Hi,Steve Taylor,

Here have two question:
a)if I use PWM wave to drive the DC-motor,
the motor torgue maybe be reduce,it will
influence the power of drive.
I will experience the test:
1.__|~~~~|___________|~~~~|__________

2.__|~~~~|__|~~~~|__|~~~~|__|~~~~|__

I think 2 will have bigger torque than 1,
b)if DC-Motor is brushless,it can use
back-EMF technology,if the DC- Motor have brush,it's control is different,
if use the EMF chip,it will increase
my design cost,because it is toys application,I don't want to increase
many chips,i will use to two driver transistors,it can do the positive and
reverse rotation.(but it will need two port pins)

-John cason