i've same problem with comparing values.ex:
i have input from ADC0809 8 bit binary output,came to port1 8051 then i check the range if the range from FF to FA then send 'A' through serial port to computer baud rate 9600, if the range from F9 - F5 send 'B', etc until the range complete checking and the last character send is 'Z' if the value didn't match any of this range it will go back to main menu.
thank you, if you are willing to help me.