參數(shù)資料
型號: IXF440
英文描述: LAN HUB CONTROLLER
中文描述: 局域網(wǎng)集線器控制器
文件頁數(shù): 48/100頁
文件大?。?/td> 1354K
代理商: IXF440
IXF440 Multiport 10/100 Mbps Ethernet Controller
48
Datasheet
4.1.2
FIFO Status Signaling
The IXF440 reports the status of each FIFO through dedicated signals. Each transmit FIFO has a
txrdy signal indicating that there is enough free space to load new data. Each receive FIFO has a
rxrdy signal indicating that there is enough data to be transferred onto the IX Bus. The txrdy signals
are driven by the IXF440 when the txctl_l signal is asserted, and the rxrdy signals are enabled by
the rxclt_l signal.The txrdy signal of a specific port is asserted when the txctl_l signal is asserted
and the specific port is selected (fps[2:0] or, alternatively, tx_fps[2:0] in Split). The same applies
for the rxrdy signal of a specific port, which is asserted with rxctl_l assertion and the specific port
selection (fps[2:0]).
4.2
Packet Transmission
The following sections describe the packet transmission policy.
4.2.1
Packet Loading
The IXF440 loads packets from the IX Bus into the transmit FIFO during burst accesses. In order
to guarantee a minimal amount of data transfer, the transmit FIFO txrdy signal reports minimal
space availability according to a programmable threshold (FFO_TSHD<TTH>).
When a new packet is loaded in the FIFO, the first cycle of the first burst must be signalled with
sop signal assertion. If the txasis signal is asserted together with sop, the packet will be sent onto
the network without padding or CRC addition. At the end of a packet load, the last data must be
signalled with the assertion of the eop signal in the last cycle of the last burst. If the txerr signal is
asserted together with eop while sending the packet onto the network, the MII error signal terr will
be asserted and the CRC will be damaged if it was requested to be appended by the IXF440.
Up to two packets can be loaded in the transmit FIFO, although the IXF440 may be programmed to
handle only a single packet at a time (TX_PARAM<SPM>).
Byte masking signals (fbe_l[7:0]) may be used to load selective bytes. They can be used during
packet transfer to load packet segments on byte boundaries and for loading the exact number of
bytes at the end of a packet. Valid bytes may start at any byte boundary, while all valid bytes in a
given cycle need to be contiguous.
For example, a packet may be built up from the following buffers, with each one being transferred
in a different burst:
Buffer 1:
Buffer 2:
B3
B11
X
B2
B10
X
B1
B9
X
X
B8
X
X
B7
X
X
B6
X
X
B5
X
X
B4
B12
X
X
X
B14
B13
X
X
X
相關(guān)PDF資料
PDF描述
IXF6048 Telecommunication IC
IXFH42N20S TRANSISTOR | MOSFET | N-CHANNEL | 200V V(BR)DSS | 42A I(D) | TO-247VAR
IXFH4N100Q TRANSISTOR | MOSFET | N-CHANNEL | 1KV V(BR)DSS | 4A I(D) | TO-247AD
IXFH50N20S TRANSISTOR | MOSFET | N-CHANNEL | 200V V(BR)DSS | 50A I(D) | TO-264AA
IXFH58N20S TRANSISTOR | MOSFET | N-CHANNEL | 200V V(BR)DSS | 58A I(D) | TO-247VAR
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
IXF-45A15AF 制造商:ILSI 制造商全稱:ILSI America LLC 功能描述:Crystal Filter 3 Lead Metal Package
IXF-45A15AT 制造商:ILSI 制造商全稱:ILSI America LLC 功能描述:Crystal Filter 3 Lead Metal Package
IXF-45A15BF 制造商:ILSI 制造商全稱:ILSI America LLC 功能描述:Crystal Filter 3 Lead Metal Package
IXF-45A15BT 制造商:ILSI 制造商全稱:ILSI America LLC 功能描述:Crystal Filter 3 Lead Metal Package
IXF-45A15CF 制造商:ILSI 制造商全稱:ILSI America LLC 功能描述:Crystal Filter 3 Lead Metal Package