设计了一种基于PIC16C71单片机的数字水温配制阀。该配制阀采用NTC热敏电阻作温度传感器,与固定电阻组成简单分压电路作为水温测量电路,利用PIC16C71单片机内置的8位A/D转换器把热敏电阻上的模拟电压转换为数字量,PIC16C71单片机控制直流电机驱动混水阀调节冷热水的混合比例实现水温调节。给出了控制电路图,对水温测量电路的参数选择和测温精度作了详细讨论。实验和分析表明,选用阻值较大的NTC热敏电阻和分压电阻可较好地解决热敏电阻因功耗较大造成的热击穿问题。 Abstract: A digital valve for controlling water temperature based on PIC16C71 was presented in this paper.A bleeder circuit which consisted of a NTC thermistor as temperature sensor and a fixed resistance was designed as water temperature measuring circuit.The analog voltage on the thermistor was converted into digital signal by a 8-bit A/D converter embedded in PIC16C71. Based on the digital signal, the MCU PIC16C71 drived the valve by a DC motor to adjust the water temperature through adjusting the proportion of hot water and cold water.The circuit diagram of controller was given,the principle,the component parameters and the accuracy of measuring temperatures were also dissertated in detail. It was found by experiment and analysis that thermal breakdown of thermistor caused by high power could be solved by selecting thermistor and fixed resistance with high impedance value.
上传时间: 2013-11-08
上传用户:Yue Zhong
目录: 1. Character Type Functions - 字符类型函数 2. Standard C Input/Output Functions - 标准输入输出函数 3. Standard Library Functions - 标准库和内存分配函数 4. Mathematical Functions - 数学函数 5. String Functions - 字符串函数 6. BCD Conversion Functions - BCD 转换函数 7. Memory Access Functions - 存储器访问函数 8. Delay Functions - 延时函数 9. LCD Functions - LCD函数 10. LCD Functions for displays with 4x40 characters - 4×40 字符型LCD函数 11. LCD Functions for displays connected in 8 bit memory mapped mode -以8 位外部存储 器模式接口的LCD显示函数 12. I2C Bus Functions - I2C 总线函数 13. National Semiconductor LM75 Temperature Sensor Functions - LM75 温度传感器函数 14. Dallas Semiconductor DS1621 Thermometer/Thermostat Functions - DS1621 温度计函 数 15. Philips PCF8563 Real Time Clock Functions - PCF8563 实时时钟函数 16. Philips PCF8583 Real Time Clock Functions - PCF8583 实时时钟函数 17. Dallas Semiconductor DS1302 Real Time Clock Functions - DS1302 实时时钟函数 18. Dallas Semiconductor DS1307 Real Time Clock Functions - DS1307 实时时钟函数 19. 1 Wire Protocol Functions - 单线通讯协议函数 20. Dallas Semiconductor DS1820/DS1822 Temperature Sensors Functions - DS1820/1822 温度传感器函数 21. SPI Functions - SPI 函数 22. Power Management Functions - 电源管理函数 23. Gray Code Conversion Functions - 格雷码转换函数
上传时间: 2013-10-22
上传用户:归海惜雪
描述 P89C660/662/664/668单片机内带6KB/32KB/64KB/64KBFlash存储器,该存储器既可并行编程也可以串行在系统编程(ISP).在实际的成型产品中,可通过ISP升级用户程序在BootROM程序. 在Boot ROM程序中,可通过一个默认的串行下载器(UART)对Flash存储器作ISP编程,而在Flash代码区中并不需要有调用下载器的代码,用户程序可通过调用在Boot ROM中的标准子程对Flash存储器擦写和再编程(即IAP).
上传时间: 2013-10-18
上传用户:ouyang426
Mega16是一款采用先进RISC精简指令,内置A/D的8位单片机,可支持低电压联机 Flash和EEPROM 写入功能;同时还支持 Basic和C 等高级语言编程。用它设计电子时钟不仅成本低,硬件简单,而且很容易实现系统移植。介绍了如何利用AVR系列单片机Mega16及1602字符液晶来设计电子时钟的方法,同时给出了相应的电路原理及部分语言程序。 Abstract: ?Mega16 is a high-performance, low power consumption, the use of advanced RISC concise instructions, built-in A/D 8-bit microcontrollers, the on-line support for low-voltage Flash, EEPROM write function. Except Mega16 also support the Basic, C, and other high-level language programming.The electronic clock which is deisgned by Mega16 is not only low-cost, simple hardware, but easy to achieve system migration.The design method of electrioic clock based on the AVR Mega16 and character LCD1602 is introduced in this paper,and the corresponding circuit electrionic and some language program are given.
