XRT79L71
REV. P1.0.3
PRELIMINARY
1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC
á
348
5
Transmit UTOPIA Parity
Check Enable
R/W
Transmit UTOPIA Parity Check Enable:
This READ/WRITE bit-field permits the user to either enable or dis-
able "Transmit UTOPIA Interface" Parity checking. If the user
enables "Transmit UTOPIA Interface" Parity Checking, then the
Transmit ATM Cell Processor block will compute either the EVEN or
ODD parity value (depending upon the setting of Bit 3 within this reg-
ister) of each byte or 16-bit word that is input via the Transmit UTO-
PIA Data Bus input pins: (TxUData[15:0]). Afterwards, the Transmit
ATM Cell Processor block will compare this "locally computed" parity
value with that which the ATM Layer Processor has provided to the
"TxUPrty" input pin. If the Transmit ATM Cell Processor detects any
discrepancies between these two parity values (e.g., any parity
errors) then it will take action based upon the user's settings for Bit 4
(Transmit UTOPIA Parity Error - Discard).
0 - Disables "Transmit UTOPIA Interface" Parity Checking.
1 - Enables "Transmit UTOPIA Interface" Parity Checking.
4
Transmit UTOPIA Parity
Error - Discard
R/W
Transmit UTOPIA Parity Error - Discard Cell:
This READ/WRITE bit-field permits the user to configure the Trans-
mit ATM Cell Processor block to either discard or retain (for further
processing) any ATM cell that contains a "Transmit UTOPIA Inter-
face" parity error.
0 - Configures the Transmit ATM Cell Processor block to retain (for
further processing) all cells that contain "Transmit UTOPIA Interface"
parity errors.
1 - Configures the Transmit ATM Cell Processor block to discard all
cells that contain "Transmit UTOPIA Interface" parity errors.
N
OTE
:
This bit-field is only valid if "Transmit UTOPIA Interface"
Parity Checking has been enabled.
3
Transmit UTOPIA - Odd
Parity
R/W
Transmit UTOPIA Parity Value - ODD Parity:
This READ/WRITE bit-field permits the user to configure the Trans-
mit ATM Cell Processor block to compute either the EVEN or ODD
parity value for each byte or 16-bit word within each cell that it pro-
cesses. Each of these parity values will ultimately be compared with
the value that is input via the "TxUPrty" input pin (on the Transmit
UTOPIA Interface block) coincident to when ATM cell data is being
applied to the "TxUData[15:0]" input pins.
0 - Configures the Transmit ATM Cell Processor block to compute
and verify the EVEN Parity value of each byte (or 16-bit word) of
ATM cell data that it processes.
1 - Configures the Transmit ATM Cell Processor block to compute
and verify the ODD Parity value of each byte (or 16-bit word) of ATM
cell data that it processes.
N
OTE
:
This bit-field is only value if "Transmit UTOPIA Interface"
Parity Checking has been enabled.
2 - 1
Reserved
R/O
B
IT
N
UMBER
N
AME
T
YPE
D
ESCRIPTION