Arduino stepper - arduino

I am building a system with the Arduino Uno, a power shield (REf to model) and a bipolar stepper motor.
I cannot initiate the motor using the stepper library from Arduino. I instantiate my stepper with
Stepper myStepper(motorSteps, motorPin1,motorPin2m motorPin3,motorPin4);
And keep on with the example code provided with the Arduino.
When I launch the code on the Arduino, the motor emits some sounds, but it does not turn.
How can determine the right motor pins to use? On the power shield, which mode is to be used, PWM or PLL?

As you suggest, the adafruit motor shield should fit the arduino stepper library, as it uses a L293D to drive the motor. It can drive 2 stepper with an current of 0.6A (good for most of little stepper you can find in printers, floppy/CD/DVD reader...).
Be careful, they seem to use their own library for this shield, you can find it here :
http://www.ladyada.net/make/mshield/download.html
And to know how to connect your stepper, look here :
http://www.ladyada.net/make/mshield/use.html
Sorry to answer your comment this way, but I don't have enough reputation to comment... so please, +1 my answer if you think it's a good answer :)

It's normal that the arduino sketch doesn't work. It drives the motor like this:
PIN1 : coil 1, forward current
PIN2 : coil 1, backward current
PIN3 : coil 2, forward current
PIN4 : coil 2, backward current
Your shield drives the stepper this way:
PIN1 : current forward/backward
PIN2 : current intensity with PWM
PIN3 : current intensity with PWM
PIN4 : current forward/backward
Not a good idea to drive a stepper motor, as you don't even need PWM to drive a stepper. It's to drive a DC motor. You may write your own sketch to drive a stepper with that shield, but you should find a shield that fit the arduino to drive a stepper. Look for something like "UL2003 stepper module", it costs few dollars.
Edit: I've got one of those modules and it works like a charm. Be careful about the power you need. Maybe you need something like a L298N module. I've got few of them too and they work fine.

If the motor emits some sound, this is good news. At least you have contact with it. Since it is just a sound but no movement, there might be three things laying underneath of this behavior;
Wrong pin connections of the motor
Insufficient current feeding from the motor driver.
Step counts determined by the code using PWM might be
too less or too high as per the motor can handle.
I can offer this URL link to determine motor pin-outs;
How Can I Determine My Stepper Motor Wiring Without the Stepper Motor Pinout

In stepper motor how many wires you have? 4 or 6.
Your connection is faulty. That's why it makes such sound.
Test with multimeter. you find two wires give high resistance. other two give half from that. Connect the first two with motor driver out1 and second two with out2.
You didn't mention which motor driver you are using. Try with L298 motor driver shield.

I think the problem you are having is related to the kind of shield you are attempting to use. The power shield that you linked is designed for DC motors and you are attempting to use a stepper motor (see this website for an explanation of the difference).
I would recommend trying another shield (like the Sparkfun EasyDriver) that supports the use of a stepper motor.

The problem seems to be wrong connected motor pins.
Are you sure, you connect true windings to motor?
Measure the motor pins with ohmmeter. There should be two windings which have pins A1-A2 and B1-B2. Between these pins you should see some resistance value.
Then be sure you connect to shield with right order.

In mi projects I use a bipolar motor (a nema17), and you can drive it easy with a A4988 pololu (or drv8825, more powerfull, and more expensive).
Those drivers has an H bridge inside, and allows you to control the motor by a simple:
while(1){
digitalWrite(PIN_STEP, HIGH);
delay(1000);
digitalWrite(PIN_STEP, LOW);
delay(1000);
//1RPM = 100 microsecond delay for a 1.8 degree angle motor (200 steps per
turn)
}

Related

doit.am 4-way motor & 16-way servo shield board not working with adafruit libraries

Got a servo + motor driver arduino shield with a robotic arm chassis from amazon. Found this link on the web :
https://github.com/SmartArduino/SZDOITWiKi/wiki/2-4ch-DC-motor-%26amp%3B-16ch-servo-shield---motor-and-servo-shield
Not enough details to help me control servos/ motors for my own project.
Tried the libraries given in the answer to this question:
doit 2-way motor & 16-way servo shield board
The libraries have been included, but i can't figure out how to use it properly. Ran the sample code as given in the adafruit website :
https://learn.adafruit.com/16-channel-pwm-servo-driver/using-the-adafruit-library
The 0th channel didn't move the servo as expected so I don't know what to try next.
Alright guys, here's the complete reply, with some precautions for future users.
The shield can be used via the library available at https://learn.adafruit.com/16-channel-pwm-servo-driver/using-the-adafruit-library.
(Shoutout to #djsfantasi ).
NOTE : One of the main things to ensure is that the 5v power supply for the servos must be separate from that of the arduino, as it messes up the servos somehow.
The motors can be powered via the given slots on the shield. All you have to do is supply the DIR and PWM values to the 1st 8 available arduino pins (after pin 0 and 1, ie, 2-9). It is pretty easy to figure out which pin controls which channel.
NOTE: Since the motor pins are available via male headers stacked very close together, i would suggest using female headers/jumper wires before connecting them to your motors. I burned my 1st shield's motor driver due to the +ve and -ve ending up shorted together.
Thanks for the replies everyone and best of luck to you guys reading this.

