Luminary Micro provides an analog-to-digital converter (ADC) module on some members of theStellaris MICROcontrolLER family. The hardware resolution of the ADC is 10 bits; however, due to noiseand other accuracy-diminishing factors, the true accuracy is less than 10 bits. This application noteprovides a software-based oversampling technique, resulting in an improved Effective Number OfBits (ENOB) in the conversion result. This document describes methods of oversampling an inputsignal, and the impact on precision and overall system performance.
标签： Oversampling Techniques ADC fo
上传时间： 2013-12-17
上传用户：zhyiroy
基于PIC单片机的脉冲电源:设计了一种金属凝固过程用脉冲电源。该电源采用PIC16F877作为主控芯片，实现对窄脉冲电流幅值的检测，以及时电流脉冲幅值根据模糊PID算法进行闲环控制。使用结果表明：该电源的输出脉冲波形良好，电流幅值稳定，满足合金材料凝固过程的工艺要求且运行稳定可靠。关键词：脉冲电源；PIC16F877单片机；模糊PID；闲环控制 Abstract：A kind of pulse power supply was designed which uses in the metal solidification process ．．I11is power supply used PIC16F877 to take the master control chip reali on to the narrow pulse electric current peak-to-peak value examination，carried on the closed-loop control to the electric current pulse peak-to-peak value basis fuzzy PID algorithm．The use result indicated ，this power supply output se profile is good，and the electric current peak-to-p~k value is stable，It satisfies the alloy material solidification process the technological requirement and movement stable reliable，Key words：p se po wer supply；PIC16F877single-chip MICROcontrolLER；f r PID；closed-loop control
上传时间： 2013-10-27
上传用户：xcy122677
基于单片机的除尘控制器的设计:介绍通用控制仪的硬件组成和软件设计,阐述了系统的性能指标和功能特点。该产品功能完善,可靠性高,具有很好的应用前景。关键词: 除尘器;通用控制仪;单片机;系统设计 Abstract: The hardware structure and the software design are introduced in this paper, and the performance index and the features of the system are expounded. It has comp rehensive functions, high reliability and good app lication.Key words: dust catcher; universal controller; MICROcontrolLER; system design
上传时间： 2013-11-16
上传用户：ming52900
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.
标签： synchronous Emulating serial
上传时间： 2014-01-31
上传用户：z1191176801
The μPSD32xx family, from ST, consists of Flash programmable system devices with a 8032 MICROcontrolLERCore. Of these, the μPSD3234A and μPSD3254A are notable for having a complete implementationof the USB hardware directly on the chip, complying with the Universal Serial Bus Specification, Revision1.1.This application note describes a demonstration program that has been written for the DK3200 hardwaredemonstration kit (incorporating a μPSD3234A device). It gives the user an idea of how simple it is to workwith the device, using the HID class as a ready-made device driver for the USB connection.IN-APPLICATION-PROGRAMMING (IAP) AND IN-SYSTEM-PROGRAMMING (ISP)Since the μPSD contains two independent Flash memory arrays, the Micro Controller Unit (MCU) can executecode from one memory while erasing and programming the other. Product firmware updates in thefield can be reliably performed over any communication channel (such as CAN, Ethernet, UART, J1850)using this unique architecture. For In-Application-Programming (IAP), all code is updated through theMCU. The main advantage for the user is that the firmware can be updated remotely. The target applicationruns and takes care on its own program code and data memory.IAP is not the only method to program the firmware in μPSD devices. They can also be programmed usingIn-System-Programming (ISP). A IEEE1149.1-compliant JTAG interface is included on the μPSD. Withthis, the entire device can be rapidly programmed while soldered to the circuit board (Main Flash memory,Secondary Boot Flash memory, the PLD, and all configuration areas). This requires no MCU participation.The MCU is completely bypassed. So, the μPSD can be programmed or reprogrammed any time, anywhere, even when completely uncommitted.Both methods take place with the device in its normal hardware environment, soldered to a printed circuitboard. The IAP method cannot be used without previous use of ISP, because IAP utilizes a small amountof resident code to receive the service commands, and to perform the desired operations.
