AB模块1769-OF4CI原装质保供应
¥2000.00
AB模块1769-IF4I原装质保供应
¥2000.00
价格美丽1763-L16BWA/B供应充足
¥1900.00
价格美丽1769-IF16C供应充足
¥1900.00
深圳长欣是一家专注于电气工程和工业自动化的备件批发商。深圳长欣与众多制造商合作，专注于提供零部件，原始设备制造商，面板制造商，行业和终用户的停产部件解决方案
在B-to-B电气产品拥有市场，在其广的市场中为客户提供帮助
通过遍布65个5大洲的密集网络，开发了停产部件解决方案，致力于将值的工业备件以及服务更贴近客户
我们很自豪成为工业零部件标准制定者
ABB信号处理板PFSK162 3BSE015088R1应用DSP数字共享通讯导入模块DSP的性能受其对存储器子系统的管理能力的影响。如前所述，MAC和其它一些信号处理功能是DSP器件信号处理的基本能力，快速MAC执行能力要求在每个指令周期从存储器读取一个指令字和两个数据字。有多种方法实现这种读取。比如，使用多接口存储器（允许在每个指令周期内对存储器多次访问）、分离指令和数据存储器（“哈佛”结构及其派生类）以及指令缓存（允许从缓存读取指令而不是存储器，从而将存储器空闲出来用作数据读取）。另外要注意所支持的存储器空间的大小。许多DSP的主要目标市场是嵌入式应用系统，在这种应用中存储器一般较小，所以这种DSP器件具有小到中等片上存储器（4K到64K字左右），备有窄的外部数据总线。另外，绝大多数DSP的地址总线小于或等于16位，因而可外接的存储器空间受到限制。一些浮点DSP的片上存储器很小，甚至没有，但外部数据总线宽。例如TI公司的TMS320C30只有6K片上存储器，外部总线为24位，13位外部地址总线。ABB信号处理板PFSK162 3BSE015088R1应用DSP数字共享通讯导入模块而ADI的ADSP2-21060具有4Mb的片上存储器，可以多种方式划分为程序存储器和数据存储器。
选择DSP时，需要根据具体应用对存储空间大小以及对外部总线的要求来选择。
ABB信号处理板PFSK162 3BSE015088R1应用DSP数字共享通讯导入模块类型特点
DSP处理器和诸如英特尔、奔腾或Power
PC的通用处理器（GPPs）有很大的区别，这些区别产生于DSPs的结构和指令是针对信号处理而设计和开发的，它具有以下特点。
硬件乘法累加操作（MACs）为了有效完成诸如信号滤波的乘法累加运算，处理器必需进行乘法操作。GPPs起初并不是为繁重的乘法操作设计的，把DSPs同早期的GPPs区别开来的重大技术改进就是添加了能够进行单周期乘法操作的硬件和明确的MAC指令
PFSK162 3BSE015088R1Traditional GPPs use Von Norman storage structure. In this structure, one storage space is connected to the processor core through two buses (one address bus and one data bus). This structure cannot meet the requirement that MAC must access the memory four times in one instruction cycle. DSPs generally use the Harvard structure. In the Harvard structure, there are two storage spaces: program storage space and data storage space. The processor core is connected to these memory spaces through two sets of buses, allowing two accesses to the memory at the same time. This arrangement doubles the bandwidth of the processor. In the Harvard architecture, sometimes a second data storage space and bus are added to achieve greater storage bandwidth. Modern high-performance GPPs usually have two on-chip super cache memories, PFSK162 3BSE015088R1one for storing data and one for storing instructions. Theoretically, this dual on-chip cache and bus connection are equivalent to the Harvard architecture. However, GPPs use control logic to determine which data and instruction words reside in the on-chip cache. This process is usually not seen by programmers. In DSPs, PFSK162 3BSE015088R1programmers can clearly control which data and instructions are stored in the on-chip storage unit or cache.The common feature of DSP algorithm is that most processing time is spent on executing a few instructions contained in relatively small loops. Therefore, most DSP processors have special hardware for zero consumption cycle control. Zero consumption cycle refers to the cycle in which the processor can execute a group of instructions without spending time testing the value of the cycle counter, PFSK162 3BSE015088R1and the hardware completes the cycle jump and decay of the cycle counter. Some DSPs also implement high-speed single instruction loops through the super cache of one instruction.
在线问
