Bits 12–18 are not used. A more detailed description of
the operation of the TAP controller can be found in the
LOGICVISION document: Adding Logic Test — A Hardware
Reference July 2000. (NOTE: The Internal SCAN and RAM
BIST functions are not user accessible. Therefore, the device user should never assert the Test_se pin.)
19.0 Test Features
19.1 TEST STRUCTURES
The DS92UT16 device has the following test structures in
place.
• Internal SCAN (manufacturing test only)
• RAM BIST (manufacturing test only)
• Boundary SCAN
As shown, the device has a AP controller which was generated using the LOGICVISION tool suite. This AP controller is
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68
DS92UT16TUF
19.0 Test Features
(Continued)
20031622
FIGURE 23. LOGICVISION TAP Instruction Register
The TAP controller contains a device ID register which holds
the device identification. Figure 24 shows the makeup of the
device ID register and the device ID value for the DS92UT16
device.
20031623
DEVICE ID = 0FC2801F
FIGURE 24. Device Identification Register
19.2 BOUNDARY SCAN
The DS92UT16 device contains boundary scan (BS) cells on
all inputs, outputs, bi-directs, and direction control signals.
There are no boundary scan cells on any of the inputs or
outputs from the pins to the LVDS Interface block. The
boundary scan order is shown in Table 95 along with the
type and controlling BS cell for bidirectional BS cells.For
bidirectional pins, if the controlling cell is a logic ‘1’ then they
are outputs.
TABLE 95.
No.
Pin Name
Type
Ctrl.
19
CPU_DATA_1
BIDIR
12
20
CPU_DATA_0
BIDIR
12
21
CPU_ADDR_7
INPUT
N/A
22
CPU_ADDR_6
INPUT
N/A
23
CPU_ADDR_5
INPUT
N/A
24
CPU_ADDR_4
INPUT
N/A
25
CPU_ADDR_3
INPUT
N/A
26
CPU_ADDR_2
INPUT
N/A
CPU_ADDR_1
INPUT
N/A
No.
Pin Name
Type
Ctrl.
27
1
RBPWDN
INPUT
N/A
28
CPU_ADDR_0
INPUT
N/A
2
TXADEN
INPUT
N/A
29
GPIO_TRI_3
ENABLE
N/A
N/A
30
GPIO_3
BIDIR
29
GPIO_TRI_2
ENABLE
N/A
3
TXBDEN
INPUT
4
TPWDN
INPUT
N/A
31
5
TXSYNC
INPUT
N/A
32
GPIO_2
BIDIR
31
GPIO_TRI_1
ENABLE
N/A
6
TXCLK
INPUT
N/A
33
7
CPU_BUSMODE
INPUT
N/A
34
GPIO_1
BIDIR
33
8
CPU_CS_N
INPUT
N/A
35
GPIO_TRI_0
ENABLE
N/A
N/A
36
GPIO_0
BIDIR
35
RESET_N
INPUT
N/A
9
CPU_RD_N
INPUT
10
CPU_WR_N
INPUT
N/A
37
11
CPU_INT_N
OUTPUT
N/A
38
UTFC_MODE
ENABLE
N/A
12
CPU_DATA_TRI
ENABLE
N/A
39
U_TXDATA_15
BIDIR
38
12
40
U_TXDATA_14
BIDIR
38
U_TXDATA_13
BIDIR
38
13
CPU_DATA_7
BIDIR
14
CPU_DATA_6
BIDIR
12
41
15
CPU_DATA_5
BIDIR
12
42
U_TXDATA_12
BIDIR
38
U_TXDATA_11
BIDIR
38
16
CPU_DATA_4
BIDIR
12
43
17
CPU_DATA_3
BIDIR
12
44
U_TXDATA_10
BIDIR
38
18
CPU_DATA_2
BIDIR
12
45
U_TXDATA_9
BIDIR
38
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DS92UT16TUF
19.0 Test Features
(Continued)
No.
Pin Name
Type
Ctrl.
84
U_RXDATA_12
BIDIR
80
Ctrl.
85
U_RXDATA_11
BIDIR
80
U_RXDATA_10
BIDIR
80
TABLE 95. (Continued)
No.
