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XRT7250
DS3/E3 FRAMER IC
REV. 1.1.1
437
Whenever the Terminal Equipment encounters the
Detection of FEBE Event Interrupt, it should do the
following.
It should read the contents of the PMON FEBE
Event Count Registers (located at Addresses 0x56
and 0x57) in order to determine the number of
FEBE Events that have been received by the
XRT7250 Framer IC.
6.3.6.2.9
The Detection of BIP-8 Error Interrupt
If the Detection of BIP-8 Error Interrupt is enabled,
then the XRT7250 Framer IC will generate an inter-
rupt, anytime the Receive E3 Framer block has de-
tected an error in the EM (Error Monitoring) byte,
within an incoming E3 frame.
Enabling and Disabling the Detection of FEBE
Event Interrupt
The user can enable or disable the Detection of BIP-8
Error’ interrupt by writing the appropriate value into
Bit 2 (BIP-8 Interrupt Enable) within the Rx E3 Inter-
rupt Enable Register - 2, as indicated below.
Setting this bit-field to “1” enables this interrupt. Con-
versely, setting this bit-field to “0” disables this inter-
rupt.
Servicing the Detection of the BIP-8 Error Inter-
rupt
Whenever the XRT7250 Framer IC detects this inter-
rupt, it will do the following.
It will assert the Interrupt Request output pin (INT),
by driving it “High”.
It will set the Bit 2 (BIP-8 Interrupt Status), within
the RxE3 Interrupt Status Register - 2 as indicated
below.
Whenever the Terminal Equipment encounters the
Detection of BIP-8 Error Interrupt, it should do the fol-
lowing.
RXE3 INTERRUPT STATUS REGISTER - 2 (ADDRESS = 0X15)
BIT 7BIT 6BIT 5BIT 4BIT 3BIT 2BIT 1BIT 0
Not Used
TTB
Change
Interrupt
Status
Not Used
FEBE
Interrupt
Status
FERF
Interrupt
Status
BIP-8
Error Interrupt
Status
Framing
Byte Error
Interrupt
Status
RxPld
Mis
Interrupt
Status
RO
RUR
RO
RUR
0
0010
000
RXE3 INTERRUPT ENABLE REGISTER - 2 (ADDRESS = 0X13)
BIT 7BIT 6BIT 5BIT 4BIT 3BIT 2BIT 1BIT 0
Not Used
TTB
Change
Interrupt
Enable
Not Used
FEBE
Interrupt
Enable
FERF
Interrupt
Enable
BIP-8
Error
Interrupt
Enable
Framing
Byte Error
Interrupt
Enable
RxPld
Mis
Interrupt
Enable
RO
R/W
RO
R/W
0
X
000
RXE3 INTERRUPT STATUS REGISTER - 2 (ADDRESS = 0X15)
BIT 7BIT 6BIT 5BIT 4BIT 3BIT 2BIT 1BIT 0
Not Used
TTB
Change
Interrupt
Status
Not Used
FEBE
Interrupt
Status
FERF
Interrupt
Status
BIP-8
Error
Interrupt
Status
Framing
Byte Error
Interrupt
Status
RxPld
Mis
Interrupt
Status
RO
RUR
RO
RUR
0
0000
100