Cheap stepper driver, no documentation little help?

Hey everyone,

I had little to no money and decided to buy a cheap stepper driver for a project I am working on. It is the Wrobot L298N Motor Driver Shield V3.0

This is a 4.8-46V, 2A Dual Motor Controller which uses ST L298N dual full-bridge driver. Its performance has been improved greatly. It is a high voltage, high current dual full-bridge driver designed to accept standard TTL logic levels and drive inductive loads such as relays, solenoids, DC and stepping motors. Drive current up to 2A per motor output.

I cant say it has NO documentation it offers the following links http://www.emartee.com/Attachment.php?name=41891.pdf http://emartee.com/Attachment.php?name=41988.pdf

Neither of these which I can understand...

I have a Stepper Motor which I wish to run at 1.5 Amps and am not sure how to use this driver board.

I was hoping some one with a little more experience with the L298N could help me with how they function, hooking it up and driving it from the arduino.

Any push in the right direction would be awesome.

Thanks, Kriogenic.

Well first off google for the data sheet of the L298N, it contains the vital information.

I have a Stepper Motor which I wish to run at 1.5 Amps

Yes but at what voltage? This chip is not a regulating driver and so the only way you can control the current is through the voltage you apply to it. Do you have a unipolar or bipolar motor? Measure the coil resistance and work out the voltage you need for your required current. You will then have to get a power supply at that voltage or build a voltage regulator.

Sorry I was in a rush when writing the first post as I was on the train and running out of coverage range..

I know the process in controlling the voltage and have my power supply sorted out and it is a regulated supply. I meant to write that the stepper motor is designed for 1.5 Amps and I wish to hook it up to this particular motor driver Unfortunately I have no idea where to begin with even hooking up this driver to the arduino as all the description said was Arduino compatible....

I realize it is a cheap driver board and didn't expect much from it overall but I would like to get something out of it.

I need help in the hooking it up to Arduino correctly and I also realize this is not really the forum to be asking such questions but if you head over to THEIR forum you would see that it is utterly hopeless a sign perhaps to how bad their equipment actually is?

I'm sure I could work out how to drive the board if I knew its pinouts correctly like... I figure Power + and Power - on the screw terminals would be the regulated voltage in to drive the stepper. But I have no idea about INA, INB, INC, IND? I also assume PWMA and PWMB is the PWM signal to control the steps?

but like I said I have really no idea as the board also has a jumper ::::

first 2 :: are R_EN 1 and 2 (with a jumper on R_EN1 : ) last 2 :: are PWM_EN 1 and 2 (with a jumper on PWM_EN 1 : )

I have no idea what the first two mean? I figure the last 2 are PWM enable for output one or two?

Again sorry I know this forum has NOTHING to do with this particular situation, I was hoping some one may know some more information and can shed some light on its usage.

Thanks, Kriogenic.

OK I will ask again because this is really important:- Do you have a unipolar or bipolar motor?

Have you downloaded the data sheet on the device as this answers most of your questions.

But I have no idea about INA, INB, INC, IND?

These are inputs that control each side of the two bridges. INA & INB control the first bridge - when they are different the coil placed between two outputs is energised, when they are the same it is not. The logic value on INA (and inverse on INB) determines what direction the current flows. This is only for a bipolar motor, if you have a unipolar motor you can't use this chip / shield to control it.

I also assume PWMA and PWMB is the PWM signal to control the steps?

No you don't control the steps with PWM, in your case you control the steps by outputting a pattern of energisation to the coils. It is likely that these inputs are to the enable line of the chip and are used for controlling the speed of a DC motor, with PWM, you don't have one of these.

See this for a bipolar motor:- http://www.thebox.myzen.co.uk/Workshop/Motors_4.html and this for a unipolar:- http://www.thebox.myzen.co.uk/Workshop/Motors_3.html

Hi, The original manufacturer page is here: http://item.taobao.com/item.htm?id=3219336614&

If you run Google Chrome browser, it can translate quite a bit of the Chinese...

some overall info here; http://arduino-info.wikispaces.com/MotorDrivers

Guess I need to write a real how-to for these, with example code... In my Other Spare Time :D

Unfortunately it can not translate over half the page because they are images with Chinese written in them.

I think I know now how to hook the driver up to the Arduino and run it using the Stepper library. Its 2:38am here and my stepper is to loud to turn on at the moment so I will test it first thing in the morning and see if it all works...

I have pins 5 and 6 as INA and INB. 7 and 8 as INC and IND

I have the driver hooked up to a powersupply and have setup the Stepper example with the correct stepping information for my motor.

So hopefully it will work without a hick I'm still not 100% sure its hooked up right... Only time will tell.

I tried what I said above and the driver board LEDS are showing that I am getting signal from the arduino properly, however I am getting no output at motor1 and motor2.

Anyone know more about this board and its jumper settings?

Thanks, Kriogenic.

however I am getting no output at motor1 and motor2.

How are you detecting this by power measurements or lack of motor movement?
Have you connected the ground on your external supply to the ground on the Arduino?
What have you done with the PWM lines, these should be wired high if you are not using them.

Thanks for all the help.

It is all functioning perfectly now.

Thanks again, Kriogenic.

So for the record, and benefit of future readers, what was the problem and how did you set those jumpers?