基于AT89C52單片機(jī)的步進(jìn)電機(jī)控制系統(tǒng)設(shè)計(jì)
摘 要: 提出了一個(gè)由AT89C52單片機(jī)控制步進(jìn)電機(jī)的實(shí)例。可以通過(guò)鍵盤(pán)輸入相關(guān)數(shù)據(jù), 并根據(jù)需要, 實(shí)時(shí)對(duì)步進(jìn)電機(jī)工作方式進(jìn)行設(shè)置, 具有實(shí)時(shí)性和交互性的特點(diǎn)。該系統(tǒng)可應(yīng)用于步進(jìn)電機(jī)控制的大多數(shù)場(chǎng)合。實(shí)踐表明, 系統(tǒng)性能優(yōu)于傳統(tǒng)的步進(jìn)電機(jī)控制器。
關(guān)鍵詞: 單片機(jī); 步進(jìn)電動(dòng)機(jī); 直流固態(tài)繼電器; 實(shí)時(shí)控制
ABSTRACT: A stepp ing motor control system based on AT89C52 chip microcomputer was described.The data can be inputwith keyboard, and stepp ingmotorwas controlled by these data. According to the demand, users can Set the workingmodel of stepp ingmotor in real2time. This system can be widely used in stepp ing motor controlling. The p ractice showed that the performance of this system outdid the tradi-tional stepp ing motor controller.
雖然PIC都是8位的單片機(jī)，但都采用RISC（Reduced Instruction Set Computing）核心結(jié)構(gòu)，這有別于過(guò)去一般的CISC(Complex Instruction Set Computing)結(jié)構(gòu)。所謂RISC結(jié)構(gòu)就是采用哈佛雙總線(xiàn)結(jié)構(gòu)，將地址總線(xiàn)與數(shù)據(jù)總線(xiàn)分開(kāi)，因此在同一個(gè)指令執(zhí)行過(guò)程中，數(shù)據(jù)與地址可以同時(shí)傳送，避免了總線(xiàn)處理上的瓶頸。
匯編器在微處理器的驗(yàn)證和應(yīng)用中舉足輕重，如何設(shè)計(jì)通用的匯編器一直是研究的熱點(diǎn)之一。本文提出了一種開(kāi)放式的匯編器系統(tǒng)設(shè)計(jì)思想，在匯編語(yǔ)言與機(jī)器語(yǔ)言間插入中間代碼CMDL（code mapping description language）語(yǔ)言，打破匯編語(yǔ)言與機(jī)器語(yǔ)言的直接映射關(guān)系，由此建立起一套描述匯編語(yǔ)言與機(jī)器語(yǔ)言的開(kāi)放式映射體系。基于此開(kāi)放式映射體系開(kāi)發(fā)了一套匯編器系統(tǒng)，具有較高層次上的通用性和可移植性?！娟P(guān)鍵詞】指令集，CMDL，匯編器，開(kāi)放式
Design of Retargetable Assembler System Liu Ling Feng Wen Nan Wang Ying Chun Jiang An Ping Ji Li Jiu IME of Peking University, 100871【摘要】An assembler plays a very important role in the field of microprocessor verifications and applications, thus how to build a retargetable assembler system has been a hotspot in this field for long time. This paper presents a new method about the retargetable assembler system design.It provides a kind of language CMDL, code mapping description language. During the process of assembling, assembler languages are firstly translated to CMDL, and then mapped to the machine codes. In an other word, CMDL is inserted between assembler languages and machine codes during the translation procedure. As a medium code, CMDL has a lot of features, such as high extraction, strong descript capabilities. It can describe almost all attributes of assembler languages. By breaking the direct mapping relationship between assembler languages and machine codes, the complexities of machine codes are hided to the users, therefore, the new retargetable assembler system has higher retargetable level by converting the mapping from assembler languages and machine codes to assembler languages and CMDL, and implementationof it becomes easier. Based on the new mapping system structure, a retargetable assemblersystem is developed. It proved the whole system has good retargetability and implantability.【關(guān)鍵詞】instruction Set, symbol table, assembler, lexical analysis, retargetability
The PCA9544A provides 4 interrupt inputs, one for each channeland one open drain interrupt output. When an interrupt is generated byany device, it will be detected by the PCA9544A and the interruptoutput will be driven LOW. The channel need not be active fordetection of the interrupt. A bit is also Set in the control byte.Bits 4 – 7 of the control byte correspond to channels 0 – 3 of thePCA9544A, respectively. Therefore, if an interrupt is generated byany device connected to channel 2, the state of the interrupt inputs isloaded into the control register when a read is accomplished.Likewise, an interrupt on any device connected to channel 0 wouldcause bit 4 of the control register to be Set on the read. The mastercan then address the PCA9544A and read the contents of thecontrol byte to determine which channel contains the devicegenerating the interrupt. The master can then reconfigure thePCA9544A to select this channel, and locate the device generatingthe interrupt and clear it. The interrupt clears when the deviceoriginating the interrupt clears.
The C500 microcontroller family usually provides only one on-chip synchronous serialchannel (SSC). If a second SSC is required, an emulation of the missing interface mayhelp to avoid an external hardware solution with additional electronic components.The solution presented in this paper and in the attached source files emulates the mostimportant SSC functions by using optimized SW routines with a performance up to 25KBaud in Slave Mode with half duplex transmission and an overhead less than 60% atSAB C513 with 12 MHz. Due to the implementation in C this performance is not the limitof the chip. A pure implementation in assembler will result in a strong reduction of theCPU load and therefore increase the maximum speed of the interface. In addition,microcontrollers like the SAB C505 will speed up the interface by a factor of two becauseof an optimized architecture compared with the SAB C513.Moreover, this solution lays stress on using as few on-chip hardware resources aspossible. A more excessive consumption of those resources will result in a highermaximum speed of the emulated interface.Due to the restricted performance of an 8 bit microcontroller a pin compatible solution isprovided only; the internal register based programming interface is replaced by a Set ofsubroutine calls.The attached source files also contain a test shell, which demonstrates how to exchangeinformation between an on-chip HW-SSC and the emulated SW-SSC via 5 external wiresin different operation modes. It is based on the SAB C513 (Siemens 8 bit microcontroller).A table with load measurements is presented to give an indication for the fraction of CPUperformance required by software for emulating the SSC.
This application note shows how to write an Inter Integrated Circuit bus driver (I²C) for the Philips P90CL301micro-controller.It is not only an example of writing a driver, but it also includes a Set of application interface software routines toquickly implement a complete I²C multi-master system application.For specific applications the user will have to make minimal changes in the driver program. Using the drivermeans linking modules to your application software and including a header-file into the application sourceprograms. A small example program of how to use the driver is listed.The driver supports i.a. polled or interrupt driven message handling, slave message transfers and multi-mastersystem applications. Furthermore, it is made suitable for use in conjunction with real time operating systems, likepSOS+.
This application note demonstrates how to write an Inter Integrated Circuit bus driver (I2C) for the XA-S3 16-bitMicrocontroller from Philips Semiconductors.Not only the driver software is given. This note also contains a Set of (example) interface routines and a smalldemo application program. All together it offers the user a quick start in writing a complete I2C system applicationwith the PXAS3x.The driver routines support interrupt driven single master transfers. Furthermore, the routines are suitable foruse in conjunction with real time operating systems.
