參數(shù)資料
型號: GT-48004A
廠商: Galileo Technology Services, LLC
英文描述: Four Port Switched Fast Ethernet Controller(四端口、交換式快速以太網(wǎng)控制器)
中文描述: 四端口交換式快速以太網(wǎng)控制器(四端口,交換式快速以太網(wǎng)控制器)
文件頁數(shù): 32/106頁
文件大?。?/td> 953K
代理商: GT-48004A
GT-48004A Four Port Switched Fast Ethernet Controller
31
Revision 1.0
N:\Marketing\Docs\Archive\48004A\DATASHEET\Rev 1.0\484ads10.fm
9.
Unicast Intervention Mode
The GT-48004A supports a powerful feature called Intervention Mode for unicast packets. Intervention in Unicast traffic
is optional per MAC address. Each entry in the Address Table includes an Intervention bit for the destination address
(bit 62) and the source address. When an Intervention mode bit is set, the GT-48004A will
not forward the packet auto-
matically to the destination device. Instead, the GalNet device will send a BUFFER_REQUEST message (Section
11.3.3) to CPU memory. The BUFFER_REQUEST messages will be sent to the buffer area in the CPU main memory
which contains 256 entries of dual 32-bit words. The location of this CPU memory is specified by the CPU Intervention
Base Address at 0x140048. The buffer area is pointed to by this Base Address register and a Shadow register at this
same offset. The BUFFER_REQUEST message includes information about the routing of the packet (Source and Tar-
get port/device numbers). The CPU then has the option to:
discard the packet
forward the packet to a specific device
request the packet be transferred to CPU buffer memory
Figure 7 shows a Unicast packet transfer using Intervention mode.
Figure 7: Unicast Packet Transfer With Intervention
The sequence illustrated is as follows:
1.
The incoming packet is fed to the Rx FIFO and transferred to an empty block in the Receive Buffer area of DRAM.
2.
If a corresponding Intervention bits is set, the device sends a BUFFER_REQUEST message (Section 11.3.3) to
the CPU’s Intervention Base Address. The BUFFER_REQUEST includes the source port and the source buffer
address
The CPU then has the following options:
1.
Discard the packet.
The CPU sends a START_OF_PACKET message (Section 11.3.6) to the source device with the Byte Count
field cleared with all 0s (arrow #3).
2.
Forward the Packet to a port in the same device
CPU
PCI BUS
GT-48004A
DRAM
GT-48004A
DRAM
1
23
5
6
4
7
DRAM
Messages
Packets
相關(guān)PDF資料
PDF描述
GT-48006A Low Cost Two Port 10/100Mbps Ethernet Bridge/Switch Controller(低成本、雙端口10/100Mbps以太網(wǎng)橋式/交換式控制器)
GT-48207 Advanced Switched Ethernet Controllers for 10+10/100 BaseX(高級交換式 10+10/100 BaseX以太網(wǎng)控制器)
GT-48208 Advanced Switched Ethernet Controllers for 10+10/100 BaseX(高級交換式 10+10/100 BaseX以太網(wǎng)控制器)
GT-48212 Advanced Switched Ethernet Controllers for 10+10/100 BaseX(高級交換式 10+10/100 BaseX以太網(wǎng)控制器)
GT-64010A System Controller with PCI Interface for R4XXX/ R5000 Family CPUs(帶PCI接口用于R4XXX/ R5000 系列 CPUs的系統(tǒng)控制器)
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
GT482 制造商:CORNELL DUBILIER ELECTRONICS 功能描述:Cap Ceramic 82pF 3000V SL 5% (12 X 6mm) Radial 9.5mm 85°C
GT48212-A6-PBB1C000 制造商:Marvell 功能描述:
GT48212-A6-PBB-C000 制造商:Marvell 功能描述:12 PORT E + 2 PORT FE SWITCH (MANAGED) - Trays
GT48300-A1-BBE1C083 制造商:Marvell 功能描述:Marvell GT48300-A1-BBE1C083
GT48300-A1-BBE-C000 制造商:Marvell 功能描述:Marvell GT48300-A1-BBE-C000