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28byj 48 stepper motor

  1. 28BYJ-48 - 5V Stepper Motor The 28BYJ-48 is a small stepper motor suitable for a large range of applications. Rated voltage : 5VDC Number of Phase 4 Speed Variation Ratio 1/64 Stride Angle 5.625° /64 Frequency 100Hz Idle In-traction Frequency > 600Hz Idle Out-traction Frequency > 1000H
  2. Information about the 28BYJ-48 stepper motor and ULN2003 driver board. The 28BYJ-48 is one of the cheapest stepper motors you can find.Although it is not super accurate or powerful, it is a great motor to use for smaller projects or if you just want to learn about stepper motors
  3. Above findings show that 28BYJ-48 is a tin-can stepper motor (also called can-stack motor or claw-pole motor). The rotor is permanent magnet so it is a permanent magnet (PM) stepper motor. Electrical connections reveal it is a unipolar stepper motor. Current applied through the coil magnetizes the claws
  4. This project is an easy introduction to stepper motors and aims to introduce null-level beginners to stepper motors and their respective drivers. This project used 28byj-48 stepper motor and UNL-2003 stepper motor driver. This project is based on the arduino UNO microprocessor
  5. 28BYJ-48 Stepper motor has a wide use in industrial applications and robotics. It is a 4 phase stepper motor. It is very widely used. 28BYJ-48 is usually sold with the driver circuit next to it. It is necessary to use drive modules to start stepper motors. Because the motors draw a lot of current. This is more than the current that.
  6. The 28BYJ-48 motor is a permanent magnet (PM) type stepper and thus share similar characteristics with other PM steppers. A PM stepper motor has a rotating part (rotor) made out of permanent magnet and a stationary part (stator) of electromagnets
  7. The quality of the stepper motor may also be a factor in any accuracy issues. 28BYJ-48 stepper motor Verses DC Motor and Servos. Some of the advantages of using the 28BYJ-48 over DC motors and servos include the following: Unlike DC motors and servos, the stepper motor is almost silent

28BYJ-48 Stepper Motor with ULN2003 + Arduino (4 Examples

The advantage of steppers over DC motors is that you can achieve much higher precision and control over the movement. The downside of using steppers is that they are a bit more complex to control than servos and DC motors. The 28BYJ-48 Stepper Motor Datasheet. The 28BYJ-48 is a small, cheap, 5 volt geared stepping motors The 28BYJ-48 stepper motor is widely used to control a myriad of common devices we see every day. From blinds, car side mirror tilts and DVD players to security cameras and precise control machines, stepper motors are closer to us than we actually think U LN2003 & 28BYJ-48 Stepper Motor — 7-ch Darlington Sink Driver — .6A@50v peak — Ardu-Serie#61 A dafruit Motor Shield v1 & v2 -4 DC Motors or 2 Stepper Motor or 2 Servos — 1.2A@25v & 3. 28BYJ-48-Stepper-Motor_2017-02-26_04.JPG. 4576KB. 2017/02/26. Description. Cheap and popular 28BYJ-48 stepper motor. This motor is common to many DIY and hobbyist projects. Comments. Submit. nice! 8 months ago. This looks good and was very helpful. However, I found that the shaft was not in the correct location. It was 7.857mm from the center.

28BYJ-48 Datasheet. Stepper motor is used for precision level controlling. The 28BYJ motor is a very common stepper motor and this can be used in various types of applications where precision control is required. The specification consists of 5V operating voltage and has a step angle of 5.625 degrees. Thus, 64 steps make 360 degrees of complete. In this video i will show you how to connect 28BYJ-48 5V DC Stepper motor with arduino & L293d motor shield and run on G-code stream via processing software. In this video we test various ways torque can be increased on the 28BYJ-48 stepper motor. We test the motor in unipolar and bipolar mode with ULN2003, L293D.

