The invention discloses a direct memory access device, comprising bus Slave interface, DMA request and response interface, bus Master interface, control logic and register set, channel logic and register set, and interrupt request logic, where the key point is that control logic of each DMA channel in the channel logic and register set comprises: channel control logic used to control state switching of first and second state selection units and control read-in/-out of data from source address to destination address; first and second data buffer areas for storing data read in DMA channels in different directions; first and second state selection units for reading data from the source address into the first or second data buffer area and sending data in the second or first data buffer area to the destination address.
本发明公开了一种直接存储器存取装置，包括总线Slave接口、DMA请求和响应接口、总线Master接口、控制逻辑和寄存器组、通道逻辑和寄存器组、中断请求逻辑，关键是，通道逻辑和寄存器组中每个DMA通道的控制逻辑包括：通道控制逻辑，用于控制第一和第二状态选择单元的状态切换，并控制数据从源地址到DMA通道到目的地址的读入和读出；第一和第二数据缓冲区，存储不同方向读入DMA通道的数据；第一和第二状态选择单元，将来自源地址的数据读入第一或第二数据缓冲区，并将第二或第一数据缓冲区的数据发往目的地址。
The BLOK pin will be asserted to indicate that the read and write should be treated as an atomic operation on the bus.
通过对BLOK针进行assert来决定此次对总线的读取和写入是否为原子操作。
Excuse me. I read in your travel brochure about your bus tours to Niagara Falls.
请问一下，我从你们的旅游手册里看到有关尼加拉瓜瀑布巴士旅游的资料。
When the READ signal is asserted, the memory subsystem places the instruction code to be fetched onto the computer system's data bus, The microprocessor then inputs this data from the bus and stores it in one of its internal registers.
读信号发出后，存储器子系统就把要取的指令码放到计算机的数据总线上，微处理器就从数据总线上输入该数据并且将它存储在其内部的某个寄存器中。
3 Instruction Cycle When the READ signal is asserted, the memory subsystem places the instruction code to be fetched onto the computer system's data bus, The microprocessor then inputs this data from the bus and stores it in one of its internal registers.
读信号发出后，读信号发出后，存储器子系统就把要取的指令码放到计算机的数据总线上，微处理器就从数据总线上输入该数据并且将它存储在其内部的某个寄存器中。
54 Chapter 1 The History and Future of Computers 2.1.2 Instruction Cycle When the READ signal is asserted, the memory subsystem places the instruction code to be fetched onto the computer system's data bus, The microprocessor then inputs this data from the bus and stores it in one of its internal registers.
读信号发出后，存储器子系统就把要取的指令码放到计算机的数据总线上，微处理器就从数据总线上输入该数据并且将它存储在其内部的某个寄存器中。
14 Chapter 2 Organization of Computers 2.1.2 Instruction Cycle When the READ signal is asserted, the memory subsystem places the instruction code to be fetched onto the computer system's data bus, The microprocessor then inputs this data from the bus and stores it in one of its internal registers.
读信号发出后，读信号发出后，存储器子系统就把要取的指令码放到计算机的数据总线上，微处理器就从数据总线上输入该数据并且将它存数据总线上，储在其内部的某个寄存器中。至此，微处理器已经取得了指令。
The first would send a message on the bus requesting to read the status of the device's ready flag.
第一条指令，将在数据传输总线上发送一条请求读取设备就绪标记状态的通讯。
System clock generator and timing control circuit, CPU and bus control logic, DMA transfers and interrupt control, memory and control logic to read and write, the system configuration parameters and to read and write memory, keyboard control logic, I/O bus slot control logic and even some peripherals are integrated on the motherboard.
系统时钟发生器与时序控制电路、CPU 及总线控制逻辑、DMA 传输与中断控制、内存及其读写控制逻辑、系统配置参数的存储与读写、键盘控制逻辑、I/O 总线插槽甚至某些外设控制逻辑均集成在主板上。
It integrates the above system clock generator, clock circuit, CPU and bus control logic, DMA transfers and interrupt control, memory and control logic to read and write system memory configuration parameters and to read and write, the keyboard control logic, I/O Bus slot control logic and even some peripherals.
它上面集成了系统时钟发生器、时钟电路、CPU及总线控制逻辑、DMA传输与中断控制、内存及其读写控制逻辑系统配置参数的存储与读写、键盘控制逻辑、I／O总线插槽甚至某些外设控制逻辑。
The present invention has battery to provide the system with electric energy via a switching power module, a triphase voltage type frequency converter to constitute a DC/AC converter circuit, a gate signal isolating driver circuit to generate frequency variable AC voltage driving a triphase squirrel cage motor; a signal A/D detection interface circuit module including the feedback inputs of triphase current signal, DC voltage signal, frequency converter temperature signal, pedal accelerator signal, etc.; the DSP to read and judge the I/O signal from the driver controller for corresponding treatment and operation and to read the feedback signal for vector control or direct torsion control; and a communication module for real-time control via serial port or CAN bus.
