MDS212 Datasheet, PDF (77/111 Pages) Zarlink Semiconductor Inc – 12-Port 10/100Mbps Ethernet Switch

MDS212
Data Sheet
18.2.4.3 BCT - (FCB) Buffer Counter Threshold
• Access
• Address:
Non-Zero-Wait-State Direct-Access
h74C
31
19
10 9
Hi Limit
Write/Read
0
Low Limit
Bit[9:0]
Bit[19:10
Low_Limit
HI_Limit
Low limit number of frames to each destination port (i.e., Source
port limits the # of FCB used by each destination port)
High limit number of frames to each destination port (i.e.,
Source port limits the # of FCB used by each destination port)
18.2.4.4 BCHL - Buffer Counter Hi-low Selection
• Access
• Address:
Non-Zero-Wait-State Direct-Access
h750
Write/Read
31
25 24
13 12 11
0
Rp_Hi_Low Sel
Lp_Hi_Low Sel
Bit[11:0]
Bit[12]
Bit[24:13]
Bit[31:25]
Lp_Hi_Low Sel
Reserved
Rp_Hi_Low Sel
Reserved
Selection for Low or High Limit of Buffer Counter for Local
device 12 bits maps to 12 ports in Local Device
1 = select hi limit
0 = select low limit
Selection for Low or High Limit of Buffer Counter for Remote
device 13 bits maps to 13 ports in Remote Device
1 = select hi limit
0 = select low limit
18.2.5 Queue Management Register
18.2.5.1 CINQ - CPU Input Queue
• Access:
• Address:
Non-Zero-Wait-State, Direct Access,
h708
Write only
31
0
32-bit data from CPU input queue
Note: Check IQ_RDY=1 in DCR3 (Interface Status Register) before writing into CPU Input Queue.
18.2.5.2 COTQ - CPU Output Queue
• Access:
• Address:
Non-Zero-Wait-State, Direct Access,
h70C
Read only
31 30
0
CPU Output Queue Entry
Bit [30:0]
Bit [31]
31-bit CPU Output Queue Entry
Status queue is ready
77
Zarlink Semiconductor Inc.