上传时间: 2014-12-27
上传用户:zl5712176
1 FEATURES· Single chip LCD controller/driver· 1 or 2-line display of up to 24 characters per line, or2 or 4 lines of up to 12 characters per line· 5 ′ 7 character format plus cursor; 5 ′ 8 for kana(Japanese syllabary) and user defined symbols· On-chip:– generation of LCD supply voltage (external supplyalso possible)– generation of intermediate LCD bias voltages– oscillator requires no external components (externalclock also possible)· Display data RAM: 80 characters· Character generator ROM: 240 characters· Character generator RAM: 16 characters· 4 or 8-bit parallel bus or 2-wire I2C-bus interface· CMOS/TTL compatible· 32 row, 60 column outputs· MUX rates 1 : 32 and 1 : 16· Uses common 11 code instruction set· Logic supply voltage range, VDD - VSS: 2.5 to 6 V· Display supply voltage range, VDD - VLCD: 3.5 to 9 V· Low power consumption· I2C-bus address: 011101 SA0.
上传时间: 2013-11-08
上传用户:laozhanshi111
MCS-51系列单片机芯片结构:2.1 MCS—51系列单片机的结构原理2.1.1 MCS-51单片机逻辑结构 MCS-51单片机的系统结构框图如图2.1所示。 图2.1 MCS-51单片机的系统结构框图由图2.1可以看出,单片机内部主要包含下列几个部件:u 一个8位CPU;u 一个时钟电路;u 4Kbyte程序存储器;u 128byte数据存储器;u 两个16位定时/计数器;u 64Kbyte扩展总线控制电路;u 四个8-bit并行I/O端口;u 一个可编程串行接口;五个中断源,其中包括两个优先级嵌套中断 1. CPU CPU即中央处理器的简称,是单片机的核心部件,它完成各种运算和控制操作,CPU由运算器和控制器两部分电路组成。(1)运算器电路 运算器电路包括ALU(算术逻辑单元)、ACC(累加器)、B寄存器、状态寄存器、暂存器1和暂存器2等部件,运算器的功能是进行算术运算和逻辑运算。 (2)控制器电路 控制器电路包括程序计数器PC、PC加1寄存器、指令寄存器、指令译码器、数据指针DPTR、堆栈指针SP、缓冲器以及定时与控制电路等。控制电路完成指挥控制工作,协调单片机各部分正常工作。
上传时间: 2013-10-27
上传用户:tianyi223
MC9S08QG8英文资料 The MC9S08QG8 is the newest member of the Freescale 8-bit family of highly integratedmicrocontrollers, based on the high-performance yet low power HCS08 core. The MC9S08QG8is an excellent solution for power-sensitive applications with extended battery life and maximum performance down to 1.8VDC.
上传时间: 2014-12-28
上传用户:dxxx
1.The C Programming Language is a powerful, flexible andpotentially portable high-level programming language. 2.The C language may be used successfully to create a programfor an 8-bit MCU, but to produce the most efficient machinecode, the programmer must carefully construct the C Languageprogram.3.The programmer must not only create an efficient high leveldesign, but also pay attention to the detailed implementation.
上传时间: 2013-12-27
上传用户:huanglang
This application note describes how to decode standard DTMF tones using the minimum number of external discrete components and a PIC. The two examples use a PIC which has an 8 bit timer and either a comparator or an ADC, although it can be modified for use on a PIC which has only digital I/O. The Appendices have example code for the 16C662 (with comparator) and 16F877 (using the ADC). As the majority of the Digital Signal Processing is done in software, little is required in the way of external signal conditioning. Software techniques are used to model the individual elements of a DTMF Decoder IC.
上传时间: 2013-11-21
上传用户:zhaoke2005
The PCA9555 is a 24-pin CMOS device that provides 16 bits of General Purpose parallelInput/Output (GPIO) expansion for I2C-bus/SMBus applications and was developed toenhance the NXP Semiconductors family of I2C-bus I/O expanders. The improvementsinclude higher drive capability, 5 V I/O tolerance, lower supply current, individual I/Oconfiguration, and smaller packaging. I/O expanders provide a simple solution whenadditional I/O is needed for ACPI power switches, sensors, push buttons, LEDs, fans, etc.The PCA9555 consists of two 8-bit Configuration (Input or Output selection); Input, Outputand Polarity Inversion (active HIGH or active LOW operation) registers. The systemmaster can enable the I/Os as either inputs or outputs by writing to the I/O configurationbits. The data for each Input or Output is kept in the corresponding Input or Outputregister. The polarity of the read register can be inverted with the Polarity Inversionregister. All registers can be read by the system master. Although pin-to-pin and I2C-busaddress compatible with the PCF8575, software changes are required due to theenhancements, and are discussed in Application Note AN469.
上传时间: 2013-11-13
上传用户:fredguo