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PRELIMINARY
XRT79L71
250
REV. P2.0.0
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
TABLE 34: LIST AND DESCRIPTION OF THE PINS ASSOCIATED WITH THE RECEIVE PAYLOAD DATA OUTPUT
INTERFACE BLOCK
SIGNAL NAME
PIN/BALL #
TYPE
DESCRIPTION
RxSer
A5
O
Receive Serial Payload Data Output pin:
If the Receive Payload Data Output Interface block is operated in the Serial
Mode, then the XRT79L71 will output the payload data that has been
extracted from the incoming DS3 data-stream, via this output pin. The
XRT79L71 will update the data on this pin upon the rising edge of the RxCLK
output clock signal.
The user is advised to design or configure the System-Side Terminal Equip-
ment such that it will sample the data that is output via this output pin, upon
the falling edge of RxCLK.
NOTES:
1.
This signal is only active if the NibIntf input pin is pulled "Low".
2.
In reality, for Serial Mode operation, the entire incoming DS3 data-
stream (payload bits and overhead bits) will be output via the RxSer
output pin. The user will need to use the RxOHInd/RxGapClk signals
in order to distinguish the payload bits from the overhead bits as they
are output via the RxSer output pin.
RxNib[3:0]
B4
A4
D6
C5
O
Receive Nibble-Parallel Payload Data Output Pin:
If the Receive Payload Data Output Interface block is operated in the Nibble-
Parallel Mode, then the XRT79L71 will output the payload data that has been
extracted from the incoming DS3 data-stream, via these output pins, in a Nib-
ble-Parallel manner. The XRT79L71 will update the data via these four output
pins upon the falling edge of the RxCLK output signal.
The user is advised to design or configure the System-Side Terminal Equip-
ment such that it will sample this data upon the rising edge of RxCLK.
NOTES:
1.
These pins are only active if the NibIntf input pin is pulled "High".
2.
In contrast to Serial Mode operation, whenever the XRT79L71 has
been configured to operate in both the DS3 and the Nibble-Parallel
Mode, then only the payload data which has been extracted out of
the incoming DS3 data-stream will be output via these output pins.