Pin Name
Type
46
U_TXDATA_8
BIDIR
38
86
47
U_TXDATA_7
BIDIR
38
87
U_RXDATA_9
BIDIR
80
38
88
U_RXDATA_8
BIDIR
80
U_RXDATA_7
BIDIR
80
48
U_TXDATA_6
BIDIR
49
U_TXDATA_5
BIDIR
38
89
50
U_TXDATA_4
BIDIR
38
90
U_RXDATA_6
BIDIR
80
38
91
U_RXDATA_5
BIDIR
80
38
92
U_RXDATA_4
BIDIR
80
U_RXDATA_3
BIDIR
80
51
52
U_TXDATA_3
U_TXDATA_2
BIDIR
BIDIR
53
U_TXDATA_1
BIDIR
38
93
54
U_TXDATA_0
BIDIR
38
94
U_RXDATA_2
BIDIR
80
38
95
U_RXDATA_1
BIDIR
80
U_RXDATA_0
BIDIR
80
55
U_TXPARITY
BIDIR
56
U_TXCLAV_6
INPUT
N/A
96
57
U_TXCLAV_5
INPUT
N/A
97
U_RXOSC
BIDIR
80
98
U_RXENB_U_6
OUTPUT
N/A
58
U_TXCLAV_4
INPUT
N/A
59
U_TXCLAV_3
INPUT
N/A
99
U_RXENB_U_5
OUTPUT
N/A
U_RXENB_U_4
OUTPUT
N/A
60
U_TXCLAV_2
INPUT
N/A
100
61
U_TXCLAV_1
INPUT
N/A
101
UUB_CLK
INPUT
N/A
N/A
102
U_RXENB_U_3
OUTPUT
N/A
U_RXENB_U_2
OUTPUT
N/A
62
U_TXCLAV_0
INPUT
63
U_TXCLAV_L_TRI
ENABLE
N/A
103
64
U_TXCLAV_L
BIDIR
63
104
U_RXENB_U_1
OUTPUT
N/A
N/A
105
U_RXENB_U_0
OUTPUT
N/A
N/A
106
U_RXENB_L
BIDIR
38
U_RXCLAV_U_6
INPUT
N/A
65
66
U_TXENB_6
U_TXENB_5
OUTPUT
OUTPUT
67
U_TXENB_4
OUTPUT
N/A
107
68
U_TXENB_3
OUTPUT
N/A
108
U_RXCLAV_U_5
INPUT
N/A
N/A
109
U_RXCLAV_U_4
INPUT
N/A
110
U_RXCLAV_U_3
INPUT
N/A
69
U_TXENB_2
OUTPUT
70
U_TXENB_1
OUTPUT
N/A
71
U_TXENB_0
OUTPUT
N/A
111
U_RXCLAV_U_2
INPUT
N/A
N/A
112
U_RXCLAV_U_1
INPUT
N/A
U_RXCLAV_U_0
INPUT
N/A
72
UDB_CLK
INPUT
73
U_TXENB_L
BIDIR
38
113
74
U_TXSOC
BIDIR
38
114
U_RXCLAV_L_TRI
ENABLE
N/A
38
115
U_RXCLAV_L
BIDIR
114
38
116
U_RXPARITY
BIDIR
80
U_RXADDR_4
BIDIR
38
75
76
U_TXADDR_4
U_TXADDR_3
BIDIR
BIDIR
77
U_TXADDR_2
BIDIR
38
117
78
U_TXADDR_1
BIDIR
38
118
U_RXADDR_3
BIDIR
38
38
119
U_RXADDR_2
BIDIR
38
U_RXADDR_1
BIDIR
38
79
U_TXADDR_0
BIDIR
80
U_RXDATA_TRI
ENABLE
N/A
120
81
U_RXDATA_15
BIDIR
80
121
U_RXADDR_0
BIDIR
38
TEST_SE
INPUT
N/A
RAPWDN
INPUT
N/A
82
U_RXDATA_14
BIDIR
80
122
83
U_RXDATA_13
BIDIR
80
123
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70
DS92UT16TUF
20.0 Package
196-ball LBGA. Dimensions 15 x 15 x 1.37 mm, 1.0 mm ball pitch.
TABLE 96. Pin Locations — BGA196 Package
Ball
Pin Name
Signal Type
Description
A2
AGND
GND
Analog GND for LVDS I/O
A12
AGND
GND
Analog GND for LVDS I/O
B11
AGND
GND
Analog GND for LVDS I/O
B13
AGND
GND
Analog GND for LVDS I/O
C4
AGND
GND
Analog GND for LVDS I/O
C7
AGND
GND
Analog GND for LVDS I/O
C13
AGND
GND
Analog GND for LVDS I/O
E7
AGND
GND
Analog GND for LVDS I/O
B3
AVDD
3.3V
Analog VDD for LVDS I/O
B4
AVDD
3.3V
Analog VDD for LVDS I/O
B12
AVDD
3.3V
Analog VDD for LVDS I/O
B14
AVDD
3.3V
Analog VDD for LVDS I/O
C10
AVDD
3.3V
Analog VDD for LVDS I/O
D7
AVDD
3.3V
Analog VDD for LVDS I/O
J2
CPU_Addr[0]
Input LVTTL
Address Bus
J3
CPU_Addr[1]
Input LVTTL
Address Bus
J1
CPU_Addr[2]
Input LVTTL
Address Bus
H2
CPU_Addr[3]
Input LVTTL
Address Bus
H1
CPU_Addr[4]
Input LVTTL
Address Bus
G1
CPU_Addr[5]
Input LVTTL
Address Bus
F1
CPU_Addr[6]
Input LVTTL
Address Bus
E1
CPU_Addr[7]
Input LVTTL
Address Bus
E6
CPU_BusMode
Input LVTTL
Mode Select for CPU Bus Protocol
E5
CPU_cs
Input LVTTL
Select Signal to Validate the Address Bus for R/W Transfers
J4
CPU_Data[0]
BiDir LVTTL
Data Bus
H3
CPU_Data[1]
BiDir LVTTL
Data Bus
F2
CPU_Data[2]
BiDir LVTTL
Data Bus
H4
CPU_Data[3]
BiDir LVTTL
Data Bus
F3
CPU_Data[4]
BiDir LVTTL
Data Bus
G3
CPU_Data[5]
BiDir LVTTL
Data Bus
G4
CPU_Data[6]
BiDir LVTTL
Data Bus
E2
CPU_Data[7]
BiDir LVTTL
Data Bus
F4
CPU_int
Output LVTTL
Interrupt Request Line
E3
CPU_rd (CPU_ds)
Input LVTTL
Read or Data Strobe, Depending on CPU_BusMode
F5
CPU_wr (CPU_rnw)
Input LVTTL
Write or Read/Write, Depending on CPU_BusMode
B7
DGND
GND
Digital GND
C2
DGND
GND
Digital GND
D11
DGND
GND
Digital GND
E11
DGND
GND
Digital GND
F6
DGND
GND
Digital GND
F9
DGND
GND
Digital GND
G5
DGND
GND
Digital GND
H7
DGND
GND
Digital GND
H8
DGND
GND
Digital GND
H9
DGND
GND
Digital GND
K14
DGND
GND
Digital GND
L1
DGND
GND
Digital GND
71
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DS92UT16TUF
20.0 Package
(Continued)
TABLE 96. Pin Locations — BGA196 Package (Continued)
Ball
Pin Name
Signal Type
Description
N8
DGND
GND
Digital GND
K1
DVDD25
2.5V
VDD for Core Logic
K13
DVDD25
2.5V
VDD for Core Logic
P10
DVDD25
2.5V
VDD for Core Logic
A1
DVDD33
3.3V
Digital VDD
A11
DVDD33
3.3V
Digital VDD
D10
DVDD33
3.3V
Digital VDD
F7
DVDD33
3.3V
Digital VDD
F8
DVDD33
3.3V
Digital VDD
G2
DVDD33
3.3V
Digital VDD
G6
DVDD33
3.3V
Digital VDD
G7
DVDD33
3.3V
Digital VDD
G14
DVDD33
3.3V
Digital VDD
J7
DVDD33
3.3V
Digital VDD
J11
DVDD33
3.3V
Digital VDD
H6
GPIO [0]
BiDir LVTTL
