ieee754的标准,原英文版的!Twenty years ago anarchy threatened floating-point arithmetic. Over a dozen commercially significant arithmetics boasted diverse wordsizes, precisions, rounding procedures and over/underflow behaviors, and more were in the works. “Portable” software intended to reconcile that numerical diversity had become unbearably costly to develop. Thirteen years ago, when IEEE 754 became official, major microprocessor manufacturers had already adopted it despite the challenge it posed to implementors. With unprecedented altruism, hardware designers had risen to its challenge in the belief that they would ease and encourage a vast burgeoning of numerical software. They did succeed to a considerable extent. Anyway, rounding anomalies that preoccupied all of us in the 1970s afflict only CRAY X-MPs — J90s now.
上传时间: 2017-07-28
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microprocessors are getting smaller, cheaper and faster. Every day, it is easier to embed more functionality into a smaller space. Embedded processors have become pervasive, and as time goes on, more and more functions that were once implemented with analog circuitry or with electromechanical assemblies are being realized with microcontrollers, ADCs and DACs. Many of these assemblies that are being supplanted by the microprocessor are controlling dynamic processes, which is a good thing, because the microprocessor coupled with the right software is often the superior device.
上传时间: 2016-07-20
上传用户:kunger
The GL823K integrates a high speed 8051 microprocessor and a high efficiency hardware engine for the best data transfer performance between USB and flash card interfaces. Its pin assignment design fits to card sockets to provide easier PCB layout. Inside the chip, it integrates 5V to 3.3V regulator, 3.3V to 1.8V regulator and power MOSFETs and it enables the function of on-chip clock source (OCCS) which means no external 12MHz XTAL is needed and that effectively reduces the total BOM cost.
上传时间: 2022-04-27
上传用户:qdxqdxqdxqdx
摘要:介绍了以FreeModbus协议找在嵌入式抢占实时操作系统μC/OS-l的STM32平台上,成功实现了Modbus协议的移植。通过详细分析FreeModbus协议花并编写STM32F103VET6微处理器的底层驱动,成功实现了工业Modbus协议RTU和ASCll两种模式的通信功能。测试结果表明,在实际工业生产控制和仪表开发中,应用Freemodbus协议,完全符合工业数据采集、实时控制和数据处理等厂级重复性和精确度要求,在一定程度上降低了工业仪表开发的周期及成本。关键词:实时操作系统,uC/OS-ll,FreeModbus,Modbus协议,STM32Abstract:This paper introduces FreeModbus stack transplanted to the STM32 platform which has been embedded in the preemptive real-time operating system uC/OS-ll,in order that the transplantation of the Modbus protocol is successfuly im-plemented.The FreeModbus stack is analyzed in detail and STM32F103VET6 microprocessor underlying driver is writed,so that the two Modbus industrial communication function RTU and ASCll are successfully realized.Keywords:time operating system,uC/OS-ll,.FreeModbus,Modbus协议,STM32
标签: freemodbus 通信协议
上传时间: 2022-06-25
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MPC5748This reference manual is intended for system software and hardware developers andapplications programmers who want to develop products with this device. It assumes thatthe reader understands operating systems, microprocessor system design, and basicprinciples of software and hardware.
标签: MPC5748G
上传时间: 2022-07-25
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