3.3 VOLT TIME SLOT INTERCHANGE
DIGITAL SWITCH WITH RATE
MATCHING
4,096 x 4,096
FEATURES:
••
•
Up to 32 serial input and output streams
••
••
•
Maximum 4,096 x 4,096 channel non-blocking switching
••
••
•
Accepts data streams at 2.048 Mb/s, 4.096 Mb/s, 8.192 Mb/s or
••
16.384 Mb/s
••
Rate matching capability: Mux/Demux mode and Split mode
•
••
••
• Output Enable Indication Pins
••
••
• Per-channel Variable Delay mode for low-latency applications
••
••
• Per-channel Constant Delay mode for frame integrity applications
••
••
•
Automatic identification of ST-BUS® and GCI serial streams
••
••
Automatic frame offset delay measurement
•
••
••
Per-stream frame delay offset programming
•
••
••
• Per-channel high-impedance output control
••
••
• Per-channel Processor mode to allow microprocessor writes to
••
TX streams
••
• Direct microprocessor access to all internal memories
••
••
•
Memory block programming for quick setup
••
••
• IEEE-1149.1 (JTAG) Test Port
••
FUNCTIONAL BLOCK DIAGRAM
IDT72V71643
••
•
Internal Loopback for testing
••
••
•
Available in 144-pin Thin Quad Flatpack (TQFP) and
••
144-pin Ball Grid Array (BGA) packages
••
Operating Temperature Range -40
•
••
••
• 3.3V I/O with 5V tolerant inputs and TTL compatible outputs
••
°°
°C to +85
°°
DESCRIPTION:
The IDT72V71643 has a maximum non-blocking switch capacity of
4,096 x 4,096 channels with data rates at 2.048 Mb/s, 4.096 Mb/s, 8.192 Mb/s
or 16.384 Mb/s. With 32 inputs and 32 outputs, a variety of rate combinations
is supported, under either Mux/Demux mode or Split mode, to allow for
switching between streams of different data rates.
Output enable indications are provided through optional pins (one pin per
output stream, only 16 output streams can be used in this mode) to facilitate
external data bus control.
For applications requiring 32 streams and 32 per-stream Output Enable
indicators, there is also an All Output Enable Feature.
TQFP: 0.50mm pitch, 20mm x 20mm (DA144-1, order code: DA)
NOTES:
1. IC - Internal Connection, tie to Ground for normal operation.
2. All I/O pins are 5V tolerant except for TMS, TDI and TRST.
TDO
TCK
TRST
GND
DS
CS
R/W
A1
A0
VCC
TOP VIEW
3
A3
A4
A2
A5
GND
A9
A7
A8
A6
A10
A11
A12
A13
A14
DTA
VCC
5902 drw03
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
COMMERCIAL TEMPERATURE RANGE
PIN DESCRIPTION
SYMBOLNAMEI/ODESCRIPTION
GNDGround.Ground Rail.
VccVcc+3.3 Volt Power Supply.
TX0-15TX Output 0 to 15OSerial data output stream. These streams may have a data rate of 2.048 Mb/s, 4.096 Mb/s, 8.192 Mb/s,
(Three-state Outputs)or 16.384 Mb/s.
TX16-31/ TX Output 16 to 31/OWhen all 32 output streams are selected via control register, these pins (TX16-31) are output streams 16 to 31
OEI0-15Output Enableand may have a data rate of 2.048 Mb/s, 4.096 Mb/s, 8.192 Mb/s or 16.384 Mb/s. When output enable
Indication 0 to 15indication function is selected, these pins (OEI 0-15) reflect the active or three-state status for the corresponding,
(Three-state Outputs)(TX0-15) output streams.
RX0-31RX Input 0 to 31ISerial data input stream. These streams may have a data rate of 2.048 Mb/s, 4.096 Mb/s, 8.192 Mb/s,
or 16.384 Mb/s.
F0iFrame PulseIThis input accepts and automatically identifies frame synchronization signals formatted according to
ST-BUS® and GCI specifications.
FE/HCLK Frame Evaluation/IWhen the WFPS pin is LOW, this pin is the frame measurement input. When the WFPS pin is HIGH, the HCLK
HCLK Clock(4.096 MHZ clock) is required for frame alignment in the wide frame pulse (WFP) mode.
CLKClockISerial clock for shifting data in/out on the serial streams (RX/TX 0-31).
TMSTest Mode SelectIJTAG signal that controls the state transitions of the TAP controller. This pin is pulled HIGH by an internal
pull-up when not driven.
