ABSTRACT
Microcontroller technology has spreaded to our lives, work,
scientific research, each domain has become a relatively mature
technology, this paper introduces a kind of based on MCU control of
the digital temperature sensor, thermometer belongs to a
multi-functional thermometer, you can set upper and lower temperature
alarm, when the temperature is not in the set range, can call the
police.
The system is designed to STC89C51 microcontroller as its core
component, use DS18B20 integrated temperature gather temperature
measure the real-time sampling, led LCD display with a higher and a
lower limit on the value of real-time alert temperature, In order to
adapt to changes in the scene, We set up the upper and lower buttons
to adjust the temperature threshold. If the temperature is over the
threshold value, the system will start the buzzer alarm, and turn on
the fan for the engine to cool, make it work in a temperature range
suitable.
The system hardware and software systems to achieve a real-time
monitoring of the water temperature, real-time control, real-time
display and limit alarm-functions. Just right to simulate the engine
in complex situations conditioning system works. STC89C51 18B20 as a
temperature sensor and combined to achieve the temperature detection
system, Since 18B20 has the temperature range of -55 ℃to 125 ℃, in line
with the engine tank normal operating temperatur.The 18B20 has
measurement accuracy of 0.5 ℃, for some small temperature changes can
also be measured. Since the higher and the lower limit guard values a
measuring in the range of normal temperatures in the 18B20. If
software design is good, buzzer and a small fan installed, you can
achieve beyond the warning value alarm functions the system is simple,
Since 18B20 uses water proof design, external lasting isolation,
anti-interference ability, which are suitable for on-site temperature
measurement sin harsh environments, there is a wide range of
applications. At the same time the system is simple, it is universal.
