> > >of its moods, I am unable to send programs to it, the oopic
appears to
> > >lock up and/or restart and keep looping. Further, if I tell the
> > >stepper to go x number of steps the program loops and stutters
> > >in-between iterations. Why such unwanted behavior?
ALWAYS, ALWAYS, put OOPic.Delay = 500 as the first executable
statement in EVERY program. This will allow the IDE to get the
attention of the OOPic for the first 5 seconds following a reset.
Yes, the 5 second delay in program startup is a PITA.
There is still the possibility that the problems are electrical. I
have never used a driver like the L293D but I have used the object to
drive 4 MOSFETS as a unipolar motor.
What voltage is the motor rated for? What voltage are you using?
Have you accounted for the voltage drop in the driver chip? The
overall voltage drop through the driver is between 2.6V and 3.6V.
Look at Voh and Vol in the datasheet here:
http://www.ti.com/lit/gpn/l293d page 5.
Have you looked at the output pins with a scope? Do you have a common
connection between logic ground at the OOPic and ground at the driver
chip? It may not be clear that the Gnd pin of the schematic is ground
for the L293D and ground for the motor. It also needs to connect to
ground at the OOPic. A very deliberate STAR connection is usually
best so that motor ground current doesn't flow over the logic ground
wire to the OOPic. That Gnd terminal shown in the schematic is the
center point of the star. Run the motor ground lead direct to that
point and run a separate logic ground direct to that point.
I realize your hardware is probably not identical to the schematic but
the idea is to get the grounds to tie together as close to the L293D
pins as possible.
Richard
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