TDITest Serial Data InIJTAG serial test instructions and data are shifted in on this pin. This pin is pulled HIGH by an internal pull-up
when not driven.
TDOTest Serial Data OutOJTAG serial data is output on this pin on the falling edge of TCK. This pin is held in high-impedance state when
JTAG scan is not enabled.
TCKTest ClockIProvides the clock to the JTAG test logic.
TRSTTest ResetI Asynchronously initializes the JTAG TAP controller by putting it in the Test-Logic-reset state. This pin is pulled
by an internal pull-up when not driven. This pin should be pulsed LOW on power-up, or held LOW, to ensure
that the IDT72V71643 is in the normal functional mode.
RESETDevice ResetIThis input (active LOW) puts the IDT72V71643 in its reset state that clears the device internal counters, registers
and brings TX0-31 and microport data outputs to a high-impedance state. In normal operation, the RESET
pin must be held LOW for a minimum of 100ns to reset the device.
WFPSWide Frame Pulse Select IWhen 1, enables the wide frame pulse (WFP) Frame Alignment interface. When 0, the device operates in
ST-BUS® /GCI mode.
DSData StrobeIThis active LOW input works in conjunction with CS to enable the read and write operations.
R/WRead/WriteIThis input controls the direction of the data bus lines during a microprocessor access.
CSChip SelectIActive LOW input used by a microprocessor to activate the microprocessor port of IDT72V71643.
A0-14Address Bus 0 to 14IThese pins allow direct access to Connection Memory, Data Memory and internal control registers.
D0-15Data Bus 0-15I/OThese pins are the data bits of the microprocessor port.
DTAData TransferOThis active LOW signal indicates that a data bus transfer is complete. When the bus cycle ends, this pin drives
AcknowledgmentHIGH and then goes high-impedance, allowing for faster bus cycles with a weaker pull-up resistor. A pull-up
resistor is required to hold a HIGH level when the pin is in high-impedance.
ODEOutput Drive EnableIThis is the output enable control for the TX0-31 serial outputs. When ODE input is LOW and the OSB bit of
the IMS register is LOW, TX0-31 are in a high-impedance state. If this input is HIGH, the TX0-31 output
drivers are enabled. However, each channel may still be put into a high-impedance state by using the per
channel control bit in the Connection Memory.
4
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
COMMERCIAL TEMPERATURE RANGE
DESCRIPTION (CONTINUED)
The IDT72V71643 is capable of switching up to 4,096 x 4,096 channels
without blocking. Designed to switch 64 Kbit/s PCM or N x 64 Kbit/s data, the
device maintains frame integrity in data applications and minimizes throughput
delay for voice applications on a per channel basis.
The serial input streams (RX) and serial output streams (TX) of the
IDT72V71643 can be run up to 16.384 Mb/s allowing 256 channels per 125µs
frame. Depending on the input and output data rates the device can support
up to 32 serial streams.
With two main operating modes, Processor mode and Connection Mode,
the IDT72V71643 can easily switch data from incoming serial streams (Data
Memory) or from the controlling microprocessor (Connection Memory). As
control and status information is critical in data transmission, the Processor mode
is especially useful when there are multiple devices sharing the input and output
streams.
With three main configuration modes, Regular, Mux/Demux, and Split mode
the IDT72V71643 is designed to work in a mixed data-rate environment. In
Mux/Demux mode, all of the input streams work at one data rate and the output
streams at another. Depending on the configuration, more or less serial streams
will be available on the inputs or outputs to maintain a non-blocking switch. In
Split Mode, half of the input streams are set at one rate, while the other half are
set to another rate. In this mode, both input and output streams are symmetrical.
With data coming from multiple sources and through different paths, data
entering the device is often delayed. To handle this problem, the IDT72V71643
has a frame evaluation feature to allow individual streams to be offset from the
frame pulse in half clock-cycle intervals up to +4.5 clock cycles for speeds up
to 8 Mb/s or +2.5 clock cycles for 16 Mb/s. (See Table 8 for maximum allowable
skew).
The IDT72V71643 also provides a JTAG test access port, an internal
loopback feature, memory block programming, a simple microprocessor
interface and automatic ST-BUS®/GCI sensing to shorten setup time, aid in
debugging and ease use of the device without sacrificing capabilities.
FUNCTIONAL DESCRIPTION
DATA AND CONNECTION MEMORY
All data that comes in through the RX inputs go through a serial-to-parallel
conversion before being stored into internal Data Memory. The 8 KHz frame
pulse (F0i) is used to mark the 125µs frame boundaries and to sequentially
address the input channels in Data Memory. The Data Memory is only written
by the device from the RX streams and can be read from either the TX streams
or the microprocessor.
