CN8223
3.0 Registers
ATM Transmitter/Receiver with UTOPIA Interface
3.3 Configuration Control Registers
100046C
Conexant
3-11
Enables the internal HDLC data link receiver and transmitter. Programming for the
HDLC data link is described in
Section 2.8
.
0x31
—
CONFIG_5 (Configuration Control Register 5)
The CONFIG_5 register is located at address 0x31 and controls miscellaneous functions. Bits 3
–
0 are control
bits which can be written and read. Bits 10, 9, and 8 are read-only status bits.
Bit
Field
Size
Name
Description
15
–
11
5
Reserved
Set to 0.
10
1
Receive G1 Bit 5
Indicates the value of the RDI qualifier bit being received in the G1 octet of the
STS-3c/STM-1 frame. This bit would be used in conjunction with bit 4 in the
LINE_STATUS register [0x38] to determine the type of RDI (Path Yellow) being
received.
9
1
Receive G1 Bit 6
Indicates the value of the RDI qualifier bit being received in the G1 octet of the
STS-3c/STM-1 frame. This bit would be used in conjunction with bit 4 in the
LINE_STATUS register [0x38] to determine the type of RDI (Path Yellow) being
received.
8
1
Receive G1 Bit 7
Indicates the value of the RDI qualifier bit being received in the G1 octet of the
STS-3c/STM-1 frame. This bit would be used in conjunction with bit 4 in the
LINE_STATUS register [0x38] to determine the type of RDI (Path Yellow) being
received.
7
1
Bt8222: Reserved
for Bt8222B and
higher including the
CN8223: Reset
Set to 0.
In Bt8222 revision B and higher, this bit is a software reset. Writing this bit to 1 has
the same affect as high logic level on pin 118, RESET.
6
1
Set G1 X Bits All-1s
Sets the X bits in the G1 octet of the PLCP overhead to all 1s when this bit is high.
When this bit is low, the X bits will be all 0s.
5
1
Enable HDLC Data
Link
4
1
Reserved
Set to 0.
3
1
Transmit G1 Bit 5
Controls the transmission of the qualified RDI signals in the path status octet (G1) in
SONET/SDH modes. The value written to this bit will be placed in the corresponding
bit of the G1 octet.
2
1
Transmit G1 Bit 6
Controls the transmission of the qualified RDI signals in the path status octet (G1) in
SONET/SDH modes. The value written to this bit will be placed in the corresponding
bit of the G1 octet.
1
1
Enable External
Signal Label
Selects the source for the C2 octet in the path overhead for SONET/SDH formats.
When this bit is low, the C2 octet is internally generated. When this bit is high, the
C2 octet is obtained from the TXOVH inputs.
0
1
Transmit Clock
Select
Selects the clock source for the transmitter circuitry. When this bit is low, the
transmit clock is from the TXCKI or TXCKI_HS± inputs. When this bit is high, the
transmit clock is from the RXCKI or RXCKI_HS± inputs to enable loop timing.