
XRT7245
DS3 UNI FOR ATM
á
PRELIMINARY
REV. 1.03
16
64
RxData2
O
Receive UTOPIA Data Bus Output:
This output pin, along with RxData14 through
RxData0 functions as the Receive UTOPIA Data Bus. ATM cell data that has been
received from the “Far-End” UNI is output on the Receive UTOPIA Data Bus, where it
can be read and processed by the ATM Layer Processor.
65
RxData10
O
Receive UTOPIA Data Bus Output:
This output pin, along with RxData14 through
RxData0 functions as the Receive UTOPIA Data Bus. ATM cell data that has been
received from the “Far-End” UNI is output on the Receive UTOPIA Data Bus, where it
can be read and processed by the ATM Layer Processor.
66
VDD
***
Power Supply Pin
67
RxData9
O
Receive UTOPIA Data Bus Output:
This output pin, along with RxData14 through
RxData0 functions as the Receive UTOPIA Data Bus. ATM cell data that has been
received from the “Far-End” UNI is output on the Receive UTOPIA Data Bus, where it
can be read and processed by the ATM Layer Processor.
68
RxData1
O
Receive UTOPIA Data Bus Output:
This output pin, along with RxData14 through
RxData0 functions as the Receive UTOPIA Data Bus. ATM cell data that has been
received from the “Far-End” UNI is output on the Receive UTOPIA Data Bus, where it
can be read and processed by the ATM Layer Processor.
69
RxData8
O
Receive UTOPIA Data Bus Output:
This output pin, along with RxData14 through
RxData0 functions as the Receive UTOPIA Data Bus. ATM cell data that has been
received from the “Far-End” UNI is output on the Receive UTOPIA Data Bus, where it
can be read and processed by the ATM Layer Processor.
70
RxData0
O
Receive UTOPIA Data Bus Output—LSB:
This output pin, along with RxData14
through RxData0 functions as the Receive UTOPIA Data Bus. ATM cell data that has
been received from the “Far-End” UNI is output on the Receive UTOPIA Data Bus,
where it can be read and processed by the ATM Layer Processor.
71
GND
***
Ground Signal Pin
72
RxSoC
O
Receive UTOPIA Interface—Start of Cell Indicator:
This output pin allows the ATM
Layer Processor to determine the boundaries or the ATM cells that are output via the
Receive UTOPIA Data bus. The Receive UTOPIA Interface block will assert this signal
when the first byte (or word) of a new cell is present on the Receive UTOPIA Data
Bus; RxData[15:0].
73
RxAddr4
I
Receive UTOPIA Address Bus input (MSB):
This input pin, along with RxAddr3
through RxAddr0 functions as the Receive UTOPIA Address bus inputs. These input
pins are only active when the UNI device is operating in the Multi-PHY Mode. The
Receive UTOPIA Address Bus input is sampled on the rising edge of the RxClk signal.
The contents of this address bus are compared with the value stored in the “Rx UT
Address Register (Address = 6Ch). If these two values match, then the UNI will inform
the ATM Layer Processor on whether or not it has any new ATM cells to be read from
the RxFIFO; by driving the RxClav output to the appropriate level. If these two address
values do not match, then the UNI will not respond to the ATM Layer Processor; and
will keep its RxClav output signal tri-stated.
74
RxPrty
O
Receive UTOPIA Interface—Parity Output pin:
The Receive UTOPIA interface block
will compute the odd-parity of each byte (or word) that will place in the Receive UTO-
PIA Data Bus. This odd-parity value will be output on this pin, while the corresponding
byte (or word) is present on the Receive UTOPIA Data Bus.
75
RxAddr3
I
Receive UTOPIA Address Bus input:
(See Description for RxAddr4)
PIN DESCRIPTION (CONT’D)
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ESCRIPTION