Data output on the TX streams may come from either the Serial Input Streams
(Data Memory) or from the microprocessor (Connection Memory). In the case
that RX input data is to be output, the addresses in Connection Memory are used
to specify a stream and channel of the input. The Connection Memory is setup
in such a way that each location corresponds to an output channel for each
particular stream. In that way, more than one channel can output the same data.
In Processor mode, the microprocessor writes data to the Connection Memory
locations corresponding to the stream and channel that is to be output. The lower
byte (8 least significant bits) of the Connection Memory is output every frame
until the microprocessor changes the data or mode of the channel. By using this
Processor mode capability, the microprocessor can access input and output
time-slots on a per channel basis.
The most significant bits of the Connection Memory are used to control per
channel functions such as Processor mode, Constant or Variable Delay mode,
three-state of output drivers, and the Loopback function.
OPERATING MODES
In addition to Regular mode where input and output streams are operating
at the same rate, the IDT72V71643 incorporates a rate matching function in two
different modes: Split mode and Mux/Demux mode. In Split mode some of the
input streams are set at one rate, while others are set to another rate. Both input
and output streams are symmetrical. In Mux/Demux mode, all input streams
are operating at the same rate, while output streams are operating at a different
rate. All configurations are non-blocking. These two modes can be entered
by setting the DR3-0 bits in the Control Register, see Table 5.
OUTPUT IMPEDANCE CONTROL
In order to put all streams in three-state, all per-channel three-state control
bits in the Connection Memory are set (MOD0 and MOD1 = 1) or both the ODE
pin and the OSB bit of the Control Register must be zero. If any combination
other than 0-0, for the ODE pin and the OSB bit, is used, the three-state control
of the streams will be left to the state of the MOD1 and MOD0 bits of the Connection
Memory. The IDT72V71643 incorporates a memory block programming
feature to facilitate three-state control after reset. See Table 1 for Output HighImpedance Control.
SERIAL DATA INTERFACE TIMING
When a 16Mb/s serial data rate is required, the master clock frequency
will be running at 16.384MHz resulting in a single-bit per clock. For all other
cases, 2Mb/s, 4Mb/s, and 8Mb/s, the master clock frequency will be twice the
fastest data rate on the serial streams. Use Table 5 to determine clock speed
and DR3-0 bits in the Control Register to setup the device. The IDT72V71643
provides two different interface timing modes, ST-BUS
®
or GCI. The
IDT72V71643 automatically detects the presence of an input frame pulse and
identifies it as either ST-BUS® or GCI.
In ST-BUS®, when running at 16.384MHz, data is clocked out on the
falling edge and is clocked in on the subsquent rising-edge. At all other data
rates, there are two clock cycles per bit and every second falling edge of the
master clock marks a bit boundary and the data is clocked in on the rising edge
of CLK, three quarters of the way into the bit cell. See Figure 17 for timing.
In GCI format, when running at 16.384MHz, data is clocked out on the
rising edge and is clocked in on the subsquent falling edge. At all other data
rates, there are two clock cycles per bit and every second rising edge of the
master clock marks the bit boundary and data is clocked in on the falling edge
of CLK at three quarters of the way into the bit cell. See Figure 18 for timing.
INPUT FRAME OFFSET SELECTION
Input frame offset selection allows the channel alignment of individual input
streams to be offset with respect to the output stream channel alignment (i.e. F0i).
Although input data is synchronous, delays can be caused by variable path
serial backplanes and variable path lengths, which may be implemented in large
centralized and distributed switching systems. Because data is often delayed
this feature is useful in compensating for the skew between clocks.
Each input stream can have its own delay offset value by programming the
frame input offset registers (FOR, Table 7). The frame offset shown is a function
of the data rate, and can be as large as +4.5 master clock (CLK) periods forward
with a resolution of ½ clock period. To determine the maximum offset allowed
see Table 8.
SERIAL INPUT FRAME ALIGNMENT EVALUATION
The IDT72V71643 provides the frame evaluation (FE) input to determine
different data input delays with respect to the frame pulse F0i. Setting the start
frame evaluation (SFE) bit low for at least one frame starts a measurement cycle.
