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IP113M LF
Preliminary Data Sheet
Loop back test (continued)
2.4.2
In-band loop back test
Besides performing the loop back test with an external packet source, IP113M LF supports an easy
alternative. IP113M LF sends out private maintenance frame to do loop back test. All users have to do is
to program MII registers through SMI.
1. Disabe receive function of central TP port and instruct the terminal IP113M LF to perform loop
back and disable T2 timer by programming central IP113M LF through SMI
IP113M LF
(terminal)
IP113M LF
(central)
TP
Maintenance frame
(C1=1, C2-3=10, C8-15=10000000)
MDC, MDIO
(MII reg 24)
TP
Switch
FX
IP113M LF
(terminal)
IP113M LF
(central)
TP
TP
(MII reg 0.14=1)
FX
Switch
2. Terminal IP113M LF runs at loop back mode and acknowledges with maintenance frame
Maintenance frame
(C1=0, C2-3=11, C8-15=10000000)
IP113M LF
(terminal)
IP113M LF
(central)
TP
(MII reg 0.14=1)
3. Central IP113M LF forces test frames to terminal IP113M LF and terminal IP113M LF loops
back the test frames. Central IP113M LF checks the received test frame.
FX
test frame
test frame
TP
Switch
MDC, MDIO
(MII reg 24,25)
IP113M LF
(term inal)
IP113M LF
(central)
TP
Maintenance frame
(C1=1, C2-3=10, C8-15=00000000)
Maintenance fram e
(C1=0, C2-3=11, C8-15=00000000)
(1)
(2)
M DC, MDIO
(MII reg 24)
4. Central IP113M LF ends loop back test enables receive function of TP port and enable LP T 2
tim er
TP
Switch
FX
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April 9, 2007
Copyright © 2004, IC Plus Corp.
IP113M LF-DS-R11