Hi Sum,

There are 2 easy ways:

You must first measure the smallest pulse width, at which any motion was done.

1.
Simple generate such pulses with longer pauses.
Then the pulse - pause - ratio determine the speed.

2.
Whith powering the motor forward and backward with the same pulse width, the resulting speed was zero.
And with varying the pulse ratio you can get a very little faster moving in forward than in backward direction (or reverse).
This result in a very slow average speed.

3.
On combining these both methods, the speed was the slowest.
E.g.:
10.5ms forward - 10ms backward - 200ms pause - ...
Seems equal to powering a 12V motor with 0.03V.
The only difference: it moves !


Peter