you can use the information mentioned in previous post as the pic side program to increase or decrease the speed of a motor as an example. now I want to use ULN2003APG driver to drive a motor.

using ULN2003APG :

pin1 ---> MCU output
pin16 ---> Motor
pin8 ---> Motor GND and MCU GND

and connect vcc to the motor.we use mcu signal to connect gnd to the motor to run with separate vcc but common gnd.