Chapter 12: 10/100 IEEE802.3 Media Access Controller
TX7901 User’s Manual (Rev. 6.30T – Nov, 2001)
12-39
Word 0 Fields
Bit(s)
Field
Description
[1:0]
00 Ethernet type
01 IEEE type
10 VLAN I
11 VLAN II
14
RxBufErr
Descriptor Error
When set, indicates that a frame truncation was caused by a frame that does not fit within
the current Descriptor buffers, and that the MAC does not own the next Descriptor. The
frame is truncated.
13
RxPStop
Receive Process Stopped
When set, indicates that the reception process has been stopped.
12
RxNoBuf
Receive Buffer Unavailable
When set, indicates that the next Descriptor in the reception list is owned by the host and
cannot be acquired by the MAC. The reception process is suspended.
11
RxErr
Receive Error
When set, indicates that the macxRxEr signal on the MII is asserted while macxRxDV is
High. The presence of macxRxEr will also cause the CRC bit to be set and the Frames
Received with Bad CRC counter to be incremented.
10
RxJab
Jabber on Reception
When set, indicates that the frame received is greater than the maximum size with an
incorrect CRC.
9
RxFAErr
Frame Alignment Error
When set, indicates that the frame received has a frame alignment error. The CRC is
invalid, and the byte count is greater than or equal to 64 bytes.
8
RxCRCErr
CRC Error
When set, indicates that the frame received is greater than or equal to 64 bytes, and has
a correct CRC.
7
RxUnds
Undersized Frame
When set, indicates that the frame received is less than 64 bytes, and has a correct CRC.
6
RxFrag
Fragment
When set, indicates that the frame received is less than 64 bytes, and has an incorrect
CRC.
5
RxLongErr
Frame Long Error
When set, indicates that the frame received is greater than the maximum size with a
correct CRC.
4
RxPA
Physical Address
When set, indicates that the destination address of the received frame is a physical
address.
3
RxMA
Multicast Address
When set, indicates that the destination address of the received frame is a multicast
address.
2
RxBA
Broadcast Address
When set, indicates that the destination address of the received frame is a broadcast
address.
1
RxFOverf
FIFO Overflow
When set, indicates that the frame is not able to be stored in the RxFIFO.
0
RxGood
Received a Good Frame
When set, indicates that reception of a frame is complete. Specific frame status
information has been posted in the Descriptor
Word 1 Fields
Bit(s)
Field
Description
63:32
Buffer Address 1
This address points to buffer 1 locations. This address must be 8-byte aligned.
31:0
Buffer Address 2
This address points to buffer 2 locations. This address must be 8-byte aligned.
Summary of Contents for TMPR7901
Page 1: ...TX System RISC TX79 Family TMPR7901 Symmetric 2 way superscalar 64 bit CPU ...
Page 14: ...Handling Precautions ...
Page 15: ......
Page 17: ...1 Using Toshiba Semiconductors Safely 1 2 ...
Page 41: ...4 Precautions and Usage Considerations 4 2 ...
Page 42: ...TX7901 User s Manual Rev 6 30T November 2001 DOCUMENT NUMBER M 99 00004 07 ...
Page 43: ......
Page 259: ...Chapter 13 Removed TX7901 User s Manual Rev 6 30T Nov 2001 13 1 13 Removed ...
Page 260: ...Chapter 13 Removed TX7901 User s Manual Rev 6 30T Nov 2001 13 2 ...