XRT79L71 Datasheet, PDF (406/441 Pages) Exar Corporation – 1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC

XRT79L71
REV. P1.0.3
PRELIMINARY
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1 - CHANNEL DS3/E3 ATM UNI/PPP COMBO IC
TRANSMIT ATM CELL PROCESSOR BLOCK - TRANSMIT USER CELL FILTER # 1 - CHECK REGISTER -
BYTE 2 (ADDRESS = 0X1F59)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Transmit User Cell Filter # 1 - Check Register - Byte 2 [7:0]
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
0
0
0
0
0
0
0
0
BIT NUMBER
NAME
7-0
Transmit User Cell Fil-
ter # 1 - Check Regis-
ter - Header Byte 2
TYPE
DESCRIPTION
R/W Transmit User Cell Filter # 1 - Check Register - Header Byte 2:
The User Cell filtering criteria (for Transmit User Cell Filter # 1) is
defined based upon the contents of 9 read/write registers.
These registers are the four "Transmit ATM Cell Processor Block -
Transmit User Cell Filter # 1 - Pattern Registers", the four "Transmit
ATM Cell Processor Block - Transmit User Cell Filter # 1 - Check Reg-
isters" and the "Transmit ATM Cell Processor Block - Transmit User
Cell Filter # 1 Control Register.
This READ/WRITE register, along with the "Transmit ATM Cell Proces-
sor Block - Transmit User Cell Filter # 1 - Pattern Register - Header
Byte 2" permits the user to define the User Cell Filtering criteria for
"Octet # 2" within the incoming User Cell. More specifically, these
READ/WRITE register bits permit the user to specify which bit(s) in
"Octet 2" of the incoming user cell (in the Transmit ATM Cell Processor
Block) are to be checked against the corresponding bit-fields within
the "Transmit ATM Cell Processor Block - Transmit User Cell Filter # 1
- Pattern Register - Header Byte 2" by the User Cell Filter, when deter-
mine whether to "filter" a given User Cell.
Writing a "1" to a particular bit-field in this register, forces the Transmit
User Cell Filter to check and compare the corresponding bit in "Octet
# 2" (of the incoming user cell) with the corresponding bit in the
"Transmit ATM Cell Processor Block - Transmit User Cell Filter # 1 -
Pattern Register - Header Byte 2".
Writing a "0" to a particular bit-field in this register causes the Transmit
User Cell Filter to treat the corresponding bit within "Octet # 2" (in the
incoming user cell) as a "don't care" (e.g., to forgo the comparison
between the corresponding bit in "Octet # 2" of the incoming user cell
with the corresponding bit-field in the "Transmit ATM Cell Processor
Block - Transmit User Cell Filter # 1 - Pattern Register - Header Byte
2").
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