MCS21-ASM7

7281读写C51源程序（键盘与显示），及其相关资料，偶强两天调出来的 与大家共享(7281 to read and write source code C51 (keyboard and display), and related information, even strong two days out of tune with the U.S. share)

说明：  使用555时基电路产生频率为20kHz-50kHz的方波Ⅰ作为信号源；利用此方波Ⅰ，可在四个通道输出4种波形；每通道输出方波Ⅱ、三角波、正弦波Ⅰ、正弦波Ⅱ中的一种波形，每通道输出的负载电阻均为600欧姆。限用NE555、NE5532（或LM358）、电容和电阻若干。(-Waveform generator with schematic + circuit + program)

水箱水位自动控制系统,通过超声波对水位高度的检测，把数据传入到单片机中处理，得出当前水位，并根据当前水位的高低程度调控直流电机和步进电机转动实现水位的增加或减少，从而实现水位的自动控制。(the system of water auto control )

51单片机简单小程序，用keil软件编写，实现数码管的循环移动(51 single simple small program, keil software development, mobile digital tube to achieve the cycle)

液晶显示器与单片机接口电路程序，实现液晶显示对于信号源发生信号的控制和显示(LCD and microcontroller interface circuit procedures, LCD occurred signal source for the control signal and display)

51单片机使用短信Modem发送短消息的例子。(51 MCU send text messages using SMS Modem example.)

stm32f103c8t6上面实现uart3的Irda功能接受红外字符，控制TIM4上面4个通道的pwm输出占空比(stm32f103c8t6 functions to achieve the above uart3 acceptance of Irda Infrared character, control TIM4 above 4 channel pwm output duty)

here is a document describing KEy pad decoding techniques and C++ source code as well. it is show 74ls138 role in decoding.. hope it will be helpful. THANKS

这是一款模拟modbus从机的程序，可以方便用户调试modbus程序，本程序完全免费。(This is a simulation of the modbus from machines, can facilitate users to debug the modbus program, this program is completely free. )

ISIS实现仿真MSP430单片机开发，有MSP430SRVPAK++7.5补丁和测试程序仿真图(ISIS achieve simulation MSP430 development, and testing procedures have MSP430SRVPAK++7.5 patch simulation diagram)