5
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
COMMERCIAL TEMPERATURE RANGE
When the SFE bit in the Control Register is changed from low to high, the
evaluation starts. Two frames later, the complete frame evaluation (CFE) bit of
the frame alignment register (FAR) changes from low to high to signal that a valid
offset measurement is ready to be read from bits 0 to 11 of the FAR register. The
SFE bit must be set to zero before a new measurement cycle is started.
In ST-BUS
®
mode, the falling edge of the frame measurement signal (FE)
is evaluated against the falling edge of the ST-BUS ® frame pulse. In GCI mode,
the rising edge of FE is evaluated against the rising edge of the GCI frame pulse.
See Table 6 and Figure 6 for the description of the frame alignment register.
MEMORY BLOCK PROGRAMMING
The IDT72V71643 provides users with the capability of initializing the entire
Connection Memory block in two frames. To set bits 15 to 13 of every Connection
Memory location, first program the desired pattern in bits 9 to 7 of the Control
Register.
Setting the memory block program (MBP) bit of the control register high
enables the block programming mode. When the block programming enable
(BPE) bit of the Control Register is set to high, the block programming data will
be loaded into the bits 15 to 13 of every Connection Memory location. The other
Connection Memory bits (bit 12 to bit 0) are loaded with zeros. When the memory
block programming is complete, the device resets the BPE bit to zero.
LOOPBACK CONTROL
The loopback control (LPBK) bit of each Connection Memory location allows
the TX output data to be looped backed internally to the RX input for diagnostic
purposes.
If the LPBK bit is high, the associated TX output channel data is internally
looped back to the RX input channel (i.e., data from TXn channel m routes to
the RXn channel m internally); if the LPBK bit is low, the loopback feature is
disabled. For proper per-channel loopback operation, the contents of frame
delay offset registers must be set to zero and the device must be in regular switch
mode (DR3-0 = 0x0, 0x1 or 0x2).
DELAY THROUGH THE IDT72V71643
The switching of information from the input serial streams to the output serial
streams results in a throughput delay. The device can be programmed to
perform time-slot interchange functions with different throughput delay capabilities on a per-channel basis. For voice applications, Variable throughput delay
is best as it ensures minimum delay between input and output data. In wideband
data applications, Constant throughput delay is best as the frame integrity of the
information is maintained through the switch.
The delay through the device varies according to the type of throughput
delay selected in the MOD1 and MOD0 bits of the Connection Memory.
VARIABLE DELAY MODE (MOD1-0 = 0x0)
In this mode, the delay is dependent only on the combination of source and
destination serial stream speed. Although the minimum delay achievable is
dependent on the input and output serial stream speed, if data is switched
out +3 channels of the slowest data rate, the data will be switched out in the same
frame except if the input and output data rates are both 16 Mb/s (DR3-0 = 0x3).
(See Figure 2 for example).
For example, given the input data rate is 2 Mb/s and the output data rate is
8 Mb/s, input channel CH0 can be switch out by output channel CH12. In the
above example the input streams are slower than the output streams. Also, for
every 2 Mb/s time slot there are four 8 Mb/s time slots, thus a three 2 Mb/s channel
delay equates to 12 output channel time slots. See Figure 2 for this example and
other examples of minimum delay to guarantee transmission in the same frame.
CONSTANT DELAY MODE (MOD1-0 = 0x1)
In this mode, frame integrity is maintained in all switching configurations by
making use of a multiple Data Memory buffer. Input channel data is written into
the Data Memory buffers during frame n will be read out during frame n+2.
Figure 1 shows examples of Constant Delay mode.
MICROPROCESSOR INTERFACE
The IDT72V71643’s microprocessor interface looks like a standard RAM
interface to improve integration into a system. With a 15-bit address bus and a
16-bit data bus, read and writes are mapped directly into Data and Connection
memories and require only one Master Clock cycle to access. By allowing the
internal memories to be randomly accessed in one cycle, the controlling
microprocessor has more time to manage other peripheral devices and can
more easily and quickly gather information and setup the switch paths.
Table 2 shows the mapping of the addresses into internal memory blocks,
Table 3 shows the Control Register information and Figure 13 and Figure 14
shows asynchronous and synchronous microprocessor accesses.
MEMORY MAPPING
The address bus on the microprocessor interface selects the internal
registers and memories of the IDT72V71643. The two most significant bits of the
address select between the registers, Data Memory, and Connection Memory.
If A14 and A13 are HIGH, A12-A0 are used to address the Data Memory (Read
Only). If A14 is HIGH and A13 is LOW, A12-A0 are used to address Connection
Memory (Read/Write). If A14 is LOW and A13 is HIGH A12-A9 are used to select
the Control Register, Frame Alignment Register, and Frame Offset Registers.