This mount fits Adafruit's 12V Small Reduction Stepper Motor (http://www.adafruit.com/products/918). Two mounting holes align with those of the BYJ48 Stepper Motor: Stepper Motor is a motor controlled by a series of electromagnetic coils. 28BYJ-48.pdf. Download. Add Tip Ask Question Comment Download. Step 2: Arduino Code . The Arduino IDE Support a Library for Stepper Motor , Very Easy to use , After Connect Motor with arduino You can Upload the Sketch on to the arduino

Arduino + 28BJY-48 Stepper Motor: Simple and Improved: I love these tiny 28BJY-48 stepper motors. They cost only a few dollars and have so many uses. They are compatible with Arduino, however the example code I have found online has either been overly complicated, or doesn't work quite right with the m Part Number : 28BYJ-48. Package : Module type. Function : 5V, Small Stepper Motor. Image : Description. Stepper Motor is a motor controlled by a series of electromagnetic coils. The center shaft has a series of magnets mounted on it, and the coils surrounding the shaft are alternately given current or not, creating magnetic fields which repulse. The 28BYJ-48 is out of the factory a Unipolar Stepper Motor which, nowadays, are not that common anymore. Bipolar stepper motors are considered to be at least twice as efficient as an Unipolar motor for the same amount of copper on the windings. According to research done by Jan Adriaensen the 28BYJ-48 in an Unipolar configuration can produce.

28BYJ-48 Stepper motors are really inexpensive and I have had been experimenting with them for some time. As-supplied they only have two attachments lugs that seem to be inconveniently positioned for most of the applications I want to try using them in. About this Motor One of the most common hobby stepper motors is the 28-BYJ48 (SUPER PROMO) US $1.69 6% OFF | Buy 28BYJ-48 DC 5V Reduction Step Gear Stepper Motor 4 Phase 28byj 28byj48 For Arduino Diy Kit From Merchant HWA YEH Experience Store. Enjoy Free Shipping Worldwide! Limited Time Sale Easy Return. Shop Quality & Best Stepper Motor Directly From China Stepper Motor Suppliers 28BYJ-48 RioRand-Motor. Da der RioRand-Motor eine größere Getriebeübersetzung hat, kann er mehr Drehmoment aufnehmen, ohne seine Position zu verlieren. Die Anwendung dieses größeren Drehmoments ist jedoch offensichtlich zu viel für die Zähne Sî yðÏhH ãqÓäÍ Í#1! È Sí¦ßJ¹I66±p‰k¾ E®+(F ö•øU # Œ{ör Sz #žmCØ (ʉû5I Àe©,šqä , ËVñ 3:©ž• R ( KΉ\ ¼o ¼5¨B°·‰×f(†%h7ß‚ 8ëêW± C ) ÉÁ³ ÿhA{ ßá`1¤Véù-çÀ «\ ÚÅRË †' A‚œ%ö j'äêH 7g+Ê ° ÔßmKcå0 Z[°² ´žaˆ¤æ Áeä6Bï­G€Ip•= ^þ:Í ÞPV. The 28BYJ-48 Stepper Motor is a motor controlled by a series of electromagnetic coils. The center shaft has a series of magnets mounted on it, and the coils surrounding the shaft are alternately given current or not, creating magnetic fields which repulse or attract the magnets on the shaft, causing the motor to rotate

28byj-48 stepper motor power consumption? Using Arduino. Motors, Mechanics, Power and CNC. ObiTewodros April 12, 2016, 6:47pm #1. I am using 6 1.5v AA batteries to power the stepper motor. The 6 batteries are only used to power the stepper motor. This is how I wired everything up: I use the custom stepper library from the following link:. ELEGOO 5 Sets 28BYJ-48 ULN2003 5V Stepper Motor + ULN2003 Driver Board Compatible with Arduino Visit the ELEGOO Store. 4.6 out of 5 stars 453 ratings | 59 answered questions Amazon's Choice highlights highly rated, well-priced products available to ship immediately US$7.99. Voltage: DC5V. Precise details>>. Precise details: 28YBJ-48 DC 5V 4 Phase 5 Wire Stepper Motor With ULN2003 Driver Board. Description: This is 28YBJ-48 DC 5V 4 phase 5 wire stepper motor with ULN2003 driver board. 5-wire phase can drive ordinary uln2003 chip can also be connected as phase 2 may be supporting the development board.

