本科毕业论文外文翻译-温度传感器与无线模块.doc

苏州大学本科生毕业设计（论文）附件：外文文献资料与中文翻译稿外文文献资料收集：苏州大学应用技术学院 11电子班（1116405023）陆妍松Temperature sensor and wireless moduleThis paper is designed a DS18B20 temperature data acquisition system, the system mainly consists of the microcontroller circuit and a digital sensor DS18B20 based. Software, we use keil software writing and debugging the program, the hardware side, we passed Proteus circuit simulation software, hardware, and test, the system is simple, low power consumption, through LCD1602 display the measured temperature. Temperature measurement accuracy of the system is relatively high, and stable communication with the microcontroller and PC.DS18B20 temperature sensor is American DALLAS Semiconductors latest smart temperature sensor, an improved, compared with the traditional thermistor temperature measurement devices, which can be read directly measured temperature, and can be based on actual requirements through simple programming 9 to 12 to achieve a digital readout mode.This design is a simple and practical small digital thermometer, the main components used with a sensor 18B20, microcontroller AT89S52 , one of four common cathode LED, resistor capacitor number. 18B20 support bus line interface, measurement temperature range -55 to +125. Within range-10 to+85, accuracy of 0.5. 18B20 poor accuracy of 2. Temperature directly to the scene bus line digital transfer, which greatly improves the systems interference. The site is suitable for temperature measurement in harsh environments, such as: environmental control, equipment or process control, temperature and other consumer electronics products. The digital thermometer design is divided into five parts, the main controller, LED display section, the sensor part, the reset part, clock circuit. That is part of the master controller microcontroller for storing programs and control circuit; LED display section refers to the four common anode digital tube, to display the temperature; sensor part, that the temperature sensor is used to collect temperature, temperature conversion; reset section that reset circuit. The total process measurement is the temperature sensor to the external environment, and converted spread SCM, SCM after treatment to determine the temperature was passed to the digital display. This design can complete temperature measurement range is -55to +128, due to limited capacity, can not achieve the alarm function.DS18B20 works as follows:DS18B20 internal oscillator is a low temperature coefficient of the oscillation frequency of the oscillator with temperature changes very little, providing a stable frequency count pulse counter 1. A high temperature coefficient of the oscillation frequency of the oscillator is very sensitive to temperature oscillator provides a frequency varies with temperature pulse counter 2 count. Which also implies counting door, the door is opened when the count, DS18B20 on the clock pulse after a low temperature coefficient of the oscillator is counted, and then complete the temperature measurement. Counting the door open time is determined by the temperature, coefficient oscillator, before each measurement, the corresponding first base were placed in -55and subtraction counter a temperature register, subtraction counter 1 and the temperature registers are preset in the corresponding to a base value -55. Subtraction counter 1 low temperature coefficient of the crystal pulse signal generated by subtraction count down counter when a preset value reduced to zero value of the temperature register will add a subtraction counter preset 1 will be re-loaded, subtraction counter a re-start of the low temperature coefficient crystal pulse signal is counted, so the cycle until the count down counter 2 to 0:00, stop accumulating temperature register value when the temperature registers is the measured temperature value. As long as the count has not closed the door to repeat the process, until the temperature reaches the measured temperature value register value, which is the principle of DS18B20 temperature. In addition, due to the DS18B20 single wire communication is done sharing his strict concept slots, so the timing is very important to read and write.DS18B20 internal comparator to quantify the way to determine the temperature registers rounding