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[on:]

Here is a brief summary of the code.
It can spin a full size DSLR on it's shaft without bearings at 30RPM! 
Ramping up and slowing down to prevent bouncing.
It can measure torque to detect an abnormal load or error.
It works without blocking or waiting or interrupts.
Enhanced performance using 12v without warming up the motor.
And much more!
Sounds like an advert, but it's all for Free.
Hardware is $4.

Variables:
bcw 1 is clockwise 0 is ccw
deg100 9000 is 90 deg
rpm100 1000 is 10 rpm, 100 is sec hand
rph100 hour 100 is like minute hand on clock
percslow 10 is 10% slow at end of move
steppos 90.0*STEPERDEG is 90 deg
steps same
xinrev 0,2,3,4,8x in 360 deg
revo # revolutions
const float STEPERDEG=float(64)*64/360;

These are ordered just like in the code:
void unramp (boolean bcw, long deg100, int rpm100, int percslow)
void unramp1 faster
void moveto (int steppos)
void movetodir (boolean bcw, int steppos)

void midspeedcool_12v (boolean bcw, long steps)
void ramp (boolean bcw, int rpm100)
void revRestart (boolean bcw, long revo, int rpm100, int xinrev)
void rev (boolean bcw, long revo)

void degrpmslowCool4 (boolean bcw, long deg100, int rph100)
void degrpmslowCool4_nowait
int calloften()
void degrpm_nowait (boolean bcw, long deg100, int rpm100)
int calloften_micro (boolean bcw)

void degrpmslowCool (boolean bcw, long deg100, int rph100)
void degrpmslowHot
void degrpmslow2

void degrpmEZ (boolean bcw, long deg100, int rpm100)
void degrpm
void degrpm8
void move (boolean bcw)

1 line description for each function above:
unramp stops bounce at end of move
unramp1 faster
absolute position in degrees shortest direction
absolute choose direction

12v only 1/2 speed
speed up over 90 deg
restarts x in 360 rev
obsolete?

most efficient mAh
slow no wait
fast no wait
look at d in loop

cool 4 step
hot 4 step
mid 4 step

8 step 5 lines simple fast ramp, measure torque
8 step 5 lines +err 2.00deg move delay(10)
microstep speed limit 17RPM
relative move 1 step

ccwss() measures torque and halts program if spike to prevent damage
just hook motor winding to analog pin 0

[Reply #1 on:]

So what is your question?

[Reply #2 on:]

Does anyone want this?
Will you test it more?
How about a single function to detect extra torque and slow down keeping speed to a maximum without stalling?
If I was purely offering it for others I should put it in a different category?

[Reply #3 on:]

Does anyone want this?
Will you test it more?
How about a single function to detect extra torque and slow down keeping speed to a maximum without stalling?
If I was purely offering it for others I should put it in a different category?

You have provided no more than a series of vague statements. Nothing there to test. 

[Reply #4 on:]

Well of course.  I'm working on some new functions and testing myself.  I wasn't sure if anyone was interested.  I've posted most of the code before, but here are a few enhancements.  I wanted to organize it (above) so it's easier to understand without looking inside the functions themselves.  There is no need to unless you're curious like me.  There are only 1 or 2 global variables you might need, and no additional functions to call to setup.  Can you think of any additional functionality I've missed?

[Reply #5 on:]

I'm interested in this, I have 2 of these little motors. Can't believe they have enough power to spin a DSLR. Please make a video of it

[Reply #6 on:]

Please test it and tell me what you think?  You can spin something as heavy!
Just uncomment some of my lines in loop().

[Reply #7 on:]

Did anyone try it yet?

[Reply #8 on:]

Could please post an example sketch using the code # button? I can't figure out the code in the first post.

[Reply #9 on:]

Download the zip file (attached above).  It's not a library yet.  Compile the entire file in IDE.  Uncomment one of the lines in loop() to test it with your motor. 

[Reply #10 on:]

Hi Sbright

I have tried it, works very well so far.
This is good work, there is often questions about this motor in the forum.
And once again i am surprised how smooth this motor runs. And for the torgue, I cant hold it with my fingers.

[Reply #11 on:]

Finally some feedback!  Thank you.  I tried to make it simple.  The 4 nowait functions might confuse someone.  All the functions are calibrated to be accurate according to RPM.  The torque is inverse to the RPM past the startup speed.  At slow speeds the Hot functions have more torque than the cold ones, especially with a 5v supply.  This is at the expense of power consumption.  Please ask if you want to know why I did something in the code.  Did you try the halt when there's too much load subroutine?  You can change it to print the load instead.  Did you see you can turn 1.00 deg 360x and it works!  Or 1.50 deg 240x.  3.00 deg 30x is 90.  Without microstepping.  You get the picture.

You can easily remove the floats to make the code size much smaller.  You only lose movedeg and err functionality.  Only the functions that you use are included in the executable.  Some of my sketches are 1.2K in size.  I think this will work on ATTINY85 with a few changes.

I was thinking of adding sleep between steps when you're going slow.  Anyone want it?

[Reply #12 on:]

I just tried it out, had not seen that you posted the .pde file  It does work very well. I've thought about buying a cheap tripod and add a stepper motor to it to make 360 pano's. Might be possible with this little motor? That's quite a bit of code you have written, hats off to you!

[Reply #13 on:]

http://www.amazon.com/gp/product/B0000AUR21/ref=cm_cr_mts_prod_img
This is much better in the real world with big lenses making a GigaPan, it's sturdy.
I wrote a simple library for it. You just need a screwdriver to modify it.
I removed the internal stops and made a simple one on the outside.
You could design a bearing to use with our tiny motors.
But I just mounted my T2i on the shaft!  Made a wooden base for the motor.
It works fine so long as you have a level table or rock to set it on.
The Bescor goes 7deg/sec max.
Our stepper 30RPM which works out to 180deg/sec or 25x as fast.
Too fast to stop blur with a 200mm lens spinning on it.
That's why I wrote unramp() to stop and start.
With the Bescor I can take a panorama or Gigapan without stopping @300mm.
With the stepper I can capture 360 deg in 2 seconds.
I've been making endless panoramas, they just keep going and going, round and round...
Faster than this, 1/8th the price:
http://gigapan.org/cms/shop/epic-pro

[Reply #14 on:]

Haha, many times I have almost ordered a Gigapan. But the local camera shop over here wants 1000€ for the pro version. Which I need for my Nikon D300/700. Never heard of the Bescor, looks like a nice cheap solution. It's on my wanted list, thanks for the info.