51_ustart

编写一段程序 统计从1000年到1999年之间闰年的个数 最后输出到屏幕上来(writing a program to sum up the numbers of leapyear between 1000 and 1999.Finally,showing the result on the screen.)

读写器与射频卡通信的设计采用RC522射频读写芯片与射频卡进行通信，符合ISO14443规范协议；硬件系统设计中主要有AVR单片机主控模块、电源模块、存储模块、外部时钟模块、LCD模块；软件系统设计采用C语言，遵循模块化和结构化编程模式，设计了射频卡操作程序、软关机与自动关机程序、LCD显示、串行Flash存储器、外部时钟等外部设备驱动程序。所设计的手持式读写器具备对MF1 S50、S70射频卡的读写、实时状态显示、系统在线升级以及关机等功能。(This handset can process the data offline or online, reading and writing from 10 cm far. This handset is low-power, miniature, modular design and so on. This article includes: the communication design between RF card and Reader, hardware system design and software systems design. The communication design between RF card and Reader used to RC522 RF chip control RF cards, in line with ISO14443 standard protocol Hardware system design mainly include AVR microcontroller control modules, power modules, memory modules, external clock modules, LCD modules Software system designed with C programming language, and follow the modular structure of the programming model, and has the RF card operation procedures, soft shutdown and automatic shutdown procedures, LCD display, serial Flash memory, an external clock, and other external device driver Procedures. The handset readers has the MF1 S50, S70 RF card reader function, real-time status display function, the system online update function and so)

带参数存储的整点报时音乐电脑时钟，算是一个比较适合初学者一个小系统。有一定的参考价值。(With parameters stored in the computer clock chime music, be a more suitable for beginners a small system. Have a certain reference value.)

简单的总结si4432的程序资料，非常地实用，简单。(Simple summary si4432 program information is very practical and simple.)

4维简单胞映射程序: 对动力系统做全局分析(four-dimensional simple cell mapping procedures : dynamic systems analysis of the overall situation so)

该程序是CRC校验程序，可以查看文件的校验和，这对文件本身进行校验，也可用在其它程序中检难数据正确与否(CRC procedures can view the document and check that the document itself calibration, but also can be used in other programs Frederick hard data are correct or not)

可以用指令控制选择信道，设置发射功率，发送数据包（长度可选），接收数据包（接收时延可设），CC2430复位,内部温度传感器读取，定时器时长控制。底层函数基本做好，如果要加入新功能，可自行更改。(You can select the channel with the command control, set the transmit power, transmit data packet (lengths), receive data packets (receiver delay can be set), CC2430 reset, the internal temperature sensor reading, the timer duration control. Basic underlying function well, if you want to add new features to make changes.)

改程序适应于电力系统短路电流计算，生成节点导纳矩阵和阻抗矩阵。(Change program suitable for power system short-circuit current calculation, to generate the node admittance matrix and the impedance matrix.)

时钟的应用源代码，可以让初次设计有关定时操作的人员借鉴。 (Clock application source code, allowing designers about the timing of the initial operation of reference.)

一个数字梯形，选择k条路线，每条路线从第一层的某个数开始，每次进入下一层到达左下或者右下的数字，直到最后一层为止。每条路线不能经过相同的路径，但是可以经过相同的数字节点。 输出一个整数，表示能得到的最大的k条路径经过的数字之和(A digital ladder, the K route, each route the first layer of a number, each time to enter the next layer to reach the left or right next to the number, until the final layer. Each route can not pass through the same path, but can pass through the same number of nodes. Output an integer representing the sum of the number of the largest K paths that can be obtained)