On Oct 2, 2006, at 3:16 PM, Martin Peach wrote:

You have to set and clear the four digital outs that go to the motor.

i have the stepper turning by the way of a potentiometer, now is the
pd part where im stuck.

You have to explicitly set and unset each of the four control lines
in a specific sequence.

ok, but if one wants to do this by the way of, say an [hslider], if
possible. How can i get to set/unset 4 messages..uhmm? what would be
the right way to send those patterns to the arduino?

The speed you do it at determines how fast the motor turns. Each
new step is a different pattern.

clear,

The sequence can be found by trial and error. When it's wrong the
motor just jitters. It's not dangerous.

yes, i ve seen that, it doesnt even go as hot as a servo does.

tx again martin /a

On Oct 2, 2006, at 4:55 PM, martin.peach@sympatico.ca
martin.peach@sympatico.ca wrote:

there are four messages that you sequence. With a slider it could
increment or decrement a counter that goes to a select that sends
one of four messages to the arduino. That will work if you move the
slider very slowly to avoid missed values.

i have tried with few metros banging the 4 pins of the arduino
8,9,10,11that "control" the stepper. Its been just random moves from
the stepper, i've read page 99 onwards of the document you suggested
but i just dont seem to know how to create the correct patterns in
pd, the stepper jumps in very small number of jumps then backwards
then onwards... this is sending a pulse with a [metro 100]..

On Oct 2, 2006, at 4:58 PM, Kyle Klipowicz wrote:

You could probably just set the slider to control a metro that bangs the proper message sequence. This would effectively adjust the motor speed.

took me a while to find the bytemask and debytemask objects/patches..
that should be included with the pduino release since the arduino- test.pd patch needs them... (linux 0.3.9 extended test 2 here)..
after digging the list archives i finally found them (http:// lists.puredata.info/pipermail/pd-list/2006-06/039287.html), i thought
they will stop the jittering produced by the different bang
secuences.. nogo... the jumps are to few to be able to understand the
right secuence.

On Oct 2, 2006, at 5:11 PM, Christian Klippel wrote:

my idea would be the following: if it cant do already, change the arduino firmware to accept a byte
that gets send to a arduino port. usually, you need 4 bits for a stepper,
depending on the type. so you can mask away the unused 4 bits, and set the port- lines at once directly. this will give you a much smoother operation of the
stepper as well.

how to know if the pduino firmware, as you said, already do this? as
said above i've banging each pin in all kinds of combinations, the
stepper moves but i dont seem to find a clear pattern that help me
decipher the rest.

any other idea for a patch to get a hold on a stepper from pd using
the pduino? i thought this was easy or was already done from pd..

tx all for the help, /a

hi again,

on a quick note, the sequence for using unipolar 4 coils steppers is:

A B C D coils A - D 1 0 0 0 step1 0 1 0 0 step2 0 0 1 0 step3 0 0 0 1 step4

this is the full step sequence. you can do half-steps as well, practically doubling the number of steps per revolution:

A B C D coils A - D 1 0 0 0 step1a 1 1 0 0 step1b 0 1 0 0 step2a 0 1 1 0 step2b 0 0 1 0 step3a 0 0 1 1 step3b 0 0 0 1 step4a 1 0 0 1 step4b

to make it turn continously, repeat the sequence. to change direction, step from 4 to 1 ....

if you want to use bipolar stepper motors, you need an extra h-bridge driver, so that the polarity of the coil driving voltage can be changed.

greets,

chris