See Table 2 for mappings.
CONTROL REGISTER
As explained in the Serial Data Interface Timing and Switching Configurations sections, after system power-up, the Control Register should be programmed immediately to establish the desired switching configuration.
The data in the Control Register consists of the Memory Block Programming
bit (MBP), the Block Programming Data (BPD) bits, the Begin Block Programming Enable (BPE), the Output Stand By (OSB), Start Frame Evaluation (SFE),
and Data Rate Select bits (DR 3-0). As explained in the Memory Block
Programming section, the BPE begins the programming if the MBP bit is enabled.
This allows the entire Connection Memory block to be programmed with the
Block Programming Data bits.
CONNECTION MEMORY CONTROL
If the ODE pin or the OSB bit is high, the MOD1-0 bits of each Connection
Memory location controls the output drivers. See Table 1 for detail. The
Processor Channel (PC) mode is entered by a 1-0 of the MOD1-0 of the
Connection Memory. In Processor Channel Mode, this allows the microprocessor to access TX output channels. Once the MOD1-0 bits are set, the lower 8
bits of the Connection Memory will be output on the TX serial streams. Also
controlled in the Connection Memory is the Variable Delay mode or Constant
Delay mode. Each Connection Memory location allows the per-channel
selection between Variable and Constant throughput Delay modes and
Processor mode.
6
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
COMMERCIAL TEMPERATURE RANGE
If the LPBK bit is high, the associated TX output channel data is internally
looped back to the RX input channel (i.e., RXn channel m data comes from the
TXn channel m). If the LPBK bit is low, the loopback feature is disabled. For
proper per-channel loopback operation, the contents of the frame delay offset
registers must be set to zero and the device must be in regular switch mode
(DR3-0 = 0x0, 0x1 or 0x2).
OUTPUT ENABLE INDICATION
The IDT72V71643 has the capability to indicate the state of the outputs (active
or three-state) by enabling the Output Enable Indication (OEI) in the control
register. In the OEI mode however, only half of the output streams are available.
If this same capability is desired with all 32 streams, this can be accomplished
by using two IDT72V71643 devices. In one device, the All Output Enable (AOE)
bit is set to a one while in the other the AOE is set to zero. In this way, one device
acts as the switch and the other as a three-state control device. See Figure 8.
It is important to note if the TSI device is programmed for AOE and the OEI is
also set, the device will be in the AOE mode not OEI.
INITIALIZATION OF THE IDT72V71643
After power up, the IDT72V71643 should be reset. During reset, the internal
registers are put into their default state and all TX outputs are put into three-state.
After reset however, the state of Connection Memory is unknown. As such, the
outputs should be put in high-impedance by holding the ODE low. While the ODE
is low, the microprocessor can initialize the device, program the active paths,
and disable unused outputs by programming the OE bit in Connection Memory.
Once the device is configured, the ODE pin (or OSB bit depending on
initialization) can be switched.
7
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
COMMERCIAL TEMPERATURE RANGE
TABLE 1 — OUTPUT HIGH-IMPEDANCE CONTROL
MOD1-0 BITS INODE PINOSB BIT IN CONTROLOUTPUT DRIVER
CONNECTION MEMORYREGISTERSTATUS
1 and 1Don’t CareDon’t CarePer Channel High-Impedance
Any, other than 1 and 100High-Impedance
Any, other than 1 and 101Enable
Any, other than 1 and 110Enable
Any, other than 1 and 111Enable
TABLE 2 — INTERNAL REGISTER AND ADDRESS MEMORY MAPPING
2. Timeslot A 3 Frames - 1 output channel period maximum delay.
A• • • •Q
• • • •
Figure 1. Constant Delay Mode Examples
(3)
DR3-0 = 4H
DR3-0 = CH
2 Mb/s → 8 Mb/s
2 Mb/s → 8 Mb/s
1 Channel @ 2 Mb/s
(1)
Q
Q
• • • •A
(1)
• • • •A
(2)
(2)
RX 2 Mb/s
TX 8 Mb/s
DR3-0 = AH
DR3-0 = FH
RX 16 Mb/s
TX 8 Mb/s
DR3-0 = 3H
RX 16 Mb/s
TX 16 Mb/s
ABCDEF
1 Channel @ 8 Mb/s
(1,2)
A
(3)
16 Mb/s → 8 Mb/s
16 Mb/s → 8 Mb/s
1 Channel @ 16 Mb/s
ABC DEF GHI J
1 Channel @ 8 Mb/s
(3,4)
16 Mb/s → 16 Mb/s
A or B
(1,2)
C or D
ABCDEFGH I JKLMNO PQR
ABBBA
NOTES:
1. If data is switched at least +3 channel periods of the slower data rate, the data will transmit out in the same frame except if the input and output data rates are both 16 Mb/s
(DR3-0 = 0x3).