本发明涉及一种基于DSP的嵌入式电动汽车变频控制方法及装置，本发明的电池组通过开关电源模块提供系统电能，三相电压型变频器构成直交转换电路，通过门极信号隔离驱动电路产生变频交流电压驱动三相鼠笼电机；信号A/D检测接口电路模块包括三相电流信号、直流电压信号、变频器温度信号及踏板油门信号等反馈输入；DSP通过对驾驶控制器输入输出信号的读取和判断，进行相应处理和操作，通过对反馈信号的读取实现矢量控制或直接转矩控制；通讯模块通过串口或CAN总线将系统故障信息和运行状态以协议形式传送给上位机，实现实时监控。
For instruction address bus, T0 with DAT is proposed to handle both consecutive addresses and the branch target addresses; for data address bus, combination of T0 and BI method, variable-stride, and SRWEC (Separated Read/Write Encoding Contents) is proposed to handle both the randomness and continuities of data address sequence; as for instruction/data mixed address bus, DAT is used for instruction address sequence and Stride-Table which can take use of the relationship between instruction address and data address is applied for data address sequence.
对於指令位址汇流排，设计了DAT与T0搭配，以同时处理连续位址以及branch指令造成的不连续位址；对於资料位址汇流排，设计了一方法，其中结合T0与BI、动态改变位址跨距，以及区别读/写位址分别编码，可因应资料位址中连续位址与不连续位址混杂的特性来做处理；对於混和指令/资料位址汇流排，利用了指令记忆体位址与资料记忆体位址之间的关系，设计了Stride Table方法，并与DAT搭配，作为此环境的编码设计。
We must not forget the man who comes into a bus or subway car and sits down next to you, just as close as you will let him. You are reading the newspaper and he leans over and stretches his rock so that he can read the paper with you.
我们也一定不能忘掉那个冲进巴士或者地铁紧坐在你身边的人，近得就刚好是你容忍的底线，你在看报纸，然后他倾靠过来伸长脖子以便于他可以和你一起阅读。
The circuit comprises a comparison circuit, a negation gate and a first coincidence gate, wherein the comparison circuit is used to output read screen signals of a storage unit corresponding with bus signals of a second port address, the negation gate is used to inverse the read screen signals of the storage unit which are corresponding with the bus signals of the second port address, one input end of the first coincidence gate receives the read screen signals of the storage unit which are corresponding with the bus signals of the second port address after being inversed, the other input end of the first coincidence gate receives the read enable signals of a second port, and the output end of the first coincidence gate is connected with the read enable end of the second port.
所述电路包括：比较电路，用于输出第二端口地址总线信号对应的存储单元读屏蔽信号；非门，用于对第二端口地址总线信号对应的存储单元读屏蔽信号进行非运算；第一与门，第一与门的一路输入端接收非运算后的第二端口地址总线信号对应的存储单元读屏蔽信号，第一与门的另一路输入端接收第二端口的读使能信号，第一与门的输出端连接第二端口的读使能端。
The first read maps to the upper byte of the data read with 16-bit host bus and the second read maps to the lower byte.
第一次是用16位的主线读取对应的高位数据，第二次来读取相应的低位数据。
Figure 2-8. The flow of a read request for a device on a secondary bus.
图2-8。在一个二级总线上对于一个设备的读请求的流程。
According to the staff of bus companies, will be inserted U disk recorder car in traffic data collection, and then the computer will read out the data, so that drivers know the speed of each section.
据公交公司工作人员介绍，将U盘插入车上的行车记录仪里采集数据，再用电脑将数据读出来，这样就可以知道驾驶员在每个路段的行驶速度。
When the processor wants to read the contents of a memory location or register within a particular peripheral, it sets the address bus
当一个处理器想去写某一特定外设中的存储器地址或寄存器中的内容时，处理器设置地址总线并在数据总线上接收内容。
When the processor wants to read the contents of a memory location or register within a particular peripheral, it sets the address bus pins appropriately and receives the contents on the data bus.
当一个处理器想去写某一特定外设中的存储器地址或寄存器中的内容时，处理器设置地址总线并在数据总线上接收内容。
When the processor wants to read the con tents of a memory location or register within a particular peripheral, it sets the address bus pins appropriately and receives the contents on t he data bus.
当一个处理器想去写某一特定外设中的存储器地址或寄存器中的内容时，处理器设置地址总线并在数据总线上接收内容。