General Purpose Input and Output
H5
GPIO [1]
BiDir LVTTL
General Purpose Input and Output
K2
GPIO [2]
BiDir LVTTL
General Purpose Input and Output
J6
GPIO [3]
BiDir LVTTL
General Purpose Input and Output
E9
JTAG_CLK
Input LVTTL
Boundary Scan Test Clock
E8
JTAG_Reset
Input LVTTL
Boundary Scan Test Circuit Reset
F12
JTAG_TDI
Input LVTTL
Boundary Scan Test Data In
E13
JTAG_TDO
Output LVTTL
Boundary Scan Test Data Out
E10
JTAG_TMS
Input LVTTL
Boundary Scan Test Mode Select
C1
LVDS_ADen
Input LVTTL
Driver Enable for Transmit A
A14
LVDS_ADin[−]
Diff. Input
Input for Receiver Port A
A13
LVDS_ADin[+]
Diff. Input
Input for Receiver Port A
A9
LVDS_ADout[−]
Diff. Output
Output for Driver A
A10
LVDS_ADout[+]
Diff. Output
Output for Driver A
C14
LVDS_ALock_n
Output LVTTL
Lock Signal from Receive Port A
E14
LVDS_APwdn
Input LVTTL
Receive Port A and Deserializer Power Down
B10
LVDS_ARefClk
Input LVTTL
Reference Clock for Receiver A PLL
D14
LVDS_ARxClk
Output LVTTL
Recovered Clock Output from Receive Port A
D2
LVDS_BDen
Input LVTTL
Driver Enable for Transmit B
A3
LVDS_BDin[−]
Diff. Input
Input for Receive Port B
A4
LVDS_BDin[+]
Diff. Input
Input for Receive Port B
A6
LVDS_BDout[−]
Diff. Output
Output for Driver B
A7
LVDS_BDout[+]
Diff. Output
Output for Driver B
C3
LVDS_BLock_n
Output LVTTL
Lock Signal from Receive Port B
B1
LVDS_BPwdn
Input LVTTL
Receive Port B and Deserializer Power Down
D4
LVDS_BRefClk
Input LVTTL
Reference Clock for Receiver B PLL
B2
LVDS_BRxClk
Output LVTTL
Recovered Clock Output from Receive Port B
E4
LVDS_Synch
Input LVTTL
Force SYNC patterns on Transmit A and B
D1
LVDS_TxClk
Input LVTTL
Reference Clock for Driving Transmission Function
D3
LVDS_TxPwdn
Input LVTTL
Powerdown for LVDS Serializer
G8
NC
NO CONNECT
J8
NC
NO CONNECT
K8
NC
NO CONNECT
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72
DS92UT16TUF
20.0 Package
(Continued)
TABLE 96. Pin Locations — BGA196 Package (Continued)
Ball
Pin Name
Signal Type
Description
B8
PGND
GND
GND for Transmit PLL
C8
PGND
GND
GND for Transmit PLL
D8
PGND
GND
GND for Transmit PLL
C9
PGNDA
GND
GND for PLL A
C11
PGNDA
GND
GND for PLL A
C12
PGNDA
GND
GND for PLL A
G9
PGNDA
GND
GND for PLL A
B5
PGNDB
GND
GND for PLL B
B6
PGNDB
GND
GND for PLL B
C5
PGNDB
GND
GND for PLL B
C6
PGNDB
GND
GND for PLL B
A8
PVDD
3.3V
Transmit PLL VDD
B9
PVDD
3.3V
Transmit PLL VDD
D9
PVDDA
3.3V
VDD for PLL A
D12
PVDDA
3.3V
VDD for PLL A
E12
PVDDA
3.3V
VDD for PLL A
A5
PVDDB
3.3V
VDD for PLL B
D5
PVDDB
3.3V
VDD for PLL B
D6
PVDDB
3.3V
VDD for PLL B
L2
Reset_n
Input LVTTL
Chip Reset Control
D13
Test_se
Input LVTTL
Scan Enable
F11
U_RxAddr[0]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
F10
U_RxAddr[1]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
F13
U_RxAddr[2]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
G11
U_RxAddr[3]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
G12
U_RxAddr[4]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
H11
U_RxCLAV [0]
BiDir LVTTL
Receive Cell Available — Normal/Extended PHY Port Control
G13
U_RxCLAV [1]
Input LVTTL
Receive Cell Available — Normal/Extended PHY Port Control
H12
U_RxCLAV [2]
Input LVTTL
Receive Cell Available — Normal/Extended PHY Port Control
F14
U_RxCLAV [3]
Input LVTTL
Receive Cell Available — Normal/Extended PHY Port Control
H13
U_RxCLAV [4]
Input LVTTL
Receive Cell Available — Extended PHY Port Control
H14
U_RxCLAV [5]
Input LVTTL
Receive Cell Available — Extended PHY Port Control
J13
U_RxCLAV [6]
Input LVTTL
Receive Cell Available — Extended PHY Port Control
J14
U_RxCLAV [7]
Input LVTTL
Receive Cell Available — Extended PHY Port Control
N13
U_RxData [0]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
N14
U_RxData [1]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
P14
U_RxData [2]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
L11
U_RxData [3]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
P13
U_RxData [4]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
M12
U_RxData [5]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
P12
U_RxData [6]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
K10
U_RxData [7]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
N12
U_RxData [8]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
P11
U_RxData [9]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
N11
U_RxData [10]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
M11
U_R xData [11]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
M10
