激光治疗仪中的触摸屏接口设计

各种触摸屏的应用简化了人机交互过程。介绍四线电阻式触摸屏的工作原理及在激光治疗仪中的应用。阐述ADS7846同微控制器PIC16F876的数据传递过程。     

基于Linux液晶显示触摸屏控制的新设计与实现

在分析电阻触摸屏和ADC的工作原理的基础上,采用微处理器LM3S4749自带模块ADC和GPIO代替触摸屏专用控制器ADS7846.设计出LM3S3749与液晶显示触摸屏接口电路的硬件连接,并给出必要的序流程图和函数代码.提出触摸屏触点坐标的获得方法与液晶屏显示同步的算法,以提高设计触摸屏与液晶的效率,满足控制精度.     

电阻式触摸屏多点校准及触摸压力研究

针对电阻式触摸屏在小点状目标应用环境中存在触点判断不准确、灵敏度不高的问题,提出两种改进措施;其一在现有三点校准算法基础之上,增加校准点数提高转换精度;通过贪心算法对随机校准点集进行优化约简,并利用最小二乘法求得校准系数;其二为提高触摸坐标的准确性和触摸方式的鲁棒性,加入触摸压力检测和阈值判定来去除无效点击;测试结果表明,基于贪心算法的多点校准可提高坐标校准系数的精度,而触摸压力判定的加入则有效提高了轻触时的坐标精度。     

基于USB的在线签名数据采集系统

笔迹信息的采集是在线签名识别算法的基础.本系统是由触摸屏、触摸屏控制器ADS7846、单片机AT89C52构成的基于USB的在线签名数据采集系统,实现了对签名笔迹的坐标、速度及压力信息采集.     

基于uClinux的触摸屏驱动程序设计

本文简述了触摸屏硬件控制电路及其工作原理,详细分析了触摸屏控制芯片(ADS7846)和SPI总线的工作原理,并对LPC2210与ADS7846之间的通信过程进行了具体介绍。重点论述了uClinux下驱动程序的结构,并结合触摸屏硬件控制平台给出了触摸屏驱动程序设计的详细开发过程。     

基于MSP430的大面积电阻式触摸屏信号检测电路的设计

对大面积电阻式触摸屏信号检测电路进行硬件设计和软件编程,实现大面积电阻式触摸屏作为输入装置,通过电阻屏控制芯片ADS7846,MSP430单片机为核心控制器,实现数据的接收、处理和发送功能,通过上位机MATLab工具GUI中一个友好界面显示其功能.硬件设计包括大面积电阻触摸屏、触摸屏控制器和单片机之间的连接、计算机接口设计、单片机与上位机通信设计;软件设计主要包括电阻屏线性校正、单片机对电阻屏控制器的编程设计、单片机与上位机通信编程设计和上位机软件编程设计.通过测试,系统具有较好的应用效果.     

触摸屏在嵌入式系统中的应用

触摸屏逐渐取代键盘成为嵌入式系统常选用的人机交互工具。本文以电阻式触摸屏和触摸屏控制器ADS7846为例介绍了触摸屏及其控制器的原理,然后在分析SPI的基本原理与逻辑结构基础上,对Motorola 32位微控制器MMC2107的SPI模块编程结构进行了较深入的剖析,给出了基本的编程要点。最后以一个应用实例说明如何用触摸屏及其控制器构成嵌入式系统的输入系统。     

基于C8051F SPI接口液晶触摸屏的控制设计

本文简述了液晶触摸屏控制的工作原理,ADS7846触摸屏控制器与SPI接口与SED1335和单片机的接口电路,介绍了液晶触摸屏触点坐标的获取和实现及在液晶屏上换算的算法,并给出了采用单片机C8051F021控制LCD触摸屏的应用与SPI通讯的软件流程。     

PXA255处理器上触摸屏控制的实现

在当前的嵌入式设备中,触摸屏作为人机接口得到了广泛的应用.本文讨论了在基于PXA255处理器的开发平台上使用ADS7846和UCB1400控制芯片完成触摸屏模块的硬件设计,以及ADS7846在Linux操作系统中的软件驱动程序.     

基于RS-232的在线签名数据采集系统

在线签名识别技术在银行金融系统及个人身份识别等领域正引起广泛关注。笔迹信息的采集是在线签名识别算法的基础,目前国内基于签名的数据采集系统的研究刚刚起步。本系统是由触摸屏、触摸屏控制器ADS7846、液晶屏、液晶屏控制器SED1335、单片机AT89S52构成的基于RS232的在线签名数据采集系统,实现了对签名笔迹的坐标、速度及压力信息的采集。     

Text entry on handheld computers by older users

Small pocket computers offer great potential in workplaces where mobility is needed to collect data or access reference information while carrying out tasks such as maintenance or customer support. This paper reports on three studies examining the hypothesis that data entry by older workers is easier when the pocket computer has a physical keyboard, albeit a small one, rather than a touch-screen keyboard. Using a counter-balanced, within-subjects design the accuracy and speed with which adults over 55 years of age could make or modify short text entries was measured for both kinds of pocket computer. The keyboard computer was the Hewlett Packard 360LX (HP), but the touch-screen computers varied across studies (experiment 1: Apple Newton and PalmPilot; experiment 2: Philips Nino; experiment 3: Casio E10). All studies showed significant decrements in accuracy and speed when entering text via the touch-screen. Across studies, most participants preferred using the HP's small physical keyboard. Even after additional practice with the touch screen (experiments 2 and 3) many entries still contained errors. Experiment 3 showed that younger people were faster but not more accurate than older people at using the touch-screen keyboard. It is concluded that satisfactory text entry on palm-size computers awaits improvements to the touch-screen keyboard or alternative input methods such as handwriting or voice. Interface developments that assist older people typically benefit younger users too.     

