参数资料
型号: MC68LC302PU25CT
厂商: FREESCALE SEMICONDUCTOR INC
元件分类: 微控制器/微处理器
英文描述: 4 CHANNEL(S), 10M bps, LOCAL AREA NETWORK CONTROLLER, PQFP100
封装: 14 X 14 MM, 1.40 MM HEIGHT, 0.50 MM PITCH, PLASITC, LQFP-100
文件页数: 77/128页
文件大小: 641K
代理商: MC68LC302PU25CT
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
相关PDF资料
PDF描述
MC908AB32VFUR2 8-BIT, FLASH, 8.4 MHz, MICROCONTROLLER, PQFP64
MC908AZ60AVFUR2 8-BIT, FLASH, 8.4 MHz, MICROCONTROLLER, PQFP64
MC912D60ACFU8 16-BIT, FLASH, 8 MHz, MICROCONTROLLER, PQFP80
MCHC908JK3CDWR2 8-BIT, FLASH, 4 MHz, MICROCONTROLLER, PDSO20
MPC563MZP66R2 32-BIT, FLASH, 66 MHz, RISC MICROCONTROLLER, PBGA388
相关代理商/技术参数
参数描述
MC68LK332ACAG16 功能描述:32位微控制器 - MCU 32BIT MCU 2KRAM TPU QSM RoHS:否 制造商:Texas Instruments 核心:C28x 处理器系列:TMS320F28x 数据总线宽度:32 bit 最大时钟频率:90 MHz 程序存储器大小:64 KB 数据 RAM 大小:26 KB 片上 ADC:Yes 工作电源电压:2.97 V to 3.63 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:LQFP-80 安装风格:SMD/SMT
MC68LK332ACAG16 制造商:Freescale Semiconductor 功能描述:Microcontroller
MC68LK332ACEH16 功能描述:32位微控制器 - MCU 32BIT MCU 2KRAM TPU QSM RoHS:否 制造商:Texas Instruments 核心:C28x 处理器系列:TMS320F28x 数据总线宽度:32 bit 最大时钟频率:90 MHz 程序存储器大小:64 KB 数据 RAM 大小:26 KB 片上 ADC:Yes 工作电源电压:2.97 V to 3.63 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:LQFP-80 安装风格:SMD/SMT
MC68LK332ACPV16 功能描述:IC MCU 32BIT LV AMASK 144-LQFP RoHS:否 类别:集成电路 (IC) >> 嵌入式 - 微控制器, 系列:M683xx 其它有关文件:STM32F101T8 View All Specifications 特色产品:STM32 32-bit Cortex MCUs 标准包装:490 系列:STM32 F1 核心处理器:ARM? Cortex?-M3 芯体尺寸:32-位 速度:36MHz 连通性:I²C,IrDA,LIN,SPI,UART/USART 外围设备:DMA,PDR,POR,PVD,PWM,温度传感器,WDT 输入/输出数:26 程序存储器容量:64KB(64K x 8) 程序存储器类型:闪存 EEPROM 大小:- RAM 容量:10K x 8 电压 - 电源 (Vcc/Vdd):2 V ~ 3.6 V 数据转换器:A/D 10x12b 振荡器型:内部 工作温度:-40°C ~ 85°C 封装/外壳:36-VFQFN,36-VFQFPN 包装:托盘 配用:497-10030-ND - STARTER KIT FOR STM32497-8853-ND - BOARD DEMO STM32 UNIV USB-UUSCIKSDKSTM32-PL-ND - KIT IAR KICKSTART STM32 CORTEXM3497-8512-ND - KIT STARTER FOR STM32F10XE MCU497-8505-ND - KIT STARTER FOR STM32F10XE MCU497-8304-ND - KIT STM32 MOTOR DRIVER BLDC497-6438-ND - BOARD EVALUTION FOR STM32 512K497-6289-ND - KIT PERFORMANCE STICK FOR STM32MCBSTM32UME-ND - BOARD EVAL MCBSTM32 + ULINK-MEMCBSTM32U-ND - BOARD EVAL MCBSTM32 + ULINK2更多... 其它名称:497-9032STM32F101T8U6-ND
MC68LK332GCAG16 功能描述:32位微控制器 - MCU 32BIT MCU 2KRAM TPU QSM RoHS:否 制造商:Texas Instruments 核心:C28x 处理器系列:TMS320F28x 数据总线宽度:32 bit 最大时钟频率:90 MHz 程序存储器大小:64 KB 数据 RAM 大小:26 KB 片上 ADC:Yes 工作电源电压:2.97 V to 3.63 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:LQFP-80 安装风格:SMD/SMT