ステッピングモーター(28BYJ-48)の構造は「前回」で調べたので、駆動させる方法を中心に、ドライバーボードの必要性、回路図、配線時の注意、Arduinoの標準ライブラリを使って動かす方法を調べて検証します。 なぜドライバボードが必要なのか

The 28BYJ-48 is a small unipolar type stepper motor, and easy to integrate with Arduino, since it has a driver / controller module model ULN2003A that is usually included with it. All for a very cheap price and a fairly compact size 28BYJ-48 Stepper Motor. The 28BYJ-48 is a 5-wire uni-polar stepper motor that runs on 5 or 12 volts. The interesting thing about this motor is that people have been using it in countless applications over the last few decades. It is used in air-conditioner, vending machines and many other applications 28BYJ-48-5V Stepper Motor datasheet. ULN2003,04APG/AFWG 1 2010-12-03 TOSHIBA Bipolar Digital Integrated Circuit Datasheet. Sparkfun — Motors and Drivers Information about the 28BYJ-48 stepper motor and ULN2003 driver board The 28BYJ-48 is one of the cheapest stepper motors you can find. Although it is not super accurate or powerful, it is a great motor to use for smaller projects or if you just want to learn about stepper motors Stepper Motor 28BYJ-48 Horn by oscartprom: This motor horn fits perfectly on Adafruit's 12V Small Reduction Stepper Motor. Read more. Every Thursday is #3dthursday here at Adafruit! The DIY 3D printing community has passion and dedication for making solid objects from digital models. Recently, we have noticed electronics projects integrated.

We have used the 28BYJ-48 Stepper motor and the ULN2003 Driver module. To energise the four coils of the stepper motor we are using the digital pins 8,9,10 and 11. The driver module is powered by the 5V pin of the Arduino Board. A potentiometer is connected to A0 based in whose values we will rotate the Stepper motor Tiny stepper motor 28BYJ-48 control library for Arduino. Easy to use functions for controlling one or more 28BYJ-48 stepper motors. Uses speed and acceleration control for smooth operations and faster rotations. Requires a ULN2003 Driver Board. Author: S. Reifel The 28BYJ-48 Stepper Motor and ULN2003 Stepper Motor Driver is a widely popular combination of the stepper motor and stepper driver, because of the stability and reliability of the system. Thia 28BYJ-28 stepper motor is imported from one of our trusted suppliers and the supplier has guaranteed for the quality of these compact stepper motors

A 28BYJ-48 stepper motor connected to a ULN2003A driver board. A stepper motor divides a full rotation in multiple steps. As a result, a stepper motor can be driven much more precisely than a conventional dc motor. In particular, stepper motors are driven step by step. After having a quick look into the data sheet of a stepper, we know exactly. 28BYJ-48 Unipolar Stepper Motor (5v) As stated in the datasheet, the 28BYJ-48 motor has a step angle of 11.25°. That means there are 32 steps per revolution (360°/11.25° = 32). Note that this is a revolution of the main rotor, not the final shaft as this motor has an internal small gearbox Alibaba.com offers 1,233 28byj 48 stepper motor products. A wide variety of 28byj 48 stepper motor options are available to you, such as certification, phase, and usage

This small reduction 5-wire 28BYJ-48 stepper motor is a fantastic first stepper motor, great for experimenting with your raspberry pi and steppers. This uni-polar motor has a built in mounting plate with two mounting holes, and the motor shaft is flattened so it's easy to attach stuff with a set screw The stepper motor which I used in this project is 28BYJ-48, this motor equipped with speed reducer of 1/64.The internal motor has 32 steps per one revolution which means the external shaft has 2048 steps per one revolution (64 x 32) 28BYJ-48 Stepper motor holder and top plate. DOWNLOAD Thingiverse. Order Printed. English and Spanish Mini CNC Plotter With CNC SHIELD, Arduino and Step motor 28BYJ-28. DOWNLOAD Thingiverse. Order Printed. MiniArm - Small, Basic, Stepper-Motor Robot Arm. DOWNLOAD Thingiverse. Order Printed This entry was posted in Actuators, external video, Howtos, Raspberry Pi and tagged 28BYJ-48, python, Raspberry Pi, stepper motor on 2014-05-04 by paul. Post navigation ← ROS hydro materials to start Raspberry Pi Robot #1 28BYJ-48 - 5V Stepper Motor- from manufacturer 2D drawings. The Computer-Aided Design (CAD) files and all associated content posted to this website are created, uploaded, managed and owned by third party users

