[PD] how to pd2stepper motor?

[Martin Peach]

Hans-Christoph Steiner wrote:
>
> On Oct 6, 2006, at 12:14 AM, Martin Peach wrote:
...
>> As far as steppers go it would be nice to have arduino commands for 
>> steppers. It looks like the existing pduino firmware code can only 
>> change one pin at a time, it would be nice to have a parallel digital 
>> pin command with a mask like set_digital_outs(int output_pattern, int 
>> mask) so the set bits in mask would be changed, at the same time, 
>> according to output_pattern and the zero bits would be unaffected.
>
> Couldn't the stepper commands be written as Pd objects or is the 
> serial port too slow?  Do you know the maximum speed you can send the 
> stepper control pulses?
>
I just tried it yesterday with a bipolar (4-wire) stepper from an old 5 
1/4" floppy drive and a dual h-bridge. It worked well if I sent the bit 
patterns in sequence. The metro was running at around 15ms at the 
smoothest rotation. Faster than about 10 it started missing steps. The 
patch is just a counter that bangs a sequence of four numbers into arduino.

> Also, are there standardized patterns for steppers?
>
Here are some:
http://www.appliedmotionproducts.com/support/wiring.php
I don't know how standard they are. It usually doesn't take long to 
figure them out from scratch, you can't damage the motor.
The coils can be found with an ohmmeter, the sequence by trial and error.
Martin
> .hc
>