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By Pascal1966
#194253
Hi,
I just bought this stepper motor below to be controled by a arduino UNO:
Elegoo 5 sets 28BYJ-48 ULN2003 5V Stepper Motor + ULN2003 Driver Board for Arduino.
Questions: tutorials all show the pins connected to 8,9,10,11: does that matter? can I use other pins like 5,6,7,8?
What is the stepsPerRevolution?
Step angle: 5.625 x 1/64
It seems to me that it is either: 360/5.625 = 64 (motor itself)
or: 64 x 64 = 4096 (motor + gearing)
However, when i run the motor step by step on one revolution, I count only 2048 steps.
What's wrong?
By jremington
#194258
Yes, you can use different pins.
What's wrong?
Are we supposed to guess? Post your code, using code tags.
By Pascal1966
#194263
Thanks. I indeed tried other pins and it works the same.
I confirm that the number of steps per revolution seems to be 20148, which does not seem coherent with the specs... I have asked Elegoo directly, we'll see what they say.
By Pascal1966
#194769
Thanks all for the responses.
So it turns out to be a 32 steps motor (the step motor itself), but with the gearing at 64:1 , the output shaft has 2048 'slow' steps.
The initial confusion comes from the manufacturer's specs; 5.625 degree per step: that's wrong: 360/32 = 11.25 degree.
so the internal stepper has 32 steps and 11.25 degree per step, which translates to 32x64 = 2048 steps and 360/2048 = 0.17578 degree at the output shaft.
The overall package makes for a quite "high def" little stepper assembly!