i just saw program of line follower robot at your website link is here to post
http://circuitdigest.com/microcontroller-projects/line-follower-robot-u…
as clear from the circuit 4 bit output is going from MC to the motor driver and the table that is used to write hex from binary gives hex codes as below
0x0A to move both motors forward
0x08 to turn robot right
0x02 to turn it left
0x00 to stop
but in program you wrote
0x06 to move it forward
0x82 to move it left(how it could be possible to provide 8 bit output using 4 data lines ? as clear from schematic 4 data lines are going to motor driver
0x14 to move right
0x00 stop
if this program is correct then please explain me how you genrated this hex code ? how it is possible to use 8 bit in 4 bit mode?