2. Delay is a function of input channel and output channel combinations, and input and output stream data rate.
3. See switching mode table for input and output speed combinations.
4. When the input and output data rates are both 16 Mb/s, the minimum delay achievable is 6 time slots.
Figure 2. Variable Delay Mode Examples
9
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
15Reset (Software Reset)A one will reset the device and have the same effect as of the RESET pin. Must be zero for normal operation.
14OEIWhen 1, TX16-31/OEI0-15 will behave as OEI0-15. These outputs will reflect the active or high-impedance state of the corresponding
(Output Enable Indication)output data streams TX0-15. When 0, TX16-31/OEI0-15 will behave as TX16-31 and react in the same way as TX0-15.
13OEPOLWhen 1, a one on OEI pin denotes an active state on the output data stream; zero on OEI pin denotes high-impedance state.
(Output Enable Polarity)When 0, a one denotes high-impedance and a zero denotes an active state.
1 2AOEWhen 1, TX0-31 will behave as OEI0-31 accordingly. These outputs will reflect the active or high-impedance state of the
corresponding output data streams (TX0-31) in another IDT72V71643 if programmed identically.
1 1MBPWhen 1, the Connection Memory block programming feature is ready for the programming of Connection Memory high bits,
(Memory Block Program)bit 13 to bit 15. When 0, this feature is disabled.
10UnusedMust be zero for normal operation.
9- 7BPD2-0These bits carry the value to be loaded into the Connection Memory block whenever the memory block programming feature is
(Block Programming Data) activated. After the MBP bit in the control register is set to 1 and the BPE bit is set to 1, the contents
of the bits BPD2-0 are loaded into bit 15 and 13 of the Connection Memory. Bit 12 to bit 0 of the Connection Memory are set to 0.
6BPEA zero to one transition of this bit enables the memory block programming function. The BPE and BPD2-0 bits in the CR register
(Begin Block Programming have to be defined in the same write operation. Once the BPE bit is set HIGH, the device requires two frames to complete the
Enable)block programming. After the programming function has finished, the BPE bit returns to zero to indicate the operation is completed.
When the BPE=1, the other bit in the control register must not be changed for two frames to ensure proper operation.
5OSBWhen ODE=0 and OSB=0, the output drivers of transmit serial streams are in high-impedance mode. When ODE=1 or OSB=1,
(Output Stand By)the output serial stream drivers function normally.
4SFEA zero to one transition in this bit starts the frame evaluation procedure. When the CFE bit in the FAR register changes from zero
(Start Frame Evaluation)to one, the evaluation procedure stops. To start another frame evaluation cycle, set this bit to zero for at least one frame.
3-0DR3-0Input/Output data rate selection. See Table 5 for detailed programming.
IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
TABLE 6 — FRAME ALIGNMENT REGISTER (FAR) BITS
COMMERCIAL TEMPERATURE RANGE
Reset Value:0000
H.
1514131211109876543210
000CFEFD11FD10FD9FD8FD7FD6FD5FD4FD3FD2FD1FD0
BitNameDescription
15-13UnusedWill be zero when read.
1 2CFE (CompleteWhen CFE = 1, the frame evaluation is completed and bits FD10 to FD0 bits contains a valid frame alignment offset. This bit is reset to
Frame Evaluation)zero, when SFE bit in the CR register is changed from 1 to 0.
11FD11The falling edge of FE (or rising edge for GCI mode) is sampled during the CLK-high phase (FD11 = 1) or during the CLK-low phase
(Frame Delay Bit 11) (FD11 = 0). This bit allows the measurement resolution to ½ CLK cycle.
10-0FD10-0The binary value expressed in these bits refers to the measured input offset value. These bits are rest to zero when the SFE bit of the
(Frame Delay Bits)CR register changes from 1 to 0. (FD10 – MSB, FD0 – LSB)
OFn2, OFn1, OFn0These three bits define how long the serial interface receiver takes to recognize and store bit 0 from the RX input pin: i.e., to start a new frame.
(Offset Bits 2, 1 & 0)The input frame offset can be selected to +4.5 clock periods from the point where the external frame pulse input signal is applied to the F0i
input of the device. See Figure 7.
