PWM DIES when I try to use LCD display

Hi all,

Newbie here.

I am trying to put together what I thought was a simple task.

it has two main parts

  1. a PWM driving a DC brushed motor. That part was very simple.

  2. an LCD display that would show the set point of the PWM motor and then display the Current/Load on the motor.

I have a 1 ohm resistor on the motor and I am reading the voltage across that. This I will display on the LCD.

I have the motor running and I have the LCD running but when I try to work the two together, the motor dies.

It appears that trying to write to the LCD and at the same time run the motor creates the problem.

I can explain this further or show the code if anyone has interest.

I really need to solve this one.

If I can not solve it I will have to use a seperate display that is not linked to the motor drive but I prefer to do it this way as it makes the whole thing more simple.

Help me Help me Help me… :neutral:

steveinboston:
I can explain this further or show the code if anyone has interest.

I really need to solve this one.

If I can not solve it I will have to use a seperate display that is not linked to the motor drive but I prefer to do it this way as it makes the whole thing more simple.

Might be a heck of a lot more helpful to see some code and a circuit.

For all anybody knows, you’re programming for an ENIAC and using a monkey to turn a motor.

Help me Help me Help me… :neutral:

Ok...

http://www.catb.org/esr/faqs/smart-questions.html

Hi Steve,

I’ll put a second pair of eyes on it if you bring your setup to the asylum. Maybe I put you off ,but I’m a nice guy and like to help, as do many others there if we’re stumped.

-Seth

How is the resistor connected to the motor? high side or low side?

When you say “I have the motor running and I have the LCD running but when I try to work the two together, the motor dies. It appears that trying to write to the LCD and at the same time run the motor creates the problem” … what is it you’re doing, exactly ?

Do you have 2 separate sketches, each of which runs and works or do you have 1 integrated sketch that works when you have the LCD attached or when you have the motor attached, but not with both attached ? Because if it’s the latter the software really doesn’t “know” what’s attached … there’s no communication from the motor or the LCD to the Arduino. This would tend to tell me you have some hardware issue, probably with how you’re supplying power to both items.