參數(shù)資料
型號(hào): MC68302FC20CR2
廠商: MOTOROLA 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, PQFP132
封裝: 0.950 X 0.950 INCH, 0.025 INCH PITCH, PLASTIC, QFP-132
文件頁(yè)數(shù): 77/128頁(yè)
文件大小: 641K
代理商: MC68302FC20CR2
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)第20頁(yè)第21頁(yè)第22頁(yè)第23頁(yè)第24頁(yè)第25頁(yè)第26頁(yè)第27頁(yè)第28頁(yè)第29頁(yè)第30頁(yè)第31頁(yè)第32頁(yè)第33頁(yè)第34頁(yè)第35頁(yè)第36頁(yè)第37頁(yè)第38頁(yè)第39頁(yè)第40頁(yè)第41頁(yè)第42頁(yè)第43頁(yè)第44頁(yè)第45頁(yè)第46頁(yè)第47頁(yè)第48頁(yè)第49頁(yè)第50頁(yè)第51頁(yè)第52頁(yè)第53頁(yè)第54頁(yè)第55頁(yè)第56頁(yè)第57頁(yè)第58頁(yè)第59頁(yè)第60頁(yè)第61頁(yè)第62頁(yè)第63頁(yè)第64頁(yè)第65頁(yè)第66頁(yè)第67頁(yè)第68頁(yè)第69頁(yè)第70頁(yè)第71頁(yè)第72頁(yè)第73頁(yè)第74頁(yè)第75頁(yè)第76頁(yè)當(dāng)前第77頁(yè)第78頁(yè)第79頁(yè)第80頁(yè)第81頁(yè)第82頁(yè)第83頁(yè)第84頁(yè)第85頁(yè)第86頁(yè)第87頁(yè)第88頁(yè)第89頁(yè)第90頁(yè)第91頁(yè)第92頁(yè)第93頁(yè)第94頁(yè)第95頁(yè)第96頁(yè)第97頁(yè)第98頁(yè)第99頁(yè)第100頁(yè)第101頁(yè)第102頁(yè)第103頁(yè)第104頁(yè)第105頁(yè)第106頁(yè)第107頁(yè)第108頁(yè)第109頁(yè)第110頁(yè)第111頁(yè)第112頁(yè)第113頁(yè)第114頁(yè)第115頁(yè)第116頁(yè)第117頁(yè)第118頁(yè)第119頁(yè)第120頁(yè)第121頁(yè)第122頁(yè)第123頁(yè)第124頁(yè)第125頁(yè)第126頁(yè)第127頁(yè)第128頁(yè)
ETHERNET Controller
MOTOROLA
MC68EN302 REFERENCE MANUAL
4-13
The BDSIZE field in the EDMA register allows the user to define up to sixty-four buffers for
the transmit channel and up to one hundred twenty buffers for the receive channel. The total
number of combined transmit and receive buffers is one-hundred-twenty-eight. Each BD
table, transmit and receive, forms a circular queue with separate transmit Buffer Descriptor
and receive Buffer Descriptor pointers maintained in the hardware. The length of the circular
queues may also be controlled by using the W (wrap) bit in the buffer descriptors.
If the transmit FIFO empties of data before the end of the frame, an underrun occurs and a
bad CRC is appended to the partially transmitted data. In addition, the UN bit is set in the
last BD of the affected frame. Transmit underrun may occur if the Ethernet controller can not
access the 68000 bus or if the next BD in the frame is not available.
During the receive process, if data from a frame is available but no BD is available, the BSY
interrupt is generated, warning the user that data will soon be lost if a BD does not become
available. If the receive FIFO overruns because there is no available BD or the Ethernet
controller can not access the 68000 bus, then the last BD for the receive frame will have the
OV bit set.
4.2.1 ETHERNET RECEIVE BUFFER DESCRIPTOR (RX BD)
The user initializes the E, W, I, and (optionally) RO bits in the first word and the pointer in
3rd and 4th words of the receive buffer descriptor. The Ethernet controller writes the
following status bits:
First word: E, L, F, M, LG, NO, SH, CR, OV and CL bits. The M, LG, NO, SH, CR, OV
and CL bits in the first word of the buffer descriptor are only modified by the Ethernet
controller when the L bit is set
Second word: the buffer length
Third word: the Reason and ARIndex fields if the INDEX_EN bit in the AR_CNTRL
register is set.
Figure 4-2. Ethernet Receive Buffer Descriptor (Rx BD)
The first word of the receive buffer descriptor contains status and control information
concerning buffer descriptor handling and data flow. These status and control bits are
described in the following paragraphs.
Offset + 0
Offset + 2
Offset + 4
Offset + 6
Rx Data Buffer Pointer - A15–A0
Data Length
CL
OV
CR
SH
NO
LG
-
M
-
F
L
I
W
RO
E
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
ARIndex
Reason
A23–A16
相關(guān)PDF資料
PDF描述
MC68302FC16CR2 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP132
MC68LC302PU20CT 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP100
MC68EN302PV25BT 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP144
MC68302PV33C 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP144
SPAK302PV16VC 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP144
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MC68302FC25 制造商:MOTOROLA 制造商全稱:Motorola, Inc 功能描述:Integrated Multiprotocol Processor User’s Manual
MC68302FC25C 功能描述:IC MPU MULTI-PROTOCOL 132-PQFP 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
MC68302FE16 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Communications Controller
MC68302FE16C 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Communications Controller
MC68302FE20 制造商:未知廠家 制造商全稱:未知廠家 功能描述:Communications Controller