NUC970 Technical Reference Manual
Publication Release Date: Dec. 15, 2015
- 635 -
Revision V1.30
NUC97
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CHNIC
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[10]
RDU
Receive Descriptor Unavailable Interrupt
The RDU high indicates that there is no available RX descriptor for packet reception and
RXDMA will stay at Halt state. Once, the RXDMA enters the Halt state, S/W must issues
a write command to RSDR register to make RXDMA leave Halt state while new RX
descriptor is available.
If the RDU is high and RDUIEN (EMACn_MIEN[10]) is enabled, the RXINTR will be high.
Write 1 to this bit clears the RDU status.
0 = RX descriptor is available.
1 = RX descriptor is unavailable.
[9]
DEN
DMA Early Notification Interrupt
The DENI high indicates the EMAC has received the Length/Type field of the incoming
packet.
If the DENI is high and DENIENI (EMACn_MIEN[9]) is enabled, the RXINTR will be high.
Write 1 to this bit clears the DENI status.
0 = The Length/Type field of incoming packet has not received yet.
1 = The Length/Type field of incoming packet has received.
[8]
DFO
Maximum Frame Length Interrupt
The DFOI high indicates the length of the incoming packet has exceeded the length
limitation configured in DMARFC register and the incoming packet is dropped. If the
DFOI is high and MFLEIEN (EMACn_MIEN[8]) is enabled, the RXINTR will be high.
Write 1 to this bit clears the DFOI status.
0 = The length of the incoming packet doesn‟t exceed the length limitation configured in
DMARFC.
1 = The length of the incoming packet has exceeded the length limitation configured in
DMARFC.
[7]
MMP
More Missed Packet Interrupt
The MMP high indicates the MPCNT, Missed Packet Count, has overflow. If the MMP is
high and MMPIEN (EMACn_MIEN[7]) is enabled, the RXINTR will be high. Write 1 to this
bit clears the MMP status.
0 = The MPCNT has not rolled over yet.
1 = The MPCNT has rolled over yet.
[6]
RP
Runt Packet Interrupt
The RP high indicates the length of the incoming packet is less than 64 bytes and the
packet is dropped. If the ARP (EMACn_MCMDR[2]) is set, the short packet is regarded
as a good packet and RP will not be set.
If the RP is high and RPIEN (EMACn_MIEN[6]) is enabled, the RXINTR will be high.
Write 1 to this bit clears the RP status.
0 = The incoming frame is not a short frame or S/W wants to receive a short frame.
1 = The incoming frame is a short frame and dropped.
[5]
ALIE
Alignment Error Interrupt
The ALIE high indicates the length of the incoming frame is not a multiple of byte. If the
ALIE is high and ALIEIEN (EMACn_MIEN[5]) is enabled, the RXINTR will be high. Write
1 to this bit clears the ALIE status.
0 = The frame length is a multiple of byte.
1 = The frame length is not a multiple of byte.
[4]
RXGD
Receive Good Interrupt
The RXGD high indicates the frame reception has completed.
If the RXGD is high and RXGDIEN (EMACn_MIEN[4]) is enabled, the RXINTR will be
high. Write 1 to this bit clears the RXGD status.
0 = The frame reception has not complete yet.
1 = The frame reception has completed.