Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: darkjungle on August 15, 2007, 10:29:51 AM

Title: motor connections with L298
Post by: darkjungle on August 15, 2007, 10:29:51 AM

how to programme to slow down the speed of motoer using a l293 motor ic.what programme to be written?

Title: Re: motor connections with L298
Post by: Steve Joblin on August 15, 2007, 12:16:00 PM

The L293 can only control direction... to control speed you need to "pulse" the signal off and on very quicly... The technique is called Pulse Width Modulation, or PWM for short.  Many microcontrollers have a PWM command that will make it very easy to do.

For examples of how you do it with a Parallax Basic Stamp, check out this link (the code is at the bottom of the page)... http://www.me.umn.edu/courses/me2011/robot/technotes/L293/L293.html

Title: Re: motor connections with L298
Post by: elixier on August 15, 2007, 12:28:51 PM

The only thing you have to do is to generate A Pulse Width Modulated Signal with the help of the Program and feed it to the Control input of the L293 for the Clockwise or the Anticlockwise direction.

The PWM Signal generated by the Microcontroller can help in slowing or controlling the speed of the Motor.
look for following links.
http://www.societyofrobots.com/schematics_h-bridgedes.shtml
http://www.societyofrobots.com/member_tutorials/node/33

Title: Re: motor connections with L298
Post by: darkjungle on August 17, 2007, 05:39:05 AM

How should be the motor driver like l298 be connected to armega 8.Where should the 4 input pins be connected to atmega 8.

Title: Re: motor connections with L298
Post by: black-code on August 19, 2007, 06:07:14 PM

U can use l298, with it u can control both the speed and the direction and it's good too when interfacing motors with microcontrollers.

the speed can be controlled by PWM (pulse width modulation).

Black-Code

Title: Re: motor connections with L298
Post by: Admin on August 21, 2007, 03:11:23 PM

Quote

How should be the motor driver like l298 be connected to armega 8.Where should the 4 input pins be connected to atmega 8.

The ATmega8 has a multitude of digital output pins. On my $50 robot you will notice the servos connected to some pins. You can connect the l298 in the same way.

For example use pins PD0, PD1, PD2, and PD3.

$50 robot schematic for reference
http://www.societyofrobots.com/images/sbs_avr_schematic.png

Title: Re: motor connections with L298
Post by: Hal9000 on August 24, 2007, 02:00:48 PM

http://images.google.com/images?source=ig&hl=en&q=l298&um=1&sa=N&tab=wi (http://images.google.com/images?source=ig&hl=en&q=l298&um=1&sa=N&tab=wi)

There ya go