MDS212 Datasheet, PDF (76/111 Pages) Zarlink Semiconductor Inc – 12-Port 10/100Mbps Ethernet Switch

MDS212
18.2.3.8 Reserve Register 1
• Access
• Address:
Non-Zero-Wait-State Direct-Access Write/Read
h7B8
31
16 15
0
0x0001
0x0008
Must be set to “0X00010008”
18.2.3.9 Reserve Register 2
• Access
• Address:
Non-Zero-Wait-State Direct-Access
h7BC
Write/Read
Data Sheet
31
25
16 15
0
0x0001
0x0000
Must be set to “0X00010000”
18.2.4 Frame Control Buffers Management Register
18.2.4.1 FCBSL - FCB Queue
• Access:
• Address:
Non-Zero-Wait-State, Direct Access,
h740
Write/Read
31
18 17 16
11 10 9
0
Aging Timer Base
Max # pf FCB Buffer
Bit [10:0]
Bit [17:11]
Aging Timer Base
Defines Max # of FCB Buffers
Size Range: 1 entry, to 1024 entries
Defines the time interval between scanning of FCB Buffers for
aged buffers
Aging Time = (Number of valid FCB Buffers* Aging Timer Base)
msec
18.2.4.2 FCBST - FCB QUEUE - Buffer Low Threshold
• Access:
• Address:
Non-Zero-Wait-State, Direct Access,
h744
31
23
16 15
Write/Read
11
765
0
BLowTH
Bit [5:0]
Bit [31:6]
Buf_Low_Th
Reserved
Buffer Low Threshold – The number of frame control buffer
handles left in the Queue to be considered as running low and
trigger the interrupt to the CPU.
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Zarlink Semiconductor Inc.