HS_Media independent interface (MII)
RM0082
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Doc ID 018672 Rev 1
[11]
OE
Overflow Error.
If set, it indicates that received frame was damaged due to
buffer overflow in MAC core.
[10]
VLAN
Van Tag.
If set, it indicates that the frame pointed to by this descriptor is a
VLAN frame tagged by the MAC core.
[09]
FS
First Descriptor.
If set, this descriptor contains the first buffer of the frame.
[08]
LS
Last Descriptor.
If set, it indicates that the buffers pointed to by this
descriptor are the last buffers of the frame.
[07]
IPC
checksum
error
If set, it indicates that the 16 bit IP header checksum calculated by the MAC
core did not match the received checksum bytes.
[06]
LC
Late Collision
. If set, it indicates that late collision has occurred while
receiving the frame in half-duplex mode.
[05]
FT
Frame type
. If set, it indicates that the received frame is an Ethernet-type
frame, whereas the received frame is an IEEE802.3 frame.
[04]
RWT
Receive watchdog timeout. If set, it indicates that the receive watchdog timer
has expired while receiving the current frame and the current frame is
truncated after the watchdog timeout.
[03]
RE
Receive Error.
[02]
DE
Dribble Bit Error.
If set, it indicates that the received frame has a non-
integer multiple of bytes (odd nibbles). Valid only in MII mode.
[01]
CE
CRC Error.
[00]
Rx MAC
address
If set, it indicates that the Rx MAC address value (register1 to register15)
matched the DA field of the frame. If cleared, it indicates that Rx MAC
Address0 matched the DA field.
Table 419.
Receive descriptor 1 (RDES1)
Bit
Name
Description
[31]
DIC
Disable Interrupt on Completion Setting this bit will prevent the setting of the
RI bit of the Status register
) for the received frame that ends in the
buffer pointer to by this descriptor. This, in turn, will disable the assertion of
the interrupt to the host due to RI.
[30:29] Reserved
-
[28:16] RBS2
Receive Buffer 2 Size.
These 13 bit field reports the size (in bytes) of the
second data buffer.
Note:
The RBS2 value must be a multiple of 4/8/16 depending on the width
of the bus otherwise the resulting behaviour is undefined.
[15]
RER
Receive End of Ring
When set, this bit indicates that the descriptor list
reached its final descriptor. The DMA returns to the base address of the list,
creating a descriptor ring.
[14]
RCH
Second Address Chained
When set, this bit indicates that the second
address in the descriptor is the Next Descriptor address rather than the
second buffer address. When this bit is set, RBS2 (RDES1[28:16]) is a "don't
care" value. RDES1[15] takes precedence over RDES1[14].
Table 418.
Receive descriptor 0 (RDES0) (continued)
Bit
Name
Description