DLEnST-BUS
®
mode:DLEn = 0, if clock rising edge is at the ¾ point of the bit cell.
(Data Latch Edge)DLEn = 1, if when clock falling edge is at the ¾ of the bit cell.
GCI mode: DLEn = 0, if clock falling edge is at the ¾ point of the bit cell.
DLEn = 1, if when clock rising edge is at the ¾ of the bit cell.
NOTE:
1. n denotes an input stream number from 0 to 31.
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
+ 0.5 clock period shift00000001
+ 1.0 clock period shift10010010
+ 1.5 clock period shift00010011
+ 2.0 clock period shift10100100
+ 2.5 clock period shift00100101
+ 3.0 clock period shift10110110
+ 3.5 clock period shift00110111
+ 4.0 clock period shift11001000
+ 4.5 clock period shift01001001
NOTE:
1. See Table 8 for maximum allowable offsets.
ST-BUS F0i
16.384 MHz CLK
RX Stream
(16.384 Mb/s)
RX Stream
(16.384 Mb/s)
RX Stream
(16.384 Mb/s)
GCI F0i
16.384 MHz CLK
RX Stream
(16.384 Mb/s)
RX Stream
(16.384 Mb/s)
RX Stream
(16.384 Mb/s)
Bit 7
Bit 6
Bit 7
Bit 7
Bit 1Bit 0Bit 2
Bit 0
Bit 0
Bit 6
Bit 1
Bit 5Bit 4
Bit 5Bit 6
Bit 5
Bit 1
Bit 2
Bit 2
Bit 4
offset = 0, DLE = 0
offset = 1, DLE = 0
offset = 0, DLE = 1
offset = 0, DLE = 0
offset = 1, DLE = 0
offset = 0, DLE = 1
5902 drw08
Figure 7. Examples for Input Offset Delay Timing in 16 Mb/s mode
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
ST-BUS F0i
CLK
COMMERCIAL TEMPERATURE RANGE
RX Stream
RX Stream
RX Stream
RX Stream
GCI F0i
CLK
RX Stream
RX Stream
RX Stream
RX Stream
Bit 7
Bit 0
Bit 7
Bit 0
Bit 7
Bit 0
Bit 7
Bit 0
offset = 0, DLE = 0
offset = 1, DLE = 0
offset = 0, DLE = 1
offset = 1, DLE = 1
denotes the 3/4 point of the bit cell
offset = 0, DLE = 0
offset = 1, DLE = 0
offset = 0, DLE = 1
offset = 1, DLE = 1
denotes the 3/4 point of the bit cell
Figure 7. Examples for Input Offset Delay Timing in 8 Mb/s, 4 Mb/s and 2 Mb/s mode (Continued)
5902 drw09
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
COMMERCIAL TEMPERATURE RANGE
JTAG SUPPORT
The IDT72V71643 JTAG interface conforms to the Boundary-Scan standard IEEE-1149.1. This standard specifies a design-for-testability technique
called Boundary-Scan test (BST). The operation of the boundary-scan
circuitry is controlled by an external test access port (TAP) Controller.
TEST ACCESS PORT (TAP)
The Test Access Port (TAP) provides access to the test functions of the
IDT72V71643. It consists of three input pins and one output pin.
•Test Clock Input (TCK)
TCK provides the clock for the test logic. The TCK does not interfere with
any on-chip clock and thus remain independent. The TCK permits shifting of
test data into or out of the Boundary-Scan register cells concurrently with the
operation of the device and without interfering with the on-chip logic.
•Test Mode Select Input (TMS)
The logic signals received at the TMS input are interpreted by the TAP
Controller to control the test operations. The TMS signals are sampled at the
rising edge of the TCK pulse. This pin is internally pulled to V
driven from an external source.
•Test Data Input (TDI)
Serial input data applied to this port is fed either into the instruction register
or into a test data register, depending on the sequence previously applied to
the TMS input. Both registers are described in a subsequent section. The
received input data is sampled at the rising edge of TCK pulses. This pin is
internally pulled to VCC when it is not driven from an external source.
•Test Data Output (TDO)
Depending on the sequence previously applied to the TMS input, the
contents of either the instruction register or data register are serially shifted out
towards the TDO. The data out of the TDO is clocked on the falling edge of the
TCK pulses. When no data is shifted through the boundary scan cells, the TDO
driver is set to a high-impedance state.
•Test Reset (TRST)
Reset the JTAG scan structure. This pin is internally pulled to VCC.
