參數(shù)資料
型號： M68LC302CPU16VCT
廠商： FREESCALE SEMICONDUCTOR INC
元件分類： 微控制器/微處理器
英文描述： 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP100
封裝： 14 X 14 MM, 1.40 MM HEIGHT, 0.50 MM PITCH, PLASITC, LQFP-100
文件頁數(shù)： 84/128頁
文件大小： 641K
代理商： M68LC302CPU16VCT
ETHERNET Controller
4-20
MC68EN302 REFERENCE MANUAL
MOTOROLA
The transmit FIFO control logic provides a signal indicating data is available to the Ethernet
transmit protocol machine. If underflow occurs, the Ethernet transmit protocol machine will
handle aborting the frame (append a bad CRC) and flushing the remainder of the frame from
the FIFO.
If a collision occurs within the slot time in a transmit frame, the FIFO supports retry by
maintaining a separate start of frame pointer (read lag pointer). New data is never written on
top of start of frame data until the slot time has passed. Two control signals pass between
the Ethernet transmit logic and the transmit FIFO to indicate when the slot time (collision
window) has been passed (Transmit Accept) or when a collision retry must take place
(Transmit Retry).
4.4.2 RECEIVE FIFO
The receive FIFO control logic provides “data available” and “receive FIFO empty” flow
control signals to the receive DMA controller. The “data available” signal is asserted as a
function of the number of bytes available in the FIFO and the WMRK bits from the EDMA
register. If overflow occurs, the STATUS word will have the OU bit set which will be written
into the receive BD. The frame should be discarded by software.
Data is written into the receive FIFO by the Ethernet receive logic in the case of status
information, and by the address recognition logic if the Reason and ARIndex fields are
enabled.
The receive FIFO control logic maintains a “start of frame” pointer that allows purging
collision fragments from the FIFO so that they need not be DMA’d. This purging of fragments
(runt frames less than 64 bytes long) is automatic and cannot be disabled.
4.5 ETHERNET PROTOCOL LOGIC
This block implements the MAC (media access control) sublayer of the IEEE 802.3
standard, supporting operation up to 10 Mbps compliant with both Ethernet and 802.3
standards. This logic is subdivided into transmit, receive and loopback/serial interface
sections.
4.5.1 ETHERNET TRANSMIT
The Ethernet transmiter block performs the following functions:
Parallel to serial conversion of data
Encapsulation of transmit frames
— Generation of preamble (PA) and start of frame delimiter (SFD)
— Transmits serial data from the transmit FIFO interface
— Pads short frames (with 0’s)
— Appends CRC, if required
— Appends bad CRC if required
— Appends JAM pattern (all 1’s)
Transmit Protocol
相關(guān)PDF資料
PDF描述
MC68LC302PU20VCT 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP100
MC68302CPV16VC 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP144
MC68LC302PU20VCT 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP100
MC68EN302CPV20BT 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP144
MC68302FC20CR2 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP132
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
M68LC302CPU20VCT 功能描述:IC MPU NETWORK 20MHZ 100-LQFP RoHS:否 類別:集成電路 (IC) >> 嵌入式 - 微處理器 系列:M683xx 標(biāo)準(zhǔn)包裝:2 系列:MPC8xx 處理器類型:32-位 MPC8xx PowerQUICC 特點(diǎn):- 速度:133MHz 電壓:3.3V 安裝類型:表面貼裝 封裝/外殼:357-BBGA 供應(yīng)商設(shè)備封裝:357-PBGA（25x25） 包裝:托盤
M68LGL061X 制造商:Panasonic Industrial Company 功能描述:SUB ONLY CRT
M68LGL061XA 制造商:Panasonic Industrial Company 功能描述:CRT OR M68LGL061X
M68LNK161X 制造商:Panasonic Industrial Company 功能描述:CRT
M68LUQ085X 制造商:Panasonic Industrial Company 功能描述:CRT
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。

采購需求

(若只采購一條型號，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進(jìn)入我的后臺，查看報價

發(fā)布成功！您可以繼續(xù)發(fā)布采購。也可以進(jìn)入我的后臺，查看報價

*型號 *數(shù)量 廠商 批號 封裝
添加更多采購

我的聯(lián)系方式

*
*
*