Hi,
I have the same motorshield from adafruit:
For now the motor shield can control up to 4 DC motors, but I need to control two more DC motors. As I know the shield is using 4 PWM signals from 4 out of 6 PWM output pins from the Arduino Uno. Is there anyway we can use the other 2 remaining PWM to control 2 motors using an additional H-bridge circuit?
MotorShield with PWM
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- adafruit_support_bill
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Re: MotorShield with PWM
There are a couple of approaches to this:
If you do not need direction control for some motors, those motors can be controlled with just a PWM pin and a transistor.
If you do need both direction and speed on all motors, you could hook up another H-bridge chip with some of the unused pins. Or you could look into some of the serial motor control modules from Pololu.
If you do not need direction control for some motors, those motors can be controlled with just a PWM pin and a transistor.
If you do need both direction and speed on all motors, you could hook up another H-bridge chip with some of the unused pins. Or you could look into some of the serial motor control modules from Pololu.
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Re: MotorShield with PWM
Which PWM pins on the Arduino will connect to the Servo pins on the shield? Are they pin 9 and 10?
- adafruit_support_bill
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Re: MotorShield with PWM
Yes. 9 & 10 are the servo pins.
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Re: MotorShield with PWM
Great, I am using L293d H-Bridge. 2 PWM signals from the Servo will go to pin 1(EN) and Motor Logic 2A (pin 7), I still need one digital pin which will go to Motor Logic 1A (pin 2). I guess I can use pin 4,7,8 or 12 from the Arduino, but I don't know how they are connected to the shield. In other words, I want to know which pins on the shield are connected to pin 4,7,8,12 on the Arduino?!
Thanks!
Thanks!
- adafruit_support_bill
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Re: MotorShield with PWM
It's in the FAQ: http://learn.adafruit.com/adafruit-motor-shield/faqIn other words, I want to know which pins on the shield are connected to pin 4,7,8,12 on the Arduino?!
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Re: MotorShield with PWM
Hi:
Would it be correct to assume that all motors, DC and Stepper, must use the save voltage? For instance I couldn't use a 24 V power supply and a 24 volt motor and a 6 volt motor?
Or is there a way one could do this?
Z
Would it be correct to assume that all motors, DC and Stepper, must use the save voltage? For instance I couldn't use a 24 V power supply and a 24 volt motor and a 6 volt motor?
Or is there a way one could do this?
Z
- adafruit_support_bill
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Re: MotorShield with PWM
@Zenock: All would need to use the same voltage.
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Re: MotorShield with PWM
Could I cut the lead to PIN 8 on one of the chips and wire in a voltage regulator?
Also, If I understand correctly, the servos runs off 5 V even if I'm running the motors off 24 volts? Is this correct?
Also, If I understand correctly, the servos runs off 5 V even if I'm running the motors off 24 volts? Is this correct?
- adafruit_support_bill
- Posts: 88142
- Joined: Sat Feb 07, 2009 10:11 am
Re: MotorShield with PWM
Yes. That is possible.Could I cut the lead to PIN 8 on one of the chips and wire in a voltage regulator?
Normally true. Although a separate supply for servos is possible as described in the FAQ: http://forums.adafruit.com/viewtopic.php?f=31&t=26873Also, If I understand correctly, the servos runs off 5 V even if I'm running the motors off 24 volts? Is this correct?
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- Joined: Tue Mar 12, 2013 7:06 pm
Re: MotorShield with PWM
Thank you so much. You are AWESOME.
Please be positive and constructive with your questions and comments.