U_RxData [12]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
J10
U_RxData [13]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
73
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DS92UT16TUF
20.0 Package
(Continued)
TABLE 96. Pin Locations — BGA196 Package (Continued)
Ball
Pin Name
Signal Type
Description
K9
U_RxData [14]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
L9
U_RxData [15]
BiDir LVTTL
Receive Data Bus, from the PHY Layer Device(s)
J12
U_RxENB [0]
BiDir LVTTL
Enable Data Transfers — Normal/Extended PHY Port Control
L14
U_RxENB [1]
Output LVTTL
Enable Data Transfers — Extended PHY Port Control
M14
U_RxENB [2]
Output LVTTL
Enable Data Transfers — Extended PHY Port Control
L13
U_RxENB [3]
Output LVTTL
Enable Data Transfers — Extended PHY Port Control
G10
U_RxENB [4]
Output LVTTL
Enable Data Transfers — Extended PHY Port Control
J9
U_RxENB [5]
Output LVTTL
Enable Data Transfers — Extended PHY Port Control
K11
U_RxENB [6]
Output LVTTL
Enable Data Transfers — Extended PHY Port Control
L12
U_RxENB [7]
Output LVTTL
Enable Data Transfers — Extended PHY Port Control
H10
U_RxParity
BiDir LVTTL
Receive Data Bus Parity Bit
M13
U_RxSOC
BiDir LVTTL
Receive Start of Cell
L10
U_TxAddr[0]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
N10
U_TxAddr[1]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
M9
U_TxAddr[2]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
L8
U_TxAddr[3]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
N9
U_TxAddr[4]
BiDir LVTTL
Address of MPHY Device Being Polled or Selected
M6
U_TxCLAV [0]
Bidir LVTTL
Utopia Transmit Cell Available — Normal/Extended PHY Control
P4
U_TxCLAV [1]
Input LVTTL
Utopia Transmit Cell Available — Normal/Extended PHY Control
N6
U_TxCLAV [2]
Input LVTTL
Utopia Transmit Cell Available — Normal/Extended PHY Control
K7
U_TxCLAV [3]
Input LVTTL
Utopia Transmit Cell Available — Normal/Extended PHY Control
K6
U_TxCLAV [4]
Input LVTTL
Utopia Transmit Cell Available — Extended PHY Port Control
L5
U_TxCLAV [5]
Input LVTTL
Utopia Transmit Cell Available — Extended PHY Port Control
K5
U_TxCLAV [6]
Input LVTTL
Utopia Transmit Cell Available — Extended PHY Port Control
N5
U_TxCLAV [7]
Input LVTTL
Utopia Transmit Cell Available — Extended PHY Port Control
M5
U_TxData [0]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
P3
U_TxData [1]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
N4
U_TxData [2]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
P2
U_TxData [3]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
M4
U_TxData [4]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
L4
U_TxData [5]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
N3
U_TxData [6]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
P1
U_TxData [7]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
M3
U_TxData [8]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
M2
U_TxData [9]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
N2
U_TxData [10]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
N1
U_TxData [11]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
M1
U_TxData [12]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
L3
U_TxData [13]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
K4
U_TxData [14]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
K3
U_TxData [15]
BiDir LVTTL
Transmit Data Bus, toward the PHY Layer Device(s)
P9
U_TxENB [0]
BiDir LVTTL
Utopia Enable Data Transfers — Normal/Extended PHY Control
P7
U_TxENB [1]
Output LVTTL
Utopia Enable Data Transfers — Extended PHY Control
P6
U_TxENB [2]
Output LVTTL
Utopia Enable Data Transfers — Extended PHY Control
P5
U_TxENB [3]
Output LVTTL
Utopia Enable Data Transfers — Extended PHY Control
N7
U_TxENB [4]
Output LVTTL
Utopia Enable Data Transfers — Extended PHY Control
L7
U_TxENB [5]
Output LVTTL
Utopia Enable Data Transfers — Extended PHY Control
M7
U_TxENB [6]
Output LVTTL
Utopia Enable Data Transfers — Extended PHY Control
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74
DS92UT16TUF
20.0 Package
(Continued)
TABLE 96. Pin Locations — BGA196 Package (Continued)
Ball
Pin Name
Signal Type
Description
L6
U_TxENB [7]
Output LVTTL
Utopia Enable Data Transfers — Extended PHY Control
J5
U_TxParity
BiDir LVTTL
Utopia Transmit Data Bus Parity Bit
M8
U_TxSOC
BiDir LVTTL
Transmit Start of Cell
P8
U_UDBClk
Input LVTTL
Utopia Down Bridge Clock Input
K12
U_UUBClk
Input LVTTL
Utopia Up-Bridge Clock Input
21.0 References
1.
