
PRELIMINARY
XRT86SH328
179
REV. P1.0.6
28-CHANNEL DS1/E1 FRAMER/LIU WITH DS3 MUX & VT-MAPPER - SONET APPLICATIONS
BIT6 - Set DS3 Mode
To use the Transmit and Receive DS3 Framer blocks, within the XRT86SH328, then the user MUST set this bit-field to
1.
BIT 5 - Internal LOS Enable
This READ/WRITE bit-field is used to enable or disable the Internal LOS Detector within the Receive DS3 Framer block.
If the user enables the Internal LOS Detector, then the Receive DS3 Framer block will be configured to check the
incoming DS3 signal for a sufficient number of consecutive all zero bits and it will declare and clear the LOS defect
condition based upon the 1s density and the number of consecutive 0bits within the incoming DS3 data-stream.
If the user disables the Internal LOS Detector, then the Receive DS3 Framer block will NOT be configured to check the
incoming DS3 data-stream for a sufficient number of consecutive 0 bits, and it will NOT declare nor clear the LOS defect
condition based upon the 1s density and the number of consecutive 0 bits within the incoming DS3 data-stream.
`
0 - Disables the Internal LOS Detector
`
1 - Enables the Internal LOS Detector.
BIT 4 - DS3 Framer Block Software RESET
This READ/WRITE bit-field is used to execute a Software RESET to the Transmit and Receive DS3 Framer block. If
the user executes this Software RESET, then the contents of the Transmit/Receive DS3 Framer block configuration
registers will not be reset to their default values. Instead, internal state machines (within the Transmit and Receive DS3
Framer blocks) will be reset.
`
A 0 to 1 transition in this bit-field commands a Software RESET to Transmit and Receive DS3 Framer block.
BIT 3 - Reserved
BIT 2 - Frame Format
This READ/WRITE bit-field is used to configure the Transmit and Receive DS3 Framer blocks to operate in
either the C-Bit Parity or the M13/M23 Framing formats.
`
0 - Configures the Transmit and Receive DS3 Framer blocks to operate in the C-bit Parity Framing format.
`
1 - Configures the Transmit and Receive DS3 Framer blocks to operate in the M13/M23 Framing format.
BIT[1:0] - Transmit DS3 Framer Block Timing Reference Select[1:0]
The user should set these bit-fields to either [1, 0] or [1, 1] for proper operation.
BIT7 - Disable Transmit Loss of Clock Feature
This READ/WRITE bit-field is used to either enable or disable the Transmit Loss of Clock feature.
If this feature is enabled, then the DS3 Framer block will enable some circuitry that will terminate the current READ or
WRITE access (to the Microprocessor Interface), if a Loss of Transmit Clock Event were to occur.
The intent behind this feature is to prevent any READ/WRITE accesses (to the DS3 Framer blocks) from hanging in the
event of a Loss of Clock event.
`
0 - Enables the Transmit Loss of Clock feature.
`
1 - Disables the Transmit Loss of Clock feature
BIT6 - LOC
BIT 5 - Disable Receive Loss of Clock Feature
This READ/WRITE bit-field is used to either enable or disable the Receive Loss of Clock feature.
If this feature is enabled, then the DS3 Framer block will enable some circuitry that will terminate the current READ or
T
ABLE
239: DS3 F
RAMER
B
LOCK
- I/O C
ONTROL
R
EGISTER
(A
DDRESS
= 0
X
0E01)
BIT7
BIT6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Disable
TxLOC
LOC
Disable
RxLOC
Unused
Transmit
Line Clock
Invert
Receive Line
Clock Invert
Reframe
R/W
R/O
R/W
R/O
R/O
R/W
R/W
R/W
1
0
1
0
0
0
0
0