Stepper Motor with Driver (28BYJ-48 5V DC) « osoyoo

28BYJ-48 - Cookie Robotic

Driving Unipolar Stepper Motor (28BYJ-48) In our first experiment, we are using 28BYJ-48 unipolar stepper rated at 5V. It offers 48 steps per revolution. Before we start hooking the motor up with the chip, you will need to determine the A+, A-, B+ and B- wires on the motor you plan to use. The best way to do this is to check the datasheet of. 28byj 48 stepper motor with uln2003 control 28byj 48 stepper motor with control 28byj 48 stepper motor with with l29 motor driver ic arduino. 28byj 48 Stepper Motor With Uln2003 Arduino 4 Examples In Depth Control 28byj 48 Stepper Motor With Uln2003 Driver Arduin

Getting Started With Stepper Motor 28BYJ-48 - Arduino

  1. US$14.99 US$17.99 17% Off 20pcs ULN2003 Stepper Motor Driver Board Module for 5V 4-phase 5 line 28BYJ-48 Motor 0 review COD US$21.99 US$26.99 19% Off HANPOSE 17HS8401-D Double Shaft 48mm Nema 17 Stepper Motor 42 Motor 42BYGH 1.8A 52N.cm 4-lead for CNC Laser 3D Printer 3 reviews CO
  2. 28BYJ-48 Stepper Motor - 5V UnipolarThe most commonly used stepper motor is the 28BYJ-48-5V 4 Phase 5 Wire DC 5V Stepper Motor. You can find this (or similar) motors in your DVD drives, Motion camera and many more place. The motor has a 4 coil unipolar arrangement and each coil is rated for +5V hence it is relatively
  3. The Stepper class of the Arduino library follows a sequence of 4 values of 4 bits but the 28BYJ-48 requires a sequence of 8 values of 4 bits. One step of the motor correspond to 1 value of the sequence. Those 8 values must be repeated in this order to turn the motor in one direction and in the reverse order to turn the motor in the other direction
  4. 3D design 28BYJ-48 stepper motor created by jackjansen with Tinkerca
  5. 28BYJ-48 Stepper Motor adalah sebuah motor stepper 4 phase dengan tegangan supply sebesar 5V. Motor Stepper ini ideal digunakan dalam berbagai aplikasi elektronika seperti pembuatan robot, remote control dan perangkat lainnya yang membutuhkan suatu motor yang stepnya dapat diatur secara tepat. Berikut adalah spesifikasi dari 28BYJ-48 Stepper Motor : Supply Tegangan: 5VDC Jumlah Phase 4
  6. Joystick and 2 28YBJ-48 stepper motors. Since I have 2 little stepper motors and a joystick I thought it would be nice to see if I could write a sketch that would let me control them with the joystick. I first connected the little stepper motors and ran an example sketch I found here to see if they were working

The stepper motor which I used in this project is 28BYJ-48, this motor is equipped with speed reducer of 1/64. The internal motor has 32 steps per one revolution which means the external shaft has 2048 steps per one revolution (64 x 32). Number of steps is defined in the code as shown below US$5.99 US$7.99 25% Off ULN2003 Stepper Motor Driver Board Module for 5V 4-phase 5 line 28BYJ-48 Motor Geekcreit for Arduino - products that work with official Arduino boards 11 reviews COD US$15.99 US$19.99 20% Off 10pcs 5mm x 8mm Aluminum Flexible Shaft Coupling OD19mm x L25mm CNC Stepper Motor Coupler Connector 17 reviews CO Stepper motor 28BYJ-48. This is the English version of this earlier blogpost. Also check this blogpost on how to change the motor into a bipolar model with a lot more torque. This must be the cheapest stepper motor I know. I guess the reason why it's so popular among hobbyists is simple: its price

Arduino Projekte

Change unipolar 28BYJ-48 to bipolar stepper motor. Now here's something I was not expecting. Previously, I tried to drive this stepper motor with the driver board that came with the motor. My main goal was of course keeping the accuracy of the tiny motor safe and then testing at which speed I could get the maximum torque it could produce Which motor is slower than (and can be swapped with) a 28BYJ-48 stepper motor? 1. What type of 2-pin connector is this? 1. Controlling multiple stepper motors using a single driver. Hot Network Questions Interesting answer as a range of tension in pulley-block-plane syste Diymore 5pcs DC 5V 28BYJ-48 Valve Gear Stepper Motor 4 Phase Stepper Motor. $10.99. $10. . 99. Get it as soon as Fri, Jul 9. FREE Shipping on orders over $25 shipped by Amazon. Only 2 left in stock - order soon On top of the carriage is a 28BYJ-48 bipolar. This stepper only needs to perform a very simple 180° rotation upon the push. of a reliable button #2. Here is a summary of the sequence I hope to achieve: NEMA23: Bipolar stepper motor, (4 lead) 2.8 Amp per phase,. Motion is provided by a 28BYJ-48 stepper which is connected to the drive nut by way of a belt. The spinning nut is used to raise and lower the threaded rod which opens and closes the door

