±15kV ESD Protected MII/RMII 10/100 Ethernet Transceiver with HP Auto-MDIX Support and flexPWR® Technology in a Small Footprint
Datasheet
Table 5.46 Interrupt Management Table (continued)
Mask
30.5
Interrupt Source Flag
Remote Fault Detected
Interrupt Source
Remote Fault
Event to Assert nINT
Rising 1.4
Event to De-Assert nINT
29.5
1.4
Falling 1.4, or
Reading register 1 or
Reading register 29
30.4
30.3
30.2
29.4
29.3
29.2
Link Down
1.2
5.14
6.4
Link Status
Falling 1.2
Rising 5.14
Rising 6.4
Reading register 1 or
Reading register 29
Auto-Negotiation LP
Acknowledge
Acknowledge
Falling 5.14 or
Read register 29
Parallel Detection Fault
Parallel Detection
Fault
Falling 6.4 or
Reading register 6, or
Reading register 29 or
Re-Auto Negotiate or
Link down
30.1
29.1
Auto-Negotiation Page
Received
6.1
Page Received
Rising 6.1
Falling of 6.1 or
Reading register 6, or
Reading register 29
Re-Auto Negotiate, or
Link Down.
a.
If the mask bit is enabled and nINT has been de-asserted while ENERGYON is still high, nINT will assert for
256 ms, approximately one second after ENERGYON goes low when the Cable is unplugged. To prevent an
unexpected assertion of nINT, the ENERGYON interrupt mask should always be cleared as part of the
ENERGYON interrupt service routine.
Note: The ENERGYON bit 17.1 is defaulted to a ‘1’ at the start of the signal acquisition process,
therefore the Interrupt source flag 29.7 will also read as a ‘1’ at power-up. If no signal is
present, then both 17.1 and 29.7 will clear within a few milliseconds.
5.3.2
Alternate Interrupt System
The Alternative method is enabled by writing a ‘1’ to 17.6 (ALTINT).
To set an interrupt, set the corresponding bit of the in the Mask Register 30, (see Table 5.47).
To Clear an interrupt, either clear the corresponding bit in the Mask Register (30), this will de-assert
the nINT output, or Clear the Interrupt Source, and write a ‘1’ to the corresponding Interrupt Source
Flag. Writing a ‘1’ to the Interrupt Source Flag will cause the state machine to check the Interrupt
Source to determine if the Interrupt Source Flag should clear or stay as a ‘1’. If the Condition to De-
Assert is true, then the Interrupt Source Flag is cleared, and the nINT is also de-asserted. If the
Condition to De-Assert is false, then the Interrupt Source Flag remains set, and the nINT remains
asserted.
For example 30.7 is set to ‘1’ to enable the ENERGYON interrupt. After a cable is plugged in,
ENERGYON (17.1) goes active and nINT will be asserted low.
Revision 2.3 (04-12-11)
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