MDS212 Datasheet, PDF (92/111 Pages) Zarlink Semiconductor Inc – 12-Port 10/100Mbps Ethernet Switch

MDS212
Data Sheet
31
30
H_RDY
Bit [9:0]
Bit [30:10]
Bit [31]
10 9
0
FCB_Handle [11:0]
FCB_HANDLE
Reserved
H_RDY
FCB Handle Address
FCB Handle Ready
0=Not Ready 1=Ready
18.2.11.7 CPU Access Internal RAMs (Tables)
Usage: (refer to section 9.0 “The High Density Instruction Set Computer (HISC)” on page 37 for details)
• The CPU uses the following methods to access the five internal RAMs, including MCID, VLAN port mapping
(VMAP), BM control Table (BMCT), FCB and Transmission Queue control (QCNT).
• Registers:
• CPUIRCMD:
Command register
• CPUIRDAT0:
Data Register for specific entry of content Bit[31:0]
• CPUIRDAT1:
Data Register for specific entry of content Bit[63:32]
• CPUIRDAT2:
Data Register for specific entry of content Bit[95 64]
• CPUIRRDY:
Data Read Ready.
• CPU Reads FCB
• CPU write the read command into CPUIRCMD with FCB Handle, W/R=0. And set C_RDY. Also, set
the table type = FCB, (CPUIRCMD[14]=1)
• Frame Engine puts the specified FCB content into CPUIRDATL and CPUIRDATM
• Frame Engine Clear C_RDY
• Frame Engine set CPUIRRDY[0] to notify CPU that the FCB data is ready to be read.
• CPU writes FCB
• CPU writes the content of FCB into CPUIRDATL and CPUIRDATM
• CPU writes the handle of FCB into CPUIRCMD [9:0], set CPUIRCMD [10] = 1,(write CMD),
set CPUIRCMD[31]=1, CMD_RDY and set the Table Index to FCB, (CPUIRCMD[14]=1).
• Frame Engine clears CPUIRCMD [31], C_RDY, when Frame Engine reads FCB done
• Apply the similar method to access the other four tables.
18.2.11.8 CPUIRCMD - CPU Internal RAM Command Register
• Access:
Non-Zero-Wait-State,Direct Access,Write/Read
• Address: h584
• Command for CPU accesses five internal Tables
31
30
C_RDY
Bit [9:0]
Bit [10]
16
15
14
13
12
11
10 9
0
QCNT FCB BMCT VMAP MCID W/R
Entry Index [9:0]
Entry Index
Type = MCID(16)
Type = VMAP(256)
Type = BMCT(1K)
Type = FCB(1K)
Type = QCNT (64)
W/R
The index of specified entry
Entry index[3:0]
Entry index[7:0]
Entry index[9:0]
Entry index[9:0]
Entry index[5:0]
Write or Read the table entry
0=Read 1=Write
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