the least significant bit. After two counter stops counting, the comparator will counter a count in the remaining value is converted to temperature values are compared with 0.25, if less than 0.25, the lowest bit temperature register is set to 0; if higher than 0.25, the lowest bit is set to 1; if greater than 0.75, the lowest bit temperature register is set to 0 and then carry. Thus, after comparing the value obtained after the temperature is the temperature of the value of the final register read, and its last representatives 0.5, rounding the maximum quantization error is 1/2LSB, namely 0.25. Temperature register temperature values expressed in nine data format, the highest bit is the sign bit, the rest eight binary complement form, said temperature. At the end of the temperature measurement, which is nine data dump temporary memory of the first two bytes, the sign bit of the first byte occupied, eight temperature data occupy the second byte. DS18B20 using specific temperature measurement techniques to measure temperature. DS18B20 low temperature coefficient of internal oscillator frequency signal to produce a stable; the same high temperature coefficient oscillator will be converted into a frequency signal measured temperature. When counting the door open, DS18B20 count a door opening time is determined by the high temperature coefficient oscillator. There chip slope accumulator can be compensated for nonlinearity frequency. Temperature measurement result is stored in the register. Temperature under normal circumstances should be nine, but the sign bit extension into high eight, so I finally read out to the 16s complement form.In addition, this design also applied to the wireless module nRF24L01. nRF24L01 wireless communications chips in 2.4 GHz 2.52 GHz license-free ISM band, efficient GFSK modulation, anti-jamming capability; the operating frequency can be divided into 125 channels, supports high-speed frequency hopping can unimpeded in the global wireless market. nRF2401 support multi-point communications between a maximum transfer rate of up to 1Mb / s. Meanwhile nRF2401 chip power consumption is very low, the operating voltage of 1.9V 3.6V, with 0 dBm of power, 1Mb / s transfer rate transmitter, the operating current is only 11.3 mA, the operating current is received only 11.7 mA, power-down mode is 900 nA 1,2. nRF24L01 is currently the smallest and least power consumption, low cost external components at least one RF system-on-chip. nRF24L01 general burst mode is often used to transmit and receive data. When transmitting data, first nRF24L01 configured to transmit mode: then the receiving node address TX_ADDR TX_PLD accordance with the timing and valid data is written by the SPI port nRF24L01 buffer zone, TX_PLD must be written in a continuous low CSN, while writing at the time of launch TX_ADDR the once, then CE is set high for at least 10s, transmit data delayed after 130s; if auto-answer is turned on, then enter the data immediately after the launch nRF24L01 reception mode, receives the response signal (automatic response receiving address should receive TX_ADDR consistent node address). If you receive a reply, then that the communication is successful, TX_DS set high, while TX_PLD removed from the TX FIFO; if no reply is received, it is automatically re-transmit the data (automatic retransmission is turned on), if the number of retransmissions (ARC ) limit is reached, MAX_RT set high, TX FIFO data retention for retransmission again; MAX_RT or TX_DS set high, so low IRQ interrupt is generated to notify MCU. The last successful launch, if CE is low then enter idle mode nRF24L01 1; if sending data stack and CE is high, the first launch into the next; if no data is sent in the stack, and CE is high, then enter idle mode 2. And to transmit the address and data into the FIFO stack area from nRF24L01 chip microcontroller. nRF24L01 when transmitting data, the data is automatically transmitted to add the prefix, address and CRC checksum, then high-speed launch. If you turn the chip auto-answer feature, After nRF24L01 chip data transmission into receive mode immediately, in order to receive the response signal. If you receive a reply, then the communication is successful; if no reply is received, it is automatically re-launch, if the number