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XRT94L33
xr
Rev.1.2.0.
3-CHANNEL DS3/E3/STS-1 TO STS-3/STM-1 MAPPER IC DATA SHEET
344
Once the Receive STS-3 TOH Processor block declares the SEF defect condition, then it will clear the SEF
Defect Condition if it detects 2 consecutive STS-3 frames with un-erred framing alignment (A1 and A2) bytes.
Once the Receive STS-3 TOH Processor block clears the SEF defect condition, then it will alert the
Microprocessor of this fact by doing the following.
7.
It will indicate that it is clearing the SEF defect condition by setting Bit 1 (SEF Defect Declared), within
the Receive STS-3 Transport Status Register – Byte 0” to “0” as depicted below.
Receive STS-3 Transport Status Register – Byte 0 (Address = 0x1107)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
RDI-L
Defect
Declared
S1 Byte
Unstable
Defect
Declared
K1, K2 Byte
Unstable
Defect
Declared
SF
Defect
Declared
SD
Defect
Declared
LOF
Defect
Declared
SEF
Defect
Declared
LOS
Defect
Declared
R/O
0
8.
It will generate the “Change of SEF Defect Condition” Interrupt. The Receive STS-3 TOH Processor
block will indicate that it is declaring the “Change of SEF Defect Condition” interrupt by doing the
following.
a.
Toggling the “INT*” output pin “LOW”.
b.
b. Setting Bit 1 (Change of SEF Defect Condition Interrupt Status), within the Receive STS-3
Transport Interrupt Status Register – Byte 0” to “1”, as illustrated below.
Receive STS-3 Transport Interrupt Status Register – Byte 0 (Address = 0x110B)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Change of
SF Defect
Condition
Interrupt
Status
Change of
SD Defect
Condition
Interrupt
Status
Detection of
REI-L Error
Interrupt
Status
Detection of
B2 Byte
Error
Interrupt
Status
Detection of
B1 Byte
Error
Interrupt
Status
Change of
LOF Defect
Condition
Interrupt
Status
Change of
SEF Defect
Condition
Interrupt
Status
Change of
LOS Defect
Condition
Interrupt
Status
RUR
0
1
0
2.3.1.3.6
THE LOF (LOSS OF FRAME) DECLARATION AND CLEARANCE CRITERIA
The Receive STS-3 TOH Processor block is capable of declaring and clearing the LOF (Loss of Frame)
defect condition, as described below.
2.3.1.3.6.1
How the Receive STS-3 TOH Processor Block declares the LOF Defect Condition
The Receive STS-3 TOH Processor block will declare the LOF defect anytime the Receive STS-3 TOH
Processor block continuously declares the SEF defect condition for at least 3ms.
Whenever the Receive STS-3 TOH Processor block declares the LOF Defect condition, then it will do the
following.
9.
It will indicate that it is declaring the LOF defect condition by setting Bit 2 (LOS Defect Declared)
within the “Receive STS-3 Transport Status Register – Byte 0” to “1” as depicted below.
Receive STS-3 Transport Status Register – Byte 0 (Address = 0x1107)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
RDI-L
S1 Byte
K1, K2 Byte
SF Defect
SD Defect
LOF Defect
SEF Defect
LOS Defect