The ATM Forum UTOPIA Level 2, Version 1.0 Specification, af-phy-0039.000, June 1995
2.
ITU-T I.432.1, B-ISDN User Network Interface–Physical
Layer Specification: General Characteristics, August
1996.
75
3.
The ATM Forum User-Network Interface Specification,
Version 3.1, Sept. 1994.
4.
IEEE 1149.1 Standard–JTAG.
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DS92UT16TUF
22.0 Absolute Maximum
Ratings (Note 13)
Package Derating
28.6 mW/˚C
ESD Rating LVDS I/O
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
ESD Rating CMOS I/O
> 3 kV HBM
> 2 kV HBM
Supply Voltage I/O (VCCIO)
Supply Voltage Core Internal (VCCINT)
−0.3V to 3.2V
CMOS/TTL Input and I/O Voltage
−0.3V to 3.6V
CMOS/TTL Output Voltage
LVDS DO/RIN Voltage
Min
Nom
Max
Units
−0.3V to (VCC +0.3V)
Supply Voltage 3.3V
3.0
3.3
3.6
V
−0.3V to 3.6V
Supply Voltage 2.5V
2.37
2.5
2.63
V
Operating Free
Temperature
LVDS Output Short Circuit Duration
Continuous
Junction Temperature
Storage Temperature
23.0 Recommended Operating
Conditions
−0.3V to 4V
+150˚C
−65˚C to +125˚C
Lead Temperature (soldering, 10
seconds)
+225˚C
Max. Package Power Dissipation
Capacity
3.5 W
−40
+25
+85
˚C
CMOS/TTL Input and I/O
Voltage
0
-
+3.6
V
LVDS Input/Output Voltage
0
-
+3.3
V
24.0 Electrical Characteristics
CMOS DC Specifications
Microprocessor Pins, LVDS Control Pins, and Clocks
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14)
Symbol
Parameter
Conditions
Pin/Freq.
Min
Typ
Max
Units
VIH
High Level Input Voltage
2
VCC
V
VIL
Low Level Input Voltage
GND
0.8
V
VCL
Input Clamp Voltage
IIN
Input Current
VIN = 0V or 3.6V
IINH
Input Current for Pulldown
pins
VIN = 0V
IINL
Input Current for Pullup
pins
VIN = 3.6V
Inputs
−10
−0.7
−1.5
V
±2
+10
µA
80
160
µA
−90
−160
µA
VOH
High Level Output Voltage
IOH = 6 mA
2.4
VCC
V
VOL
Low Level Output Voltage
IOL = 6 mA
GND
0.4
V
IOS
Output Short Circuit
Current
VOUT = 0V
IOZ
TRI-STATE Output Current PD* or REN = 0.8V,
VOUT = 0V or VCC V
Outputs
−15
−18
−85
mA
−10
± 0.4
+10
µA
UTOPIA Bus DC Specifications
Pin types are defined inTable 97. Over recommended operating supply and temperature ranges unless otherwise specified.
(Note 14)
Symbol
Parameter
Conditions
Pin/Freq.
Min
Typ
Max
Units
VIH
High Level Input Voltage
2
VCC
V
VIL
Low Level Input Voltage
GND
0.8
V
VCL
Input Clamp Voltage
IIN
Input Current
VIN = 0V or 3.6V
VOH
High Level Output Voltage
IOH = 8 mA
VOL
Low Level Output Voltage
IOL = 8 mA
IOS
Output Short Circuit
Current
VOUT = 0V
−15
IOZ
TRI-STATE Output Current PD* or REN = 0.8V,
VOUT = 0V or VCC V
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Inputs, BiDir
−0.7
−1.5
V
±2
+10
µA
2.4
VCC
V
GND
0.4
V
−85
mA
+10
µA
−10
Output, BiDir
−10
76
± 0.4
(Continued)
Bus LVDS DC Specifications
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14) LVDS Specifications are
for LVDS Input and Output pins only. Control inputs and clocks are specified under Control Pin and Clocks DC Specifications.
