Nowadays, science and technology is more and more developed, we can reach and need to carry on temperature survey and temperature control to different occasions through various effective ways. This paper will introduce a kind of temperature measure annunciator that made up of single-chip microcomputer, sensor, etc. . Control-chip adopts the AT89S51 series single-chip microcomputer, the sensor adopts the one-line digital temperature sensor DS18B20, the keyboard adopts the scanning type uncoded keyboard, displayer adopts two dynamic display mode LED, uses buzzer as the sound-warning device. Function that circuit design in this paper is to measure two nodal temperature value, and set the most high and low-temperature limit for any chosen sensor ; Can also compare temperature between two nodes, get the difference in temperature; When some nodal temperature exceeds most high or low-temperature and two nodes’ difference in temperature prescribed in advance, buzzer sounds as warning, and reserves each sensor’s temperature. The temperature measure range of DS18B20 is -55 °c～+125°c, and the precision is 0.5°c. In this paper, we use the range of 0°c～99°c C°
, and the display precision of 1°c.
Keywords: single-chip microcomputort; DS18B20; AT24C02; temperature; difference in temperature.