标签： Demonstration 3200 USB for
上传时间： 2014-02-27
上传用户：zhangzhenyu
The μPSD32xx family, from ST, consists of Flash programmable system devices with a 8032 MICROcontrolLER Core. Of these, the μPSD3234A and μPSD3254A are notable for having a complete implementation of the USB hardware directly on the chip, complying with the Universal Serial Bus Specification, Revision 1.1.This application note describes a demonstration program that has been written for the DK3200 hardware demonstration kit (incorporating a μPSD3234A device). It gives the user an idea of how simple it is to work with the device, using the HID class as a ready-made device driver for the USB connection.
上传时间： 2014-04-03
上传用户：lizhizheng88
Internal Interrupts are used to respond to asynchronous requests from a certain part of theMICROcontrolLER that needs to be serviced. Each peripheral in the TriCore as well as theBus Control Unit, the Debug Unit, the Peripheral Control Processor (PCP) and the CPUitself can generate an Interrupt Request.So what is an external Interrupt?An external Interrupt is something alike as the internal Interrupt. The difference is that anexternal Interrupt request is caused by an external event. Normally this would be a pulseon Port0 or Port1, but it can be even a signal from the input buffer of the SSC, indicatingthat a service is requested.The User’s Manual does not explain this aspect in detail so this ApNote will explain themost common form of an external Interrupt request. This ApNote will show that there is aneasy way to react on a pulse on Port0 or Port1 and to create with this impulse an InterruptService Request. Later in the second part of the document, you can find hints on how todebounce impulses to enable the use of a simple switch as the input device.Note: You will find additional information on how to setup the Interrupt System in theApNote “First steps through the TriCore Interrupt System” (AP3222xx)1. It would gobeyond the scope of this document to explain this here, but you will find selfexplanatoryexamples later on.
上传时间： 2013-10-27
上传用户：zhangyigenius
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.
上传时间： 2013-11-02
上传用户：zw380105939
The 87LPC76X MICROcontrolLER combines in a small package thebenefits of a high-performance MICROcontrolLER with on-boardhardware supporting the Inter-Integrated Circuit (I2C) bus interface.The 87LPC76X can be programmed both as an I2C bus master, aslave, or both. An overview of the I2C bus and description of the bussupport hardware in the 87LPC76X MICROcontrolLERs appears inapplication note AN464, Using the 87LPC76X MICROcontrolLER as anI2C Bus Master. That application note includes a programmingexample, demonstrating a bus-master code. Here we show anexample of programming the MICROcontrolLER as an I2C slave.The code listing demonstrates communications routines for the87LPC76X as a slave on the I2C bus. It compliments the program inAN464 which demonstrates the 87LPC76X as an I2C bus master.One may demonstrate two 87LPC76X devices communicating witheach other on the I2C bus, using the AN464 code in one, and theprogram presented here in the other. The examples presented hereand in AN464 allow the 87LPC76X to be either a master or a slave,but not both. Switching between master and slave roles in amultimaster environment is described in application note AN435.The software for a slave on the bus is relatively simple, as theprocessor plays a relatively passive role. It does not initiate bustransfers on its own, but responds to a master initiating thecommunications. This is true whether the slave receives or transmitsdata—transmission takes place only as a response to a busmaster’s request. The slave does not have to worry about arbitrationor about devices which do not acknowledge their address. As theslave is not supposed to take control of the bus, we do not demandit to resolve bus exceptions or “hangups”. If the bus becomesinactive the processor simply withdraws, not interfering with themaster (or masters) on the bus which should (hopefully) try toresolve the situation.
上传时间： 2013-11-19
上传用户：shirleyYim
Presents short and simple I2C software routines that support onlyslave (rather than master or master & slave) operation and an ASMdemonstration program. The slave-only software in this app notecomplements the master mode software presented in AN464, Usingthe 87LPC76X MICROcontrolLER as an I2C bus master.
上传时间： 2013-11-22
上传用户：1039312764
