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1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC
PRELIMINARY
XRT79L71
REV. P1.0.3
247
RECEIVE ATM CELL PROCESSOR BLOCK - RECEIVE ATM CONTROL REGISTER - BYTE 1 (ADDRESS =
0X1702)
B
IT
7
B
IT
6
B
IT
5
B
IT
4
B
IT
3
B
IT
2
B
IT
1
B
IT
0
Unused
GFC Extrac-
tion Enable
HEC Byte
Correction
Enable
Uncorrect-
able HEC
Byte Error
Discard
COSET Poly-
nomial Addi-
tion
Regenerate
HEC Byte
Enable
R/O
R/O
R/O
R/W
R/W
R/W
R/W
R/W
0
0
0
0
1
0
1
0
B
IT
N
UMBER
N
AME
T
YPE
D
ESCRIPTION
7 - 5
Unused
R/O
4
GFC Extraction Enable
R/W
GFC (Generic Flow Control) Extraction Enable:
This READ/WRITE bit-field permits the user to configure the
Receive ATM Cell Processor block to output the contents of the
GFC Nibble (within each incoming ATM Cell) via the Receive
GFC Value Output port.
0 - Configures the Receive ATM Cell Processor block to NOT
output the contents of the GFC Nibble (within each incoming
ATM cell) via the Receive GFC Value Output port.
1 - Configures the Receive ATM Cell Processor block to output
the contents of the GFC Nibble (within each incoming ATM cell)
via the Receive GFC Value Output port.
3
HEC Byte Correction
Enable
R/W
HEC Byte Correction Enable:
This READ/WRITE bit-field permits the user to enable "Correc-
tion Mode" operation for the Receive ATM Cell Processor block.
If the user implements this configuration option, then the Receive
ATM Cell Processor block will transition into either the "Correc-
tion Mode" or the "Detection Mode" (as "Receive Conditions"
warrant).
If the Receive ATM Cell Processor block is operating in the "Cor-
rection Mode" then it will correct any cells that contain "Single-
Bit" Header byte errors.
In contrast, if the Receive ATM Cell Processor block is operating
in the "Detection Mode", then it will unconditionally discard any
cells that contain Header byte errors (Single-Bit or Multi-Bit
errors).
If the user does not implement this feature, then the Receive
ATM Cell Processor block will only be capable of operating in the
"Detection Mode".
0 - Disables the "Correction Mode". In this setting, the Receive
ATM Cell Processor block will only operate in the "Detection
Mode".
1 - Enables the "Correction Mode". In this setting, the Receive
ATM Cell Processor block will transition into and out of the "Cor-
rection Mode" or "Detection Mode" as receive conditions war-
rant.