PRELIMINARY
XRT79L71
176
REV. P2.0.0
1-CHANNEL DS3/E3 CLEAR-CHANNEL FRAMERLIU COMBO - CC/HDLC ARCHITECTURE
However, if the Transmit Drive Monitor block ever fails to detect any bipolar pulses (via the TTIP/TRING output
pads) for approximately 128 bit periods, then the XRT79L71 will declare the Transmit Drive Monitor defect
condition. Whenever the XRT79L71 declares the Transmit Drive Monitor defect condition, then it will do all of
the following.
A. It will set Bit 0 (Transmit DMO Condition), within the LIU Alarm Status Register, to "1" as depicted below.
B. It will also generate the Change of DMO Condition Interrupt.
The XRT79L71 will indicate that it is
generating this interrupt by
a.
Asserting the Interrupt Request output pin (e.g., by toggling it "Low")
b. Setting Bit 0 (Change of DMO Condition Interrupt Status) within the LIU Interrupt Status Register,
to "1" as depicted below.
Clearing the Transmit DMO Condition
If the Transmit Drive Monitor block (while declaring the Transmit Drive Monitor Defect Condition) detects at
least one bipolar pulse via the MTIP/MRING input pins, then the XRT79L71 will clear the Transmit Drive
Monitor defect condition. Whenever the XRT79L71 clears the Transmit Drive Monitor defect condition, then it
will do all of the following.
A. It will set Bit 0 (Transmit DMON Condition), within the LIU Alarm Status Register, to "0" as depicted below.
LIU Alarm Status Register (Address = 0x1303)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Unused
Digital LOS
Defect
Declared
Analog LOS
Defect
Declared
FL (FIFO
Limit) Alarm
Declared
Receive LOL
Defect
Declared
Receive LOS
Defect
Declared -
Receive
DS3/E3 LIU
Block
Transmit
DMO
Condition
R/O
0
1
LIU Interrupt Status Register (Address = 0x1302)
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
Unused
Change of
FL
Condition
Interrupt
Status
Change of
LOL
Condition
Interrupt
Status
Change of
LOS
Condition
Interrupt
Status
Change of
DMO
Condition
Interrupt
Status
R/O
RUR
0
1
0
1