GD32F20x User Manual
818
1:A loss of carrier occurred during frame transmission
10
NCA
No carrier bit
0: PHY carrier sense signal is active
1: The carrier sense signal from the PHY was not asserted during transmission
9
LCO
Late collision bit
If a collision occurs when 64 bytes (including preamble and SFD) has already
transferred, this situation called late collision.
0: No late collision occurred
1: Late collision situation occurred
Note:
This bit is not valid if the UFE bit is set
8
ECO
Excessive collision bit
If the RTD=1 (retry function disable), this bit is set after the first collision.
If the RTD=0 (retry function enable), this bit is set when failed 16 successive retry
transmitting.
When this bit is set, the transmission of current frame is aborted.
0: No excessive collision occurred
1: Excessive collision occurred
7
VFRM
VLAN frame bit
0:The transmitted frame was a normal frame
1: The transmitted frame was a VLAN-type frame
6:3
COCNT[3:0]
Collision count bits
This 4-bit counter value indicates the number of collisions occurring before the
frame was transmitted. The count is not valid when the ECO bit (TDES0[8]) is set
2
EXD
Excessive deferral bit
This is valid when the DFC bit in the MAC configuration register is set
0: No excessive deferral occurred
1: The transmission has ended because of excessive deferral time is over 3036
bytes
1
UFE
Underflow error bit
This bit indicates that the TxDMA comes across an empty TxFIFO while transmitting
the frame before EOF which is caused by pushing data to TxFIFO late from memory.
The transmission process enters the suspend state and sets both the TU (bit 5) and
the TS (bit 0) in ENET_DMA_STAT
0: No underflow error occurred
1: Underflow error occurred and the MAC aborted the frame transmitting
0
DB
Deferred bit
This bit indicates whether the transmitting frame is deferred because of interface
signal CRS is active before MAC transmit frame.
Valid only in Half-duplex mode
0:No transmission deferred
Summary of Contents for GD32F20 Series
Page 191: ...GD32F20x User Manual 191 Bits Fields Descriptions 31 0 TRNDATA 31 0 32 Bit Random data ...
Page 290: ...GD32F20x User Manual 290 conversion is ongoing ...
Page 325: ...GD32F20x User Manual 325 15 0 ALRM 15 0 RTC alarm value low ...
Page 385: ...GD32F20x User Manual 385 ...
Page 523: ...GD32F20x User Manual 523 clears AERR bit by writing 0 to it ...