Hello guys, i got an old dvd player and soon decided to make a cnc writing machine. But the thing is, it uses 2 wire motor which I think a dc motor rather than a stepper motor seen now a days. So i want to know how it controls the laser mechanism or that one axis movement with it. I havr attached a photo of it. 
Hi there!
My guess is that the two wires indicate a standard DC motor that uses gear ratio(s) to decrease the speed of rotation. In order to get position control, There may be some sort of encoder that sends data to that little pcb in your picture, which allows to motor to move and stops the motor once the encoder hits the desired position. It is also possible that there is an H-Bridge to control direction of rotation.
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