本文件是一个3*4键盘扫描显示程序, 初学者往往对此类问题感到头疼, 本人特上传一个供大家参考....

单片机用T1中断在IO口P1.0输出乐曲(在P1.0口与VCC间接一喇叭即可听到) 1.由于输出的是方波，比较难听:-)你也可以将波形细分用DA输出正弦波 2.由于T1频繁中断，任何其他中断发生都会是乐曲打顿，只适合试验 3.优化音符编码：一个字节中包含节拍、音符、升降调，可区分数据和命令 -Single-chip microcomputer used in the IO port T1 interrupt output music P1.0 (P1.0 port with VCC in the indirect one can hear the speaker) 1. As the output is a square wave, more bluntly :-) You can also fine-waveform DA output sine wave with sub-2. Due to the frequent interruption of T1, any other interruption occurs Dayton will be playing music, is only suitable for test 3. optimized coding notes: A byte contains rhythms, notes, take-off and landing tune can distinguish between data and command

简易谐波分析仪 -Simple Harmonic Analyzer

便携式压力传感器，带usb口和ic存储卡的-portable pressure sensors, with USB port and memory card ic

是一款开发板的外围电路试验程序(附有原理图) -Is a development board of the external circuit testing procedures (with schematic diagram)

Proteus与AVR应用实例,非常好的例子，大家可以下载-Proteus with the AVR application examples, very good example, you can download

ATMEL公司的AT89S系列51单片机ISP软件-ATMEL the AT89S Series 51 software microcontroller ISP

单片机详细的试验 基于c的详细的软件操作和硬件实现方式-Singlechip c Based on a detailed test of the detailed software and hardware implementations

网上搜集的IDE控制的c51程序，可以研究一下。-online collection of IDE control of the decoder procedure could look into.

JUPITER演示程序，lcd显示，实例。-JUPITER demo program, lcd display, examples.

LCD7920汉字液晶操作程序，已经在产品使用中，-LCD7920 LCD characters operational procedures, already in use in the product,