I can see that you will get output like the following only;
TEMP:0#C
Is it??
Because from the main function you are only calling the following functions related to lcd
lcd_write_data(‘T’);
lcd_write_data(‘E’);
lcd_write_data(‘M’);
lcd_write_data(‘P’);
lcd_write_data(‘:’);
lcd_write_data(48); // Display the temperature
lcd_write_data(0xDF);
lcd_write_data(‘C’);
You are not accessing the temperature data which you’ve stored in the register using i2c communication.