Symbol
Parameter
Conditions
VTH
Differential Threshold High VCM = 1.1V
Voltage
VTL
Differential Threshold Low
Voltage
IIN
Input Current
Pin/Freq.
VIN = +2.4V, VCC = 3.6V
or 0V
LVDS_ADin[+,−]
LVDS_BDin[+,−]
VIN = 0V, VCC = 3.6V or
0V
VOD
Output Differential Voltage
(DO+)–(DO−)
DVOD
Output Differential Voltage
Unbalance
VOS
Offset Voltage
IOS
Output Short Circuit
Current
RL = 100Ω
LVDS_ADout[+,−]
LVDS_BDout[+,−]
DO = 0V, DIN = H,
TXPWDN* and DEN =
2.4V
IOZ
TRI-STATE Output Current TXPWDN* or DEN = 0.8V,
DO = 0V or VDD
IOX
Power-Off Output Current
VDD = 0V, DO = 0V or
3.6V
Min
Typ
Max
Units
+50
+100
mV
−100 mV
−50
mV
−10
±5
+10
µA
−10
±5
+10
µA
350
450
550
mV
2
35
mV
0.9
1.0
1.3
V
−35
−50
−70
mA
−10
±1
10
µA
−10
±1
10
µA
Typ
Max
Units
Supply Current, VCC = 2.5V
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14)
Symbol
ICCR
ICCT
Parameter
Conditions
Pin/Freq.
Min
Worst Case Supply
Current
Utopia CL = 15 pF, Bus
LVDS RL = 100Ω, Checker
Pattern, CVDD = 2.63V
52 MHz
200
260
mA
Typical Loading and
Switching
CL = 15 pF, PRBS7 Data
Pattern
33 MHz
112
140
mA
Typ
Max
Units
Supply Current, VCC = 3.3V
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14)
Symbol
ICCR
ICCT
Conditions
Pin/Freq.
Worst Case Supply
Current
Parameter
Utopia CL = 15 pF, Bus
LVDS RL = 100Ω, Checker
Pattern, VDD = 3.6V
Min
52 MHz
270
360
mA
Typical Loading and
Switching
CL = 15 pF, PRBS7 Data
Pattern
33 MHz
140
165
mA
Typ
Max
Units
50
60
%
1
5
%
UTOPIA Bus Switching Characteristics
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14)
Symbol
Parameter
tUCP
Input Clock Period
tUDC
Input Clock Duty Cycle
tUJIT
Input Clock Jitter
Conditions
Pin/Freq.
U_UUBClk,
U_UDBClk
77
Min
20
40
ns
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DS92UT16TUF
24.0 Electrical Characteristics
DS92UT16TUF
24.0 Electrical Characteristics
(Continued)
UTOPIA Bus Switching Characteristics
(Continued)
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14)
Symbol
tUSETUP
Parameter
Conditions
Pin/Freq.
Input Data Valid before
CLK
CL = 30 pF, (Figure 31)
tUHOLD
Input Data Valid after CLK
CL = 30 pF, (Figure 31)
tULH
Output Low-to-High
Transition Time
CL = 30 pF, (Figure 31)
tUHL
Output High-to-Low
Transition Time
CL = 30 pF, (Figure 31)
tUROS
Output Data Valid before
CLK
CL = 30 pF, (Figure 31)
Min
Inputs
Typ
Max
Units
4
ns
1
ns
1
8
ns
1
8
ns
4
ns
1
ns
Outputs
tUROH
Output Data Valid after
CLK
CL = 30 pF, (Figure 31)
tUHZR
High to TRI-STATE Delay
1
16
ns
tULZR
Low to TRI-STATE Delay
1
16
ns
tUZHR
TRI-STATE to High Delay
1
16
ns
tUZLR
TRI-STATE to Low Delay
1
16
ns
Typ
Max
Units
300
400
ps
300
400
ps
60
150
ps
150
ps
(Figure 32)
ATM Mode
PHY Mode
U_TxData[15:0]
Pin Name
Output
Input
U_Tx Parity
Output
Input
Input
*
U_TxCLAV[3:0]
Input
Output
U_TxENB[7:1]
Output
*
U_TxENB[0]
Output
Input
U_TxSOC
Output
Input
U_TxAddr[4:0]
Output
Input
U_RxData[15:0]
Input
Output
U_Rx Parity
Input
Output
U_Rx CLAV[7:4]
Input
*
U_RxCLAV[3:0]
Input
Output
U_RxENB[7:1]
Output
*
U_RxENB[0]
Output
Input
Input
Output
Output
Input
U_Tx CLAV[7:4]
U_RxSOC
U_RxAddr[4:0]
*The extended addressing pins U_TxCLAV[7:4], U_RxCLAV[7:4], U_TxENB[7:1], and
U_RxENB[7:1] are defined for ATM mode only.
LVDS Switching Characteristics
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14)
Symbol
Parameter
Conditions
tLLH
LVDS Low-to-High
Transition Time
RL = 100, CL = 10 pF,
(Figure 25)
tLHL
LVDS High-to-Low
Transition Time
RL = 100, CL = 10 pF,
(Figure 25 )
tRJIT
Random Jitter of LVDS Tx
Clock
tDJIT
Deterministic Jitter of
LVDS Tx Data
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Pin/Freq.