of retransmissions reaches the upper limit set by the high-profile position MAX_RT register, indicating loss of communication.nRF24L01 when receiving data, you must first be configured to receive, after a delay of 130 s enters the receiving state. When nRF24L01 received data, if it detects a valid address and CRC, when the data is automatically header and CRC check code is removed, and the valid data packet stored in the receive stack. If auto-answer is turned on, the receiver at the same time return into the launch state response signal. After receiving process is completed, nRF24L01 notice microcontroller reads data.nRF24L01 RF protocol can be written to the corresponding configuration word through the SPI port of the chip configuration registers to reflect. Configuration word burst mode total 30 B, is mainly used to set the operating mode, the transmission data width, address width, address, channel, transmission frequency, transmission power, CRC, work status, auto-answer is enabled, the number of automatic retransmission, etc. . Once configured, the process nRF24L01 work, just change its corresponding bit configuration register REXN content, you can send and receive mode to switch between modes.Hardware debugging is relatively simple, first check the inductance of the welding is correct, then used multimeter test or power test. Software debugging can write your program and display hardware correctness test, then were the main program, subroutines read temperature, temperature conversion command subroutine to calculate the temperature data refresh subroutine subprograms and reality programming and debugging, etc. Because DS18B20 and microcontroller serial data transfer, therefore, DS18B20 read / must strictly ensure the read / write timing when writing program; otherwise it will not read the measurement results. For nRF24L01 debugging, you need to collect and transfer the program receive written procedures. This procedure uses the microcontroller written in assembler or C language programming and debugging Keil C51 compiler. Software debugging to normal radio transmitter and receiver and display temperature and temperature changes when the temperature change is displayed, it basically complete. Performance tests are available and have been making machine finished temperature thermometer to measure simultaneously compare.第 9 页中文翻译稿翻译：苏州大学应用技术学院 11电子班（1116405023）陆妍松温度传感器与无线模块本论文是基于DS18B20设计了一种温度数据采集系统，系统主要由单片机电路和一个DS18B20 数字传感器构成。软件方面，我们采用keil软件对程序进行编写以及调试，硬件方面，我们通过Proteus软件对硬件电路进行仿真以及测试，该系统结构简单，功耗较低，通过LCD1602显示所测温度。系统的测温精度比较高，并且能稳定的与单片机和PC 机通讯。DS18B20温度传感器是美国DALLAS半导体公司最新推出的一种改进型智能温度传感器，与传统的热敏电阻等测温元件相比，它能直接读出被测温度，并且可根据实际要求通过简单的编程实现912位的数字值读数方式。本设计是一款简单实用的小型数字温度计，所采用的主要元件有传感器18B20，单片机AT89S52，四位共阴极数码管一个，电容电阻若干。18B20支持“一线总线”接口，测量温度范围-55+125。在-10+85范围内,精度为0.5。18B20的精度较差为2.。现场温度直接以“一线总线”的数字方式传输，大大提高了系统的抗干扰性。适合于恶劣环境的现场温度测量，如：环境控制、设备或过程控制、测温类消费电子产品等。 本次数字温度计的设计共分为五部分，主控制器，LED显示部分，传感器部分，复位部分，时钟电路。主控制器即单片机部分，用于存储程序和控制电路；LED显示部分是指四位共阳极数码管，用来显示温度；传感器部分，即温度传感器，用来采集温度，进行温度转换；复位部分，即复位电路。测量的总过程是，传感器采集到外部环境的温度，并进行转换后传到单片机，经过单片机处理判断后将温度传递到数码管显示。本设计能完成的温度测量范围是-55+128，由于能力有限，不能实现报警功能。DS18B20的工作原理如下：DS18B20内部的低温度系数振荡器是一个振荡频率随温度变化很小的振荡器，为计数器1提供一频率稳定的计数脉冲。高温度系数振荡器是一个振荡频率对温度很敏感的振荡器，为计数器2提供一个频率随温度变化的计数脉冲。其中还隐含着计数门，当计数门打开时，DS18B20就对低温度系数振荡器产生的时钟脉冲后进行计数，进而完成温度测量。计数门的开启时间由高温,度系数振荡器来决定，每次测量前，首先将-55 所对应的基数分别置入减法计数器1和温度寄存器中，减法计数器1和温度寄存器被预置在 -55 所对应的一个基数值。减法计数器1对低温度系数晶振产生的脉冲信号进行减法计数，当减法计数器1的预置值减到0时温度寄存器的值将加1，减法计数器1的预置将重新被装入，减法计数器1重新开始对低温度系数晶振产生的脉冲信号进行计数，如此循环直到减法计数器2计数到0时，停止温度寄存器值的累加，此时温度寄存器中的数值即为所测温度。只要计数门仍未关闭就重复上述过程，直至温度寄存器值达到被测温度值，这就是DS18B20的测温原理。另外，由于DS18B20单线通信功能是分时完成的，他有严格的时隙概念，因此读写时序很重要。 DS18B20内部的比较器以四舍五入的量化方式确定温度寄存器的最低有效位。在计数器2停止计数后，比较器将计数器1中的计数剩余值转换为温度值后与0.25进行比较，若低于0.25，温度寄存器的最低位就置0；若高于0.25，最低位就置1；若高于0.75时，温度寄存器的最低位就进位然后置0。这样，经过比较后所得的温度寄存器的值就是最终读取的温度值了，其最后位代表0.5，四舍五入最大量化误差为1/2LSB，即0.25。温度寄存器中的温度值以9位数据格式表示，最高位为符号位，其余8位以二进制补码形式表示温度值。测温结束时，这9位数据转存到暂存存储器的前两个字节中，符号位占用第一字节，8位温度数据占据第二字节。 DS18B20测量温度时使用特有的温度测量技术。DS18B20内部的低温度系数振荡器能产生稳定的频率信号；同样的，高温度系数振荡器则将被测温度转换成频率信号。当计数门打开时，DS18B20进行计数，计数门开通时间由高温度系数振荡器决定。芯片内部还有斜率累加器，可对频率的非线性度加以补偿。测量结果存入温度寄存器中。一般情况下的温度值应该为9位，但因符号位扩展成高8位，所以最后以16位补码形式读出。此外，本设计还运用到了无线模块nRF24L01。nRF24L01无线通讯芯片工作在2.4 GHz2.52 GHz免许可证ISM频段，高效GFSK调制，抗干扰能力强；工作频率可分为125个信道，支持高速跳频，能够在全球无线市场畅通无阻。nRF2401支持多点间通讯，最高传输速率达1 Mb/s。同时nRF2401芯片能耗非常低，其工作电压为1.9 V3.6 V，以0 dBm的功率、1