DS_8430_001
78Q8430 Data Sheet
Hex
Value Value
Binary
Name
Action Taken
0x14
10100b
THXA
The high-order nibble of the classification result is assigned the value of
the high-order nibble value of ‘X’.
0x15
0x16
0x17
0x18
10101b
10110b
10111b
11000b
SETMC Mark the frame as multicast for Rx statistics purposes.
VLAN Mark the frame as VLAN tagged for length checking and statistics.
SETBC Mark the frame as broadcast for Rx statistics purposes.
TOC
The control logic counter value is initialized to the value contained in the
Byte Offset field. No offset is applied.
0x1A
0x1B
11010b
11011b
DEC
The control logic counter value is decremented. If the counter has
reached zero then the control logic will decrement the previous hit value
used to generate the next CAM reference word by one.
MCTL
TDPH
Classify the frame as a MAC control frame. This also sets the Len/Type
LSB.
0x1C
0x1D
0x1E
0x1F
11100b
11101b
11110b
11111b
The pause counter most significant byte is set from the frame data.
TDLTH The Len/Type most significant byte is set from the frame data.
TDPL
The pause counter least significant byte is set from the frame data.
The Len/Type least significant byte is set from the frame data.
TDLTL
RCR Match Control
The value of the Match Control field will determine how the control logic generates the next CAM
reference word.
Table 27: RCR Match Control
Value
Name
Action Taken
00b
DONE
No more CAM reference words are generated. No further classification is
done for the current frame.
10b
01b
MD
MX
The next frame data is used to generate the next CAM reference word.
The ‘X’ value is used in place of the frame data to generate the next CAM
reference word.
11b
DROP
Drop the frame. If this is executed within the first 128 bytes of the frame
then the entire frame is dropped from the QUE. No more CAM reference
words are generated.
6.7.3 Frame Format
The following table shows the format of an Ethernet frame. The fields are in the order that the
classification engine sees them, from left to right. The byte count for each field is specified on the bottom
row of the table.
Table 28: Ethernet Frame for Classification
Destination
Address
Source
Address
Len/Typ
Hi Lo
1B 1B
LLC Data
User Pad
0-1500B 46-0B
CRC (FCS)
MSB
LSB
6 Bytes
6 Bytes
4 Bytes
If the Len/Type field contains a 16-bit value that is less than 0x0600, the field is interpreted as a length
field that specifies the number of bytes in the User field. If the value is greater than or equal to 0x0600,
the type interpretation is to be used.
6.7.4
Default CAM Rule Summary
This section provides the default rules that the 78Q8430B CAM is loaded with on reset.
Rev. 1.2
39
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
