Freescale Semiconductor MPC8260 PowerQUICC II Family Reference Manual page 1206

Fast Ethernet Controller
1
Offset Name
0xB4 CF_RANG
E
0xB6 MAX_B
0xB8 MAXD1
0xBA MAXD2
0xBC MAXD
0xBE DMA_CNT Hword Rx DMA counter. Temporary down-counter used to track the frame length.
2
0xC0 OCTC
2
0xC4 COLC
2
0xC8 BROC
2
0xCC MULC
2
0xD0 USPC
2
0xD4 FRGC
2
0xD8 OSPC
35-10
Table 35-2. Ethernet-Specific Parameter RAM (continued)
Width
Hword Control frame range. Internal usage
Hword Maximum BD byte count. Internal usage
Hword Max DMA1 length register (typically 1520 decimal). Lets the user prevent system bus
writes after a frame exceeds a specified size. The MAXD1 value is valid only if an
address match is detected. If the Ethernet controller detects an incoming Ethernet
frame larger than the user-defined value in MAXD1, the rest of the frame is discarded.
The Ethernet controller waits for the end of the frame (or until MFLR bytes have been
received) and reports the frame status and length (including the discarded bytes) in
the last RxBD. This value must be greater than 32.
Hword Max DMA2 length register (typically 1520 decimal). Lets the user prevent system bus
writes after a frame exceeds a specified size. The value of MAXD2 is valid in
promiscuous mode when no address match is detected. If the Ethernet controller
detects an incoming Ethernet frame larger than the value in MAXD2, the rest of the
frame is discarded. The Ethernet controller waits for the end of the frame (or until
MFLR bytes are received) and reports frame status and length (including the
discarded bytes) in the last RxBD. In a monitor station, MAXD2 can be much less than
MAXD1 to receive entire frames addressed to this station, but receive only the
headers of all other frames.This value must be less than MAXD1.
Hword Rx maximum DMA. Internal usage
Word (RMON mode only) The total number of octets of data (including those in bad packets)
received on the network (excluding framing bits but including FCS octets).
Word (RMON mode only) The best estimate of the total number of collisions on this Ethernet
segment.
Word (RMON mode only) The total number of good packets received that were directed to
the broadcast address. Note that this does not include multicast packets.
Word (RMON mode only) The total number of good packets received that were directed to
a multicast address. Note that this number does not include packets directed to the
broadcast address.
Word (RMON mode only) The total number of packets received that were less than 64 octets
(excluding framing bits but including FCS octets) and were otherwise well-formed.
Word (RMON mode only) The total number of packets received that were less than 64 octets
long (excluding framing bits but including FCS octets) and had either a bad FCS with
an integral number of octets (FCS error) or a bad FCS with a non-integral number of
octets (alignment error). Note that it is entirely normal for etherStatsFragments to
increment because it counts both runts (which are normal occurrences due to
collisions) and noise hits.
Word (RMON mode only) The total number of packets received that were longer than 1518
octets (excluding framing bits but including FCS octets) and were otherwise
well-formed.
MPC8260 PowerQUICC II Family Reference Manual, Rev. 2
Description
Freescale Semiconductor