Filter
Top Products
Receive and Transmit Description
Software Developer’s Manual 23
Table 3-3. Receive Errors (RDESC.ERRORS) Layout
76 5 4321 0
RXE IPE TCPE
RSV
CXE
a
a. 82544GC/EI only.
RSV
SEQ
RSV
b
b. 82541xx, 82547GI/EI, and 82540EP/EM only.
SE
RSV
b
CE
Receive
Descriptor Error
bits
Description
RXE (bit 7)
RX Data Error
Indicates that a data error occurred during the packet reception. A data error in TBI
a
mode (82544GC/EI)/internal SerDes (82546GB/EB and 82545GM/EM) refers to the
reception of a /V/ code (see Section 8.2.1.3). In GMII or MII mode, the assertion of
I_RX_ER during data reception indicates a data error. This bit is valid only when the
EOP and DD bits are set; it is not set in descriptors unless RCTL.SBP (Store Bad
Packets) control bit is set.
IPE (bit 6)
IP Checksum Error
When set, indicates that IP checksum error is detected in the received packet. Valid
only when the IP checksum is performed on the receive packet as indicated via the
IPCS bit in the RDESC.STATUS field.
If receive IP checksum offloading is disabled (RXCSUM.IPOFL), the IPE bit is set to
0b. It has no effect on the packet filtering mechanism.
Reads as 0b.
TCPE (bit 5)
TCP/UDP Checksum Error
When set, indicates that TCP/UDP checksum error is detected in the received
packet.
Valid only when the TCP/UDP checksum is performed on the receive packet as
indicated via TCPCS bit in RDESC.STATUS field.
If receive TCP/UDP checksum offloading is disabled (RXCSUM.TUOFL), the TCPE
bit is set to 0b.
It has no effect on the packet filtering mechanism.
Reads as 0b.
CXE
RSV (bit 4)
Carrier Extension Error
When set, indicates a packet was received in which the carrier extension error was
signaled across the GMII interface. A carrier extension error is signaled by the PHY
by the encoding of 1Fh on the receive data inputs while I_RX_ER is asserted.
Valid only while working in 1000 Mb/s half-duplex mode of operation.
This bit is reserved for all Ethernet controllers except the 82544GC/EI.
RSV (Bit 3)
Reserved
Reads as 0b.