PIC16F877 interface to 2 unipolar stepper motors

[denis_b]

i need help in designing a circuit to control 2 unipolar stepper motors using PIC uC. any suggestions on what driver to use, i am planning on using ULN2803..feel free to suggest anything otherwise.

Please help

 

[ivancho]

If you check out www.st.com and check the L297 and L298 ICs you will see how easy and fast si to implement a stepper driver... they also have an application note on how to connect them both and interface them with a microcontroller as to save the most I/O lines.

The current used by the stepper must be considered since driver will need to handle this current, and therefore you might need to find a h-bridge or half drive that will work.... since it is unipolar you are going to drive it only in one direction, and therefore you will need only a half drive.

Ivancho

 

[falleafd]

You can easily build a circuit for unipolar stepping

with ULN2003 or ULN2803, they are the same. I describe connections with ULN2003, you can make it with UL2803 in the same way, but look at the datasheet, you can drive 2 motors with 2803

You need 4 inputs (pins 2 - 5) and 4 outputs (pin 15 - 12) alternatively

5 VDC (VDD of control voltage) should be connected to pins 1,6,7,8
12 VDC (power supply for the motor) should connect to the centre wires of stepping

a 15V zener (depends on your motor). If you motor is 24 VDC or 12 VDC, it will work. the zener will be connected from power supply to pin 9

Others should be connect to 5VDC via a resistor (1K, I guess).

Good luck.

You may search for SMACK project on internet for understanding 2803.

They used 16C73 for 3 motors. One is used with 2003, two others are used with 2803.

In my circuit, I don't leave any pin free. You can pull it up to VDD or pull it down to GND, upto you, or you may leave unused pins free...

goodluck.

 

[TKS]

bipolar

does have anybody also a good site of interface example for a bipolar stepper motor...??

TKS

 

[falleafd]

For bipolar motors, we usually find the interfaces out at some H bridges providers.

You make take a look for L298 datasheet, and you will see how to interface a bipolar motor.

And it also provide some higher level driver, such as L297.

Goodluck

 

[iceman777]

PLS help

Hi all

I am trying to get hold of a circuit diagram with connections between the PIC16F877, ULN2803 and two stepper motors. If any one could post a link or e-mail me a diagram i would really appreciate it. My e-mail: mynhardt34@googlemail.com

Thanks

 

[House0Fwax]

I am trying to get hold of a circuit diagram with connections between the PIC16F877, ULN2803 and two stepper motors.

http://www.geocities.com/vsurducan/electro/PIC/f877.html
f877 free experiment

 

[iceman777]

Thanks

Thanx 4 the help.

The circuit diagram is really useful, and makes everything seem simple.

Thanks once again
Iceman

 

[falleafd]

http://www.st.com/stonline/books/pdf/docs/1334.pdf

Someone asked me on the email about L297 and L298. This is the useful link. The PIC will be connected to the L297 (the higher level driver) and the motor is connected to the outputs of L298.

Pls read the tutorial on Stepping motors of Douglas W. Jones.

And if you are Vietnamese, pls read the translated version at www.picvietnam.com (I have the right of Douglas W. Jones to translate this)

The link is: http://www.picvietnam.com/forum//showthread.php?t=44

Goodluck.