to run a script at start-up on my Raspberry pi 3 board ( with  jessie lite ) :

1- I added one init script under /etc/init.d/ directory. I can start,stop,restart service using script manually. 

    ### BEGIN INIT INFO
    # Provides: LCD
    # Required-Start: $remote_fs $syslog
    # Required-Stop: $remote_fs $syslog
    # Default-Start: 2 3 4 5
    # Default-Stop: 0 1 6
    # Short-Description: Liquid Crystal Display
    # Description: date / time / ip address
    ### END INIT INFO
     
     
    #! /bin/sh
    # /etc/init.d/lcd
     
     
    export HOME
    case "$1" in
        start)
            echo "Starting LCD"
           /root/Ccodes/charlcd &
        ;;
        stop)
            echo "Stopping LCD"
    	killall charlcd
        ;;
        *)
            echo "Usage: /etc/init.d/lcd {start|stop}"
            exit 1
        ;;
    esac
    exit 0

2-i made the script executable:

    "sudo chmod 755 /etc/init.d/lcd"

3-an then Register script to be run at start-up 

    sudo update-rc.d lcd defaults

the script does not start on boot.

any suggestions?  

by the way i can sucsessfully run it at boot using RC.LOCAL
https://www.raspberrypi.org/documentation/linux/usage/rc-local.md