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RISC Microcode from RAM
C-8
MC68360 USER’S MANUAL
End Delimiter (ED) generation/checking
Init Rx/Tx, Stop TX, Restart TX and Enter Hunt Mode Commands
Token Rotation Timer, Idle Timer, Slot Timer and Time-out Timer
Consumes 1280 bytes of the QUICC’s internal memory.
C.6 ENHANCED ETHERNET FILTERING
The enhanced Ethernet filtering microcode has been created to add a bit more flexibility to
the current Ethernet Controller. It allows the user to perfectly accept or reject frames with
destination addresses that are contained in a table of 24 entries. In addition to the filtering
capability, the microcode adds the ability to replace the externally sampled tag byte with one
that is extracted from the address table.
C.6.1 Key Features
Can accept or reject incoming frames if the destination MAC address is contained in a
list of 24 preprogrammed entries.
Allows a shorter list to obtain better peripheral performance.
Can optionally tag incoming accepted frames with an 8-bit tag appended to the end of
the frame (rather than using a CAM).
The filtering can be turned off to allow tagging with no frame rejection.
Can filter on group and individual addresses.
Is a “small” microcode (consumes 768 bytes of DPRAM).
Filtering is only supported on one Ethernet channel (SCC1), the other channel operates
normally.
C.6.2 Performance
The overhead incurred by the filtering algorithm will depend upon the number of entries in
the address table. Table C-5 shows possible configurations of other channels given the load
added by a number of entries in the address table.
Table C-5. Channel Configuration
Number of addresses
Possible Configuration of Other Channels
1-8
1 x 10 Mbit Ethernet, 1 x 200 Kbit HDLC
9-16
1 x 10 Mbit Ethernet, 1 x 200 Kbit HDLC
17-24
1 x 10 Mbit Ethernet
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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