摘要
设计了以超低功耗单片机MSP430F149为主控芯片的手写绘图板控制系统。系统硬件由恒流源、信号检测、运算放大器、A/D采集、240×128液晶显示、按键输入等模块组成。系统将恒定的直流电流通过覆铜板后产生微小的电势差,并将此信号通过测量电路差分放大和比例放大,转换成可被12位A/D采集的信号;采用TLC2543进行A/D转换,快速采集表笔在绘图板某点的电势后通过软件进行数据处理,计算出触笔所在铜板的位置并输出。该系统已成功用在电子白板上。
The handwrtten drawing board system with the ultra-low-power MSP430F149 as its main control chip is designed. The hardware system is made up of the constant current source,signal detection,operational amplifier,A / D sampling,240 × 128 LCD display,key input module and ordinary copper and so on. The tiny electric potential difference can produce when constant DC flowed the copper board,and the signal is amplified by the differential amplifier and proportional amplifier in measuring circuit,the converted signal using TLC2543 conversion can be sampled by 12 bit A / D,the some point electric potential through software processing is sampled by rapid sampling pens,the output position of pens on the copper board is calculated. This system has been successfully used in the electronic whiteboard.
出处
《湖北理工学院学报》
2014年第6期1-4,13,共5页
Journal of Hubei Polytechnic University
