XRT84L38IB Exar Corporation, XRT84L38IB Datasheet - Page 78

• Manufacturer Part Number: XRT84L38IB
• Description: Network Controller & Processor ICs 8 Ch T1/E1 Framer
• Manufacturer: Exar Corporation

Specifications of XRT84L38IB

• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

XRT84L38
OCTAL T1/E1/J1 FRAMER
Clock Select Register (CSR) - E1 Mode (Indirect Address = 0xn0H, 0x00H)
B
Violation
Insertion
IT
Bipolar
B
R/W
N
IT
0
UMBER
7
6
5
7
Bipolar Violation Insertion
T1/E1 Select
8KHz Synchronization
Enable
T1, E1
Select
B
R/W
IT
0
6
B
IT
N
AME
Synchroniza-
Enable
8KHz
B
R/W
tion
IT
0
5
B
IT
R/W
R/W
R/W
Clock Loss
Detection
T
Enable
YPE
B
R/W
IT
1
4
Bipolar Violation Insertion:
This READ/WRITE bit-field permits the user to insert Bipolar Vio-
lation to the transmit encoder.
The line coding for the DS1 signal should be bipolar. This signal-
ing technique consists of transmitting a binary "0" as zero volts,
while a binary "1" is transmitted as either a positive or negative
pulse, opposite in polarity to the previous pulse. A Bipolar Viola-
tion occurs when the alternate polarity rule is violated.
A zero-to-one transition of the bit will cause one Bipolar Violation
to be inserted into the outgoing data stream.
T1/E1 Select:
This READ/WRITE bit-field permits the user to select which
mode the framer will be operating.
When this bit is set to one:
The framer is in T1 mode.
When this bit is set to zero:
The framer is in E1 mode.
8KHz Synchronization Enable:
This READ/WRITE bit-field permits the user to activate and de-
activate the 8KHz synchronization of the framer.
An 8KHz external reference clock can be provided to the framer.
When this bit is set to one:
If the Transmit Clock Source Select bits are set to two, the trans-
mit clocks of all eight channels will be synchronized to the exter-
nal applied 8KHz reference clock and thus have the same
frequency and the same phase.
58
Select Bit 1
Frequency
OSCCLK
B
R/W
IT
0
3
Select Bit 0
Frequency
OSCCLK
B
B
R/W
IT
IT
0
D
2
ESCRIPTION
Select Bit1
Transmit
Source
Timing
B
R/W
IT
0
1
Select Bit0
Transmit
Source
Timing
REV. 1.0.1
B
R/W
IT
1
0