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General Category => General Discussion => Topic started by: bobz on March 26, 2012, 22:41:40 PM

Title: PIC Controlled Motor
Post by: bobz on March 26, 2012, 22:41:40 PM
Does anyone have any ideas on how one could control a small tape cassette motor with a PIC?

My project requires me to change the direction of the motor (by changing polarity of course) when a momentary switch is pressed.

A short delay between changes is more than acceptable.

Any ideas are greatly appreciated.

If you need any more info on the project just ask :-)


Title: Re: PIC Controlled Motor
Post by: kam on March 27, 2012, 08:39:37 AM
usually people use a H-bridge for this, but also a 2p2t relay can work as well. A PIC to control the h-bridge or the relay is a good idea. do you have some kind of programming skills for PICs?
Title: Re: PIC Controlled Motor
Post by: bobz on March 27, 2012, 23:45:19 PM
Hi KAM.  Thanks for replying to my post.  No real experience with programming.  Just simple electronics.  The most complicated electronics i have worked with (and a lot with) are high power amplifiers and analogue audio mixers.

I had thought of using a relay but wanted to gain some knowledge with PICs and what better way than to use them right?!

I wanted to stay away from using relays as the project will have to be as low profile as possible. Maybe an 8-Bit to keep it small.  Also don't have more than maybe 5VDC on batteries with a constant drain @ 500ma of 5900-6800mAh.

Also considered a H-bridge but without knowing exactly what PICs were capable of decided to quiz people who know about it.

Could I combine the two and use two of the outputs form the PIC to trigger between the 'A set of transistors' and 'B set of transistors' in the H bridge. 

Could this work?

I know the programming would be relatively simple but is there anything i haven't thought of?

Title: Re: PIC Controlled Motor
Post by: kam on March 29, 2012, 12:37:09 PM
The application you want to do is simple, and when it comes to PIC (or other microcontrolelr) it is really very very simple. It can of course control a h-bridge easily. The only problem you may come up with is if the motor draws lot of current and generates noise to the power line, so the PIC will go crazy. But that can be solved with a filter.

If you think that you have some time to "invest" in microcontroller learning, i can only tell you that you will not regret it. You need to spend some time though to start working with m/cs. It is not as simple as plug'n'play.
Title: Re: PIC Controlled Motor
Post by: bobz on March 29, 2012, 22:07:49 PM
The Motor is a very low powered tape cassette motor which has very low torque and will be running through a speed reducing gear.  I've figured out how to control the H-Bridge with a latch circuit so can do that for now.  but i think i will invest in the gear to work with PIC's as i can see a lot of potential with them. 

Are there any projects you could recommend for a beginner like me?

Thanks for all your help. I will no doubt be a regular visitor to this site.  in fact, if it wasn't for Giorgos' youtube videos i wouldnt know about it lol.

Thanks a lot and i hope i can contribute to this site.

Title: Re: PIC Controlled Motor
Post by: kam on March 30, 2012, 08:11:04 AM
well, i have some sort of "tutorials" in this page:


but i never finished it, because in the way i changed the method i present things. It has some good and simple tutorials to show how you can start with PICs thought.
Title: Re: PIC Controlled Motor
Post by: bobz on March 30, 2012, 22:44:44 PM
Ok thanks.  I'll get started As soon as i can. 

Thanks Kam youve been a great help.  can see why your a hero member.

Take care.

reagards, Robert