LVDS_ADout[+,−],
LVDS_BDout[+.,−]
78
Min
(Continued)
LVDS Switching Characteristics
(Continued)
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14)
Symbol
tDSR1
Parameter
Conditions
Deserializer PLL Lock
Time from PWRDN (with
SYNCPAT)
(Figure 28)
tDRS2
Deserializer PLL Lock
Time from SYNCPAT
(Figure 29)
tRNM
Deserializer Noise Margin
(Figure 30)
Pin/Freq.
Min
Typ
LVDS_ADin[+,−],
LVDS_BDin[+.,−]
Max
Units
30
µs
12
µs
400
ps
Timing Requirements for Input Clock
LVDS_TxClk, LVDS_ARefClk, LVDS_BRefClk
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14)
Symbol
Parameter
tRFCP
REFCLK Period
tRFDC
REFCLK Duty Cycle
Conditions
Pin/Freq.
Min
Typ
Max
19.2
40
tRFCP/tTCP Ratio of REFCLK to TCLK
Units
ns
50
−5
60
%
5
%
tRFTT
REFCLK Transition Time
(Figure 27)
8
ns
tJIT
Input Jitter
Jitter Frequency < 250 kHz
15
UI
Jitter Frequency < 250 kHz
1.5
UI
Jitter Frequency < 250 kHz
0.15
UI
Microprocessor Interface Switching Characteristics
Over recommended operating supply and temperature ranges unless otherwise specified. (Note 14)
Symbol
tLLH
tLHL
tSETUP
tHOLD
Parameter
Conditions
Low-to-High Transition
Time
CL = 15 pF (Figure 26)
High-to-Low Transition
Time
CL = 15 pF (Figure 26)
Pin/Freq.
Min
Typ
Max
Units
6
ns
6
ns
Outputs
See Section 17.0
Microprocessor Interface
Operation
Inputs
Note 13: Absolute Maximum Ratings are those values beyond which the safety of the device cannot be guaranteed. They are meant to imply that the devices should
be operated at these limits. The table of “Electrical Characteristics” specifies conditions of device operation.
Note 14: Typical values are given for VCC = 3.3V and TA = 25˚C
Note 15: Current into the device is defined as positive. Current out of device pins is defined as negative. Voltages are referenced to ground except VOD, VTH and
VTL which are differential voltages.
Note 16: For the purpose of specifying deserializer PLL performance tDSR1 and tDSR2 are specified with the REFCLK running and stable, and specific conditions
of the incoming data stream (SYNCPATs). tDSR1 is the time required for the deserializer to indicate lock upon power-up or when the power-down mode. tDSR2 is the
time required to indicate lock for the powered-up and enabled deserializer when the input (RI+ and RI−) conditions change from not receiving data to receiving
synchronization patterns (SYNCPATs). The time to lock to random data is dependent upon the incoming data.
Note 17: tRNM is a measure of how much phase noise (jitter) the deserializer can tolerate in the incoming data stream before bit errors occur.
79
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DS92UT16TUF
24.0 Electrical Characteristics
DS92UT16TUF
24.0 Electrical Characteristics
(Continued)
20031628
FIGURE 25. LVDS Rise and Fall times
20031629
FIGURE 26. CMOS Rise and Fall times
20031630
FIGURE 27. REFCLK Transition time
20031634
FIGURE 28. Deserializer lock time tDSR1
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80
DS92UT16TUF
24.0 Electrical Characteristics
(Continued)
20031635
FIGURE 29. Deserializer lock time tDSR2
20031636
FIGURE 30. Deserializer Noise Margin
20031638
FIGURE 31. UTOPIA Setup and Hold Time Definition
20031639
FIGURE 32. UTOPIA TRI-STATE Timing
81
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DS92UT16TUF
24.0 Electrical Characteristics
(Continued)
TABLE 97. UTOPIA Transmit Timing
Signal Name
U_UDBClk,
U_UUBClk
DIR
A→P
U_TxData[15:0],
U_TxPrty,
U_TxSOC,
U_TxEnb[7:0],
U_TxAddr[4:0]
A→P
U_TxClav [7:0]
A←P
Item
f1
Description
TxClk Frequency (nominal)
tT2
TxClk Duty Cycle
tT3
TxClk Peak-to-Peak Jitter
Min
Max
0
50 MHz
40%
60%
—
5%
tT4
TxClk Rise/Fall Time
—
2 ns
tT5
Input Setup to TxClk
4 ns
—
tT6
Input Hold from TxClk
1 ns
—
tT7
Input Setup to TxClk
4 ns
—
tT8
Input Hold from TxClk
1 ns
—
tT9
Signal Going Low Impedance to TxClk
4 ns
—
tT10
Signal Going High Impedance to
TxClk (1)
0 ns
—
tT11
Signal Going Low Impedance from
TxClk
1 ns
—
tT12
Signal Going High Impedance from
TxClk
1 ns
—
TABLE 98. UTOPIA Receive Timing
Signal Name
U_UDBClk,
U_UUBClk
U_RxEnb[7:0],
U_RxAddr[4:0]
U_RxData[15:0],
U_RxParity,
U_RxSOC,
U_RxClav [7:0]
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DIR
A→P
A→P
A←P
Item
f1
Description
RxClk Frequency (nominal)
Min
Max
0
50 MHz
40%
60%
tT2
RxClk Duty Cycle
tT3
RxClk Peak-to-Peak Jitter
—
5%
tT4
RxClk Rise/Fall Time
—
2 ns
tT5
Input Setup to RxClk
4 ns
—
tT6
Input Hold from RxClk
1 ns
—
tT7
Input Setup to RxClk
4 ns
—
tT8
Input Hold from RxClk
1 ns
—
tT9
Signal Going Low Impedance to
RxClk
4 ns
—
tT10
Signal Going High Impedance to
RxClk (2)
0 ns
—
tT11
Signal Going Low Impedance from
RxClk
1 ns
—
tT12
Signal Going High Impedance from
RxClk
1 ns
—
82
DS92UT16TUF
25.0 Appendix A: Layout and
Connection Guidelines
20031624
FIGURE 33. Block Diagram Is a Top View of 196 LBGA Ball Assignment.
