Motor Stepper Example

[Shermona7]

hey!!! im using a simple bipolar stepper motor with L297 and L298N and want a degree resolution of 1 degree, both in CCW and CW directions. but im clueless about the coding.

[HenrikOlsson]

The resolution depends on the motor and the type of stepping sequence you do.
Most step-motors from have 200 "natural" steps per revolution - or a step angle of 1.8° per step.
The L297 can do either full- or half-step depending on the state of pin 9. So if your motor has a step angle of 1.8° you get either that or 0.9°
If you need better than that you need to change the motor to one with a more steps/rev (motors with 400 steps/rev are available but not very common) or change the driver to one capable of microstepping.

The L297 is pretty easy to drive. You set the CW/CCW pin high or low depending on which direction you want the motor to move and then give it a pulse on CLOCK pin for each step. Want to move one rev, send a total of 400 pulses (if you're halfstepping with a 1.8°/step motor).

/Henrik.

[Shermona7]

ok!!so the stepper i intend to use is
http://www.geeetech.com/wiki/index.p...rd_for_Arduino
so basically to get a resolution if 1 degree i need to use 0.9 is it? and half and full steps isnt an issue?

would you be able to provide me with the required coding? as im VERY new to C language as well!!!! and thanku soo much for ur reply

[HenrikOlsson]

Hi,
First off all, that motor is an unipolar motor with a single common connection for both windings, it can not be driven by a L298.
The documentation for that motor isn't really that great. It looks like there's a gearbox on the motor but I can't figure out if the stated step angle of 5.625° includes the gearbox, if there is one. If 5.625° includes the gearbox then you won't be able to get 1° resolution. Fullstep would give you 5.625°, halfstep 2.8125°.

Finally this is a forum for PBP, most of us don't do C so if you're looking for that you're in the wrong place basically.

[astanapane]

Hi all,

long time no see, because i'm o the business trip and really didnt have a time to meet you.

I have a question.

First of all i havent open a new thread because it is already one here.

Now let me explain you what i would like to do.

I have the following parts in my lab and would like to do some experiments. Simple not very difficult in the begining.

1) Big Easy Driver
2) Stepper Motor with Cable

Then to control the easy driver i have a pic16f88. I hope that is enough or do i need a bigger microcontroller with 4 different ports?

I understand that i need to connect from the controller to the Big Easy Driver 3 pins.

The GND, the STEP, and the DIR.

My question is: The step has to be a PWM signal? The direction pin is only high or low?

It is would be nice if anyone has a similar questions and will discuss several options.

i just want to give to the stepper motor a simple directions and basic step rotation....not microstep. I know that i can do with the Big easy driver, but i would like to start from the very basics.

thanks a lot for any help in advance.

regards,

[aratti]

Hi astanapane, pic16f88 is more then you need to make your motor turn CW and CCW. Just connect two digital outputs plus the ground to your big easy driver and you are done. Have the pin connected to step toggling with a pause in between shorter is the delay faster the motor will run. Pull high direction pin when you want invert the rotation.

That is all.

Cheers

Al.

[astanapane]

Thanks a lot for the reply. i will give it a little bit more time for searching what i need To do.
Actually i would like to see how i can give a single Step at a time by using pwm.
Appreciate your time.