El 28BYJ-48 es un pequeño motor paso a paso unipolar de bajo precio. Las características eléctricas del 28BYJ-48 son modestas, pero incorpora un reductor integrado que lo convierte en un componente mucho más útil e interesante. El 28BYJ-48 tiene un paso de 5.625 grados (64 pasos por vuelta). El reductor interno tiene una relación de 1/64 En esta sesión, vamos a usar un pequeño motor paso a paso unipolar, muy común en el mundo Arduino por su pequeño tamaño y bajo coste, el 28BYJ-48 y el adaptador que suele venir con él, basado en el chip ULN2003A. Veremos en primer lugar las características que presenta y después montaremos un pequeño circuito básico, para mover el motor

28BYJ-48 Stepper Motor Pinout and specification

Conexión del motor paso a paso 28BYJ-48 y el módulo ULN2003 con Arduino. En este artículo veremos el motor paso a paso unipolar 28BYJ-48. Es un motor barato y que podemos utilizar en gran cantidad de proyectos como robots, impresoras 3D o fotocopiadoras. Nos vamos a centrar en la programación del motor con Arduino y su conexión 幾乎所有的Arduino學習套件裡,都會有ULN2003+28BYJ-48步進馬達這樣的組合,什麼是步進馬達(Stepper motor)?簡單來說,就是這個馬達可以依我們的指示,精準的旋轉一定的角度,最常被運用在3D列印機之類的設備上

Control 28BYJ-48 Stepper Motor with Arduino

28BYJ-48 - Stepper Motor ( 5V ) The 28BYJ-48 is a small stepper motor suitable for a large range of applications. This features is Wire leads with connector, Unipolar coil type, Permanent magnet gear motor. Stepper Motor is a motor controlled by a series of electromagnetic coils. The center shaft has a series of magnets mounted on it, and the. Story. This project is an easy introduction to stepper motors and aims to introduce null-level beginners to stepper motors and their respective drivers. This project used 28byj-48 stepper motor and UNL-2003 stepper motor driver. This project is based on the arduino UNO microprocessor Driving Stepper Motors (28BYJ-48) August 11, 2018 XTronical Basics, Motors 2. A supporting video is available for this article : Brief Introduction to Stepper Motors. A stepper motor behaves just like a normal motor in so much that it has a rotating shaft but that's where the similarity mostly ends. When hooked up to some sort of controlling.

28BYJ-48 Stepper Motor With Driver Code For Arduino

Modifying a 28BYJ-48 step motor from unipolar to bipolar I have always liked the 28BYJ-48 motor because of its power and price, it also supposed to very reliable since it is used in different types of air conditioners. This step motor comes in 5V and 12V flavours. Some information about the motor This 28BYJ-48 is a 5V unipolar geared stepper motor, manufactured by the boatload for the HVAC control industry, where you'll find these little units as actuators for airflow control in ducts and vanes. It features a 5mm Double-D shaft, mounting lugs, and a nice 5-conductor 0.1″ pitch connector. The gearing isn't the beefiest or. This entry was posted in Actuators, Raspberry Pi and tagged 28BYJ-48, python, Raspberry Pi, stepper motor on 2014-05-06 by paul. Post navigation ← Raspberry Pi Robot #1 Raspberry Pi Robot with ROS, Xtion, OpenNi2 and rviz providing 3d point cloud data DC 5V Stepper Motor 28BYJ-48 Sehr geehrter Kunde, vielen Dank, dass Sie sich für unser Produktentschieden haben. Im Folgenden haben wir aufgelistet, was bei der Inbetriebnahme zu beachten ist: Verwendung mit einem Arduino Schritt 1 - Anschließen des Motors Bild 1: 28BYJ-48 mit Treiber-Boar Il modello 28BYJ-48 non identifica una specifica versione di motore, ma ci sono diversi motori stepper con diverse caratteristiche ma stessa sigla. Questo Il motore ha il seguente aspetto: Nel seguente articolo vengono mostrate le caratteristiche elettriche e le caratteristiche meccaniche, illustrando inoltre la sequenza di controllo del motore