CC when it is not
INSTRUCTION REGISTER
In accordance with the IEEE-1149.1 standard, the IDT72V71643 uses
public instructions. The IDT72V71643 JTAG Interface contains a two-bit
instruction register. Instructions are serially loaded into the instruction register
from the TDI when the TAP Controller is in its shifted-IR state. Subsequently,
the instructions are decoded to achieve two basic functions: to select the test data
register that may operate while the instruction is current, and to define the serial
test data register path, which is used to shift data between TDI and TDO during
data register scanning.
ValueInstruction
00EXTEST
11BYPASS
01 or 10SAMPLE/PRELOAD
JTAG Instruction Register Decoding
TEST DATA REGISTER
As specified in IEEE-1149.1, the IDT72V71643 JTAG Interface contains
two test data registers:
•The Boundary-Scan register
The Boundary-Scan register consists of a series of Boundary-Scan cells
arranged to form a scan path around the boundary of the IDT72V71643 core
logic.
•The Bypass Register
The Bypass register is a single stage shift register that provides a one-bit
path from TDI to its TDO. The IDT72V71643 boundary scan register bits are
shown in Table 10. Bit 0 is the first bit clocked out. All three-state enable bits are
active high.
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
Frame Pulse Setup Time before HCLK 4 MHz falling5 0150ns
Frame Pulse Hold Time from HCLK 4 MHz falling5 0150ns
Frame Pulse Setup Time before HCLK 8 MHz rising4 590ns
Frame Pulse Hold Time from HCLK 8 MHz rising4 590ns
HCLK Period
@ 4.096 MHz244ns
@ 8.192 MHz122ns
Delay between falling edge of HCLK and falling edge of CLK-1 010ns
NOTES:
1. WFPS Pin = 0.
2. WFPS Pin = 1.
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
RESET
t
TX
ODE
CLK
(ST-BUS
WFPS mode)
RZ
or
t
RS
t
ZR
Figure 10. Reset and ODE Timing
COMMERCIAL TEMPERATURE RANGE
t
RZ
t
ODE
5902 drw12
CLK
(GCI mode)
TXVALID DATA
TX
Figure 11. Serial Output and External Control
t
DZ
t
ZD
VALID DATA
5902 drw13
ODE
TX
t
ODE
VALID DATA
t
ODE
5902 drw14
Figure 12. Output Driver Enable (ODE)
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
COMMERCIAL TEMPERATURE RANGE
AC ELECTRICAL CHARACTERISTICS - MICROPROCESSOR INTERFACE TIMING
SymbolParameterMin.Typ.Max.Units
tCSSCS Setup from DS falling0ns
tRWSR/W Setup from DS falling3ns
tADSAddress Setup from DS falling2ns
tCSHCS Hold after DS rising0ns
tRWHR/W Hold after DS Rising3ns
tADHAddress Hold after DS Rising2ns
(1)
tDDR
(1,2,3)
tDHR
tDSWData Setup on Write (Fast Write)1 0ns
tSWDValid Data Delay on Write (Slow Write)-0ns
tDHWData Hold on Write5ns
tDSPWDS Pulse Width5ns
tCKAKClock to ACK35ns
(1)
t
AKD
(1,2,3)
tAKH
(4)
t
DSS
Data Setup from DTA LOW on Read2ns
Data Hold on Read1 01 52 5ns
IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096
COMMERCIAL TEMPERATURE RANGE
AC ELECTRICAL CHARACTERISTICS
(1)
SERIAL STREAM (ST-BUS® and GCI)
SymbolParameterMin.Typ.Max.Units
tSISRX Setup Time2ns
tSIHRX Hold Time1 0ns
tSODTX Delay – Active to Active22ns
(1)
tDZ
tZD
tODE
(1)
(1)
TX Delay – Active to High-Z22ns
TX Delay – High-Z to Active22ns
Output Driver Enable (ODE) Delay30ns
tOEIEOutput Enable Indicator (OEI) Enable40ns
tOEIDOutput Enable Indicator (OEI) Disable25ns
tRZActive to High-Z on Master Reset30ns
tZRHigh-Z to Active on Master Reset30ns
t
RsReset pulse width10 0ns
NOTE:
1. High-Impedance is measured by pulling to the appropriate rail with R
(1KΩ), with timing corrected to cancel time taken to discharge CL (150 pF).
L
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IDT72V71643 3.3V TIME SLOT INTERCHANGE
DIGITAL SWITCH 4,096 x 4,096