Text entry on handheld computers by older users

Small pocket computers offer great potential in workplaces where mobility is needed to collect data or access reference information while carrying out tasks such as maintenance or customer support. This paper reports on three studies examining the hypothesis that data entry by older workers is easier when the pocket computer has a physical keyboard, albeit a small one, rather than a touchscreen keyboard. Using a counter-balanced, within-subjects design the accuracy and speed with which adults over 55 years of age could make or modify short text entries was measured for both kinds of pocket computer. The keyboard computer was the Hewlett Packard 360LX (HP), but the touch-screen computers varied across studies (experiment 1: Apple Newton? and PalmPilot?; experiment 2: Philips Nino?; experiment 3: Casio E10?). All studies showed significant decrements in accuracy and speed when entering text via the touch-screen. Across studies, most participants preferred using the HP's small physical keyboard. Even after additional practice with the touch screen (experiments 2 and 3) many entries still contained errors. Experiment 3 showed that younger people were faster but not more accurate than older people at using the touch-screen keyboard. It is concluded that satisfactory text entry on palm-size computers awaits improvements to the touch-screen keyboard or alternative input methods such as handwriting or voice. Interface developments that assist older people typically benefit younger users too.     

基于ARM微处理器的液晶触摸屏的接口设计

作为人机交互的重要手段,液晶触摸屏使用越来越多,基于微控制器与触摸屏的接口技术在工业控制、智能家电等领域得到应用广泛,开发徼控制器与液晶触摸屏的接口技术是智能电子产品设计的重要工作;介绍了一款液晶触摸屏系统的总体设计方案、电路接口和编程方法;该系统由TFT液晶屏模块,触摸屏和ARM微处理器控制板组成;TFT液晶模块内置SSD1289控制器,尺寸3.2英寸、分辨率240×320像素;触摸屏由触摸传感部件和触摸屏控制器ADS7843组成;控制板采用ARM7徽处理器LPC2148为控制核心;测试和工程实践结果表明,所设计的软、硬件达到了各项要求,并且具有操作方便、稳定性好,性价比高等技术特点,有较好的推广应用价值.     

基于ANDROID4．X触摸功能的智能电视电脑一体机方案

随着智能数字云电视和个人PC进入每个家庭,触摸屏输入功能的设备也取代了传统的键盘鼠标,而支持ANDROID4．X触摸功能的智能电视电脑一体机也会作为新一代典型的物联网应用而进入千家万户。为此,文中阐述了能支持ANDROID4．X触摸功能的智能电视电脑一体机的实现方案,详细介绍了触摸屏电视电脑一体机的实现方法、系统硬件实现和软件系统选用等。     

混凝土搅拌控制系统的设计与应用

系统使用nTouch触摸屏和欧姆龙CP1H型号PLC,其称重部分使用称重仪表。nTouch触摸屏及其嵌入软件MCGS既可以在触摸屏上使用,也可以很方便地连接到工控机,达到了适用于不同场合、不同需求的目的。PLC的部分梯形图采用ST语言编程。达到了加密、方便使用的特殊要求。称重仪表通过串行通讯,达到了对其远程数据传输的目的。     

Qt/Embedded 触摸屏的智能家居无线传输系统设计①

设计了一个基于Qt/Embedded触摸屏的智能家居控制平台,并通过zigbee组网的方式,实现家居的智能化控制。首先,智能家居的界面用Qt/Embedded设计,然后,界面被移植到以ARM9为微处理器的控制平台上,并实现界面的触摸屏功能;最后,通过串口驱动将设计的具有触摸屏功能的界面与zigbee组网的协议连接起来,实现对智能家居控制的无线传输。     

嵌入式Linux触摸屏驱动开发

根据触摸屏坐标检测原理和压力检测方法,以AD7887芯片为例讲述了触摸屏控制电路的控制原理和方法;以Intel StrongARM嵌入式系统为平台,介绍Linux下触摸屏驱动程序的开发方法。系统通过AD转换芯片采样触摸屏数据,做模数转换后通过CPU的串口送给系统.触摸屏驱动程序包括AD7887和SA1110相关控制寄存器的硬件初始化,驱动程序的流程和构架,引入内核定时器的重要意义,以及坐标数据的处理。     

Qt／Embedded触摸屏的智能家居无线传输系统设计

设计了一个基于Qt/Embedded触摸屏的智能家居控制平台,并通过zigbee组网的方式,实现家居的智能化控制。首先,智能家居的界面用Qt／Embedded设计,然后,界面被移植到以ARM9为微处理器的控制平台上,并实现界面的触摸屏功能;最后,通过串口驱动将设计的具有触摸屏功能的界面与zigbee组网的协议连接起来,实现对智能家居控制的无线传输。     

Effect of key size and activation area on the performance of a regional error correction method in a touch-screen QWERTY keyboard

Manual text entry, which is one of the main features of mobile communications devices, decreases the competitive advantages of full touch-screen interfaces over physical interfaces. Especially for small full QWERTY keyboards, text entry becomes more problematic because of the small size of the virtual keys, absence of tactile feedback, and occlusion of virtual keys by fingers. One solution to this problem is the regional error correction, which is a predictive text entry method that activates the key corresponding to the actual activation point and also other keys within an activation area. This study investigates how the size of keys and of the activation area affect the accuracy of the regional error correction and compares the regional error correction method with the conventional finger touch method, for a touch-screen QWERTY keyboard. The regional error correction reduced both the time and the number of touches required to complete text entry when keys were small, but no difference was observed when keys were large. Users’ subjective assessments of ease of use and preference indicated greater satisfaction with the regional error correction method than without it, regardless of key size.Relevance to industry: The result of this study can be used to speed and simplify text entry in mobile devices with full-QWERTY virtual keyboards.