Digital Thermometer Using 8051 Microcontroller #project#engineering #ece

CODE EXPLANATION- This program is for displaying the temperature on 16*2 lcd display using 8051 microcontroller,lm35 sensor ,ADC0804. For 16*2 LCD interfacing with 8051 microcontroller , we have to define pins on which 16*2 lcd is connected to 8051 microcontroller. RS pin of 16*2 lcd is connected to P2.5 , RW pin of 16*2 lcd is connected to P2.6 and E pin of 16*2 lcd is connected to P2.5. Data pins are connected to port 2 of 8051 microcontroller. Similarly, for ADC0804 interfacing with 8051 microcontroller, we have to define pins on which ADC0804 is connected to 8051 microcontroller. RD pin of ADC0804 is connected to P3.0, WR pin of ADC0804 is connected to P3.1 and INTR pin of ADC0804 is connected to P3.2. Data pins are connected to port 1 of 8051 microcontroller. Next we have to define some functions which are used in the program. Delay function is used to create specified time delay, cmdwrt function is used to send commands to 16*2 lcd display, datawrt function is used to send data to 16*2 lcd display and convert_display function is used to convert the ADC data into temperature and to display it on 16*2 lcd display. After that we are converting the analog voltage produced by LM35 sensor to digital data and then it is converted to temperature and displayed on 16*2 lcd display. For ADC0804 to start the conversion we have to send a low to high pulse on WR pin of ADC0804, then we have to wait for end of conversion. INTR becomes low at the end of conversion. Once INTR becomes low, RD is made low to copy the digital data to port 0 of 8051 microcontroller. After a specified time delay, next cycle starts. This process is repeated forever. We are converting digital data into temperature and displaying it on 16*2 lcd display. After that initializing some predefined function, we are sending commands to 16*2 lcd display. The command is copied to port 0 of 8051 microcontroller. RS is made low for command write. RW is made low for write operation. High to low pulse is applied on enable(E) pin to start command write operation. In this part of the code, we are sending data to 16*2 lcd display. The data is copied to port 0 of 8051 microcontroller. RS is made high for command write . RW is made low for write operation. High to low pulse is applied on enable(E) pin to start data write operation.Similarly we have initialized the rest of the predefined functions