83
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DS92UT16TUF
25.0 Appendix A: Layout and
Connection Guidelines (Continued)
tion is to use full power planes to distribute power to these
pins. Using the minimum manufacturing thickness between
the ground and power planes creates a distributed bypass
capacitance. Due to the potentially high inrush currents
caused by Utopia bus output switching, using traces routed
through the array to connect bypass caps to the balls is not
recommended. This is because the inductance of the traces
will negate the affect of the bypass capacitors.
25.1 POWER CONNECTIONS
25.1.1 Digital Supplies (DVDD and DGND)
The digital supply pins provide power to the digital section of
the device. Since the digital supplies are subject to switching
noise, the bypass considerations are important. The DVDD
and DGND balls are located mostly in the center of the ball
array. If the PCB stack-up and signal routing allows placing
bypass caps on the bottom of the board close to the digital
supply pins, then an array of capacitors will provide wide
band bypassing. The total bypass capacitance should be at
least 0.3 µF.
25.2.2 Analog Supplies (AVDD and AGND)
In general, the analog supply pins can be connected to the
digital power planes. The AGND pins should be connected to
a ground plane that connects them directly to the AGND pins
of the sending device. This provides for minimum ground
offset between the devices and provides a return path for the
minute return currents from the LVDS receivers.
The 2.5V supply pins are located near the edge of the
package, which is more convenient for placement of bypass
capacitors. If a power plane supplies the 2.5V, then standard
bypass capacitors of 0.1 µF in parallel with 0.01 µF is sufficient. If the PCB traces connect the 2.5V to the part, then
additional bulk decoupling capacitance should account for
the added trace inductance.
25.2.3 PLL Supplies (PVDD and PGND)
The PLL supply pins should be isolated from the shared
digital and analog power planes. PVDD and PGND pins are
generally grouped together to allow them to be connected to
a split plane or to a “copper pour” on the top layer. The split
plane or copper pour is connected to the power planes
through a PI filter to block low frequency noise. High frequency bypassing should be provided on the PLL side of the
filter to supply switching current to the PLL. A separate filter
for each PLL is recommended. If filters are not desired use a
high value (5 µF to 400 nF) capacitor connected to the PVDD
pins to limit low frequency noise.
25.1.2 Analog Supplies (AVDD and AGND)
The analog VDD and GND power the LVDS driver and receiver section of the device. High frequency bypassing such
as 0.001 µF capacitance is required due to the very high
data rates of the LVDS signals. See Figure 34.
25.1.3 PLL Supplies (PVDD and PGND)
The PLL supply pins provide power for the PLL(s) in the
circuit. The most important function of bypassing or filtering
for the PLL inputs is to attenuate low frequency noise from
entering the PVDD pins. A common source of low frequency
noise is switching power supplies. Power distribution networks should be designed to attenuate any harmonics created by the switching supply. The addition of a PI filter
network at the PVDD pins is optional. See Figure 34.
25.2.4 LVDS I/O
The LVDS I/O pins are located on the outer ring of balls so
they can be routed on the surface layer to minimize added
capacitance. Use surface mount resistors to terminate transmission lines as close to the LVDS inputs as possible. The
LVDS drivers on the DS92UT16 are designed to drive 100Ω
differential lines.
The LVDS A driver outputs (LVDS_Adin[+/−]) are swapped in
position compared to the other LVDS I/O pairs. This allows
them to be “wrapped around ” a connector pin array so that
all of the LVDS signals can be routed on the surface layer.
See Figure 35.
25.2 LAYOUT GUIDELINES
25.2.1 Digital Supplies (DVDD and DGND)
Digital supply connection to bypass capacitors can be difficult, but the more layers in the PCB the easier it is to place
the capacitors near the device. Therefore, the recommenda-
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DS92UT16TUF
25.0 Appendix A: Layout and Connection Guidelines
(Continued)
20031625
FIGURE 34. Recommended bypassing and filtering for the Analog and PLL power supplies on the DS92UT16
Utopia-LVDS Bridge.
20031626
FIGURE 35. Diagram shows routing high-speed LVDS lines on one layer to a connector header.
85
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DS92UT16TUF UTOPIA-LVDS Bridge for 1.6 Gbps Bi-directional Data Transfers
26.0 Physical Dimensions
inches (millimeters) unless otherwise noted
Order Number DS92UT16TUF
See NS Package Number NUJB0196
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