Sim 900 GPRS shield pinout

I'm currently working on a project involving a GPRS Shield based on Sim 900 Chip
I was wondering if anyone would know which ones are the VIN Pin and the RING pin ?
It doesn't say on the board itself and all other searches have lead me to a dead end.
Also if you have a detailed pin layout it would be much appreciated.
Thank you
The GPRS shield is the one in the link below
http://imgur.com/a/1a2gx
Ring Pin
If you have a Multimeter with continuity testing, check where the RI pin (#4) on the Sim 900 chip is broken out to. Here is an overview of the pins:
If it isn't (some shields don't have them broken out) you could solder a wire to the RI pin with an LED and resistor to Ground, something like this:
[RI Pin]--------[wire]--------[LED]--------[Resistor (330Ohms?)]--------[Ground]
The ring indicator is HIGH by default and LOW when there is an incoming call. So, when there is no call the LED is on and off when there is an incoming call.
VIN
When the position of the switch (middle left in the image below) is set to "extern" (right), you have to supply power to the barrel connector. When you set the switch to the left position, the module takes power from the 5V pin of the arduino OR (dont attach both!) an external power supply you attach to that pin.
Hope it helps :)
PS: These SIM modules can have current peaks up to 2 Amps. I recommend you to use an external power source that can provide minimum 2A at 5V.
Edit:
This might be helpful:
http://wiki.seeed.cc/GPRS_Shield_v1.0/. I think its the same module as yours. Have a look at the "GPRS Shield v1.4 Schematic" at the bottom of the page.
Edit 2:
Comparing the board from the link and yours, i'm very certain that the ring pin is the one marked in red in the image above. Checking with a multimeter doesnt hurt though. You can add the same circuit i described above to that pin to add an LED indicator.

Arduino analogRead function pin 0 not working

I would like to know if someone met the same problem on Arduino board. Know if there is a solution ?
My Arduino board has only 1 month. The pin 0 worked well before. I don't know if it's possible to "burn" a pin. (ex : use a too high voltage ? )
Output A0 connected to 5V Output A1 connected to V
On the screenshots you provided it shows the value on the pin, so technically speaking your analogRead has no problems. Check the link and connections. But regarding your question - yes, you can burn pin and even board with high voltage, so don't forget resistance when it's needed.
Also good practice to use arduino macro for analog pins like analogRead(A0); which is perfectly fine for arduino
Your screenshots show that the values read from A0 are changing (190 first, 300 second). That suggests that the problem lies in the electrical connection. Try to resolder the A0 connector pin, and possibly appropriate pin of the microcontroller. Check if the path leading from the connector to microcontroller pin is not cut somewhere.

How to control a motor with two inputs using arduino

I am using an arduino uno and I am trying to control a motor with two inputs which I found in a small car I used to have as a child.
I connected the first pin of the motor to the arduino ground and the second one to the VCC and the motor started turning.
However, when I write the following code the motor doesn't work.
void setup() {
pinMode(8,OUTPUT);
digitalWrite(8,HIGH);
}
void loop() {
}
(I have connected the first pin of the motor to the ground and the second one to pin 8 of arduino).
Does anybody know why that happens?
You can only get a certain amount of current from an Arduino output pin. In general, you can light an LED with a direct connection to an output pin, but motors require more current. A detailed discussion is here.
To control a device such as a motor which needs more current than the output pin can provide directly, you can use an external transistor. You can buy circuits that implement this idea, such as this Motor Shield for Arduino.
This is not how Arduino is supposed to work with power consuming stuff (like mhopeng said, you may use LED in such a scheme, but not something more consuming): a motor should be between GND and 5V and if you want to control it, you have to use a transistor connected to an output pin.
I had a similar question once, it may be of help, too. Also, it may be a good idea to ask further questions at arduino.SE.

Turn on light (bulb) with Arduino UNO and PIR Sensor

im trying to turn on the light (bulb) with my arduino UNO and one module with 4 relays. I can do it with one LED but with an bulb i can't. I have connected the wires like in the photo:
http://i.stack.imgur.com/GUuAS.jpg
I need a 1k ohm resistor or the module include it??
Here the bulb that I have:
http://i57.tinypic.com/10dbp90.jpg
Thanks!!!
In your wiring picture it appears that the only source of power is what the Arduino is getting from the USB cable. The purpose of a relay is typically to control the flow of a higher voltage source (such as multiple small batteries in series, a larger battery, or a wall outlet) using a lower voltage control signal (e.g. one of your Arduino's GPIO pins). The maximum current from VCC to ground that can be draw without damaging your Arduino is 200 mA (source). Power = voltage * current (p = i * v) and VCC is 5V. This means the total amount of power your Arduino can supply is 1 watt. This is likely significantly less than the amount of power required to turn on your light bulb.
The purpose of the resistor in the LED circuit is to limit the current going through the LED. This is more commonly done when the LED is connected directly to a GPIO pin in order to prevent more current from being drawn from a pin than the amount that will damage that pin. From the same source as the current limit from VCC, the limit for a GPIO pin is only 40 mA. I would recommend seeing if you can power your light bulb with a battery. You could then use this same size battery as the power source for your relay board.

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