28BYJ-48 Stepper Motor with ULN2003 driver and Arduino Uno

Ich habe günstig zwei Schrittmotoren des Typs 28BYJ-48 inkl. einem Treiberboard auf Basis des ULN2003 erstanden. Hier folgt eine Anleitung, wie man diesen Motor problemlos mit der Arduino Stepper Library betreiben kann. An vielen Stellen im Netz liest man, dass das nicht geht und findet diverse hangestrickte Codes, umgebaute Libs etc. Der ganze Aufwand ist [ El motor 28BYJ-498 es un motor paso a paso que tiene las siguientes características: Tipo: motor paso a paso o stepper unipolar. Fases: 4 (full step), al haber 4 bobinas en su interior. Resistencia: 50 Ω. Par de motor: 34 N/m, es decir, si se pasan los Newton por metro a Kg, sería una fuerza equivalente a poner unos 0.34 Kg por cm en su eje Control two 28BYJ-48 stepper motors with a joystick. Follow the circuit diagram for all connections. You will have to also connect both of the stepper driver modules to a 9v battery

How to use Arduino as a 28BYJ-48 Stepper Motor Controller

28BYJ-48 Stepper Motor with ULN2003 and Arduino (4 Examples) says: September 8, 2019 at 5:50 pm [] Control a stepper motor with L298N motor driver and Arduino [] Primary Sidebar. Search this website. Footer. How to control a Stepper Motor with Arduino Motor Shield Rev3 Simple Stepper Motor 4-Phase 5-Wire with ULN2003 Driver. Overview Operating system. Mbed OS. The open source OS for Cortex-M devices. Development tools. Users » lasmahei » Code » StepperMotor_28BYJ-48. Martin Heine / StepperMotor_28BYJ-48 Simple Stepper Motor 4-Phase 5-Wire with ULN2003 Driver. Dependencies: mbe The 28BYJ-48 Stepper Motor. The 28BYJ-48 is a 5-wire unipolar stepper motor. As with most motors, the power required is too much to pull directly from an Arduino, so a separate power supply is required but with a common ground. The 28BYJ-48 or similar steper motors are available from multiple sources, and there are two important things to note

Arduino & stepper 28byj-48Making XY Plotter using Arduino UNO and 28BYJ-48 stepper

28BYJ-48 Stepper motor is one of these motors. This motor consists of 4 stationary coils and has a 64:1 gear reduction. This motor has 5 wires. The red one is connected to a 5V power supply and others are for each stationary coils. Pull in torque: 300 gf.cm Stepper Motor (28BYJ-48) 28BYJ-48 is a Unipolar Stepper motor which requires 5V supply. The motor has a 4 coil unipolar arrangement and each coil is rated for +5V hence it is relatively easy to control with any microcontrollers like Arduino ,Raspberry Pi also STM32.But we need a Motor Drive IC like ULN2003 to drive it, because stepper motors consume high current and it may damage microcontrollers Thus a 5v motor can be run on 12v or even 13.8v as often used in observatories and provided by a nominally 12v car or pleasure battery. With this modification and A4988 stepper motor controller with micro-stepping, finer control can be provided from a 28BYJ-48 stepper motor used in a remote focussing system. Here are some photos : 28BYJ-48 stepper motor. Thread starter voso; Start date Feb 3, 2021; Feb 3, 2021 #1 V. voso Newbie. Joined Feb 3, 2021 Messages 3 Helped 0 Reputation 0 Reaction score 0 Trophy points 1 Activity points 26 I have a 135mm diameter turntable for models. powered by the 28BYJ-48 stepper motor using a 5v transformer. I have set the unit to rotate. I am trying to use Arduino MEGA 2560 test a 28BYJ-48 stepper motor, that works on Arduino UNO on PIN 8/9/10/11? The motor doesn't turn when I change the drive pin to PIN 20/22/24/26 on NEGA2560? why? Wiring drive pin to IN1/2/3/4 in turn. Thanks Adam /* Stepper Motor Control - speed control..