EZ80F91MCU ZILOG [Zilog, Inc.], EZ80F91MCU Datasheet - Page 266

• Manufacturer Part Number: EZ80F91MCU
• Description: eZ80Acclaim-TM Flash Microcontrollers
• Manufacturer: ZILOG [Zilog, Inc.]

Table 134. Transmit Descriptor Status
Table 135. Receive Descriptor Status
PS019209-0504
Bit
12
11
10
9
8
7
6
5
4
[3:0] TxNumberOfCollisions
Bit
15
14
13
12
11
10
Name
TxHuge
TxLOOR
TxLCError
TxCrcError
TxPktDeferred
TxXsDfr
TxFifoUnderRun
TxLateCol
TxMaxCol
Name
RxOK
RxAlignError
RxCrcError
RxLongEvent
RxPCF
RxCF
Description
1 = Packet size is very large (Pkt_Size > EmacMaxf).
1 = Type/Length field is out of range (larger than 1518 bytes).
1 = Type/Length field is not a Type field and it does not match the
actual data byte length of the Ethernet packet. The data byte length is
the number of bytes of data in the Ethernet packet between the Type/
Length field and the FCS.
1 = The packet contains an invalid FCS (CRC). This flag is set when
CRCEN = 0 and the last 4 bytes of the packet are not the valid FCS.
1 = Packet is deferred.
1 = Packet is excessively deferred. (> 6071 nibble times in 100 BaseT
or 24,287 bit times in 10 BaseT).
1 = TxFIFO experiences Underrun. Check the TxAbort bit to see if the
packet is aborted or retried.
1 = A late collision occurs. Collision is detected at a byte count >
EmacCfg2[5:0]. Collisions detected before the byte count reaches
EmacCfg2[5:0] are early collisions and retried.
1 = The maximum number of collisions occurs. # Collisions >
EmacCfg3[3:0]. These packets are aborted.
This field contains the number of collisions that occur while
transmitting the packet.
Description
1 = Packet received intact.
1 = An odd number of nibbles is received.
1 = The CRC (FCS) is in error.
1 = A Long or Dropped Event occurs. A Long Event is when a packet
over 50,000 bit times occurs. A Dropped Packet can occur if the
minimum interpacket gap is not met, the preamble is not pure, and the
EmacCfg3[PUREP] bit is set, or if a preamble over 11 bytes in length
is detected and the EmacCfg3[LONGP] bit is set to 1.
1 = The packet is a pause control frame.
1 = The packet is a control frame.
P R E L I M I N A R Y
Ethernet Media Access Controller
Product Specification
eZ80F91 MCU
247