Test with Nema 17 and DRV8825.

[Fermin]

Hello.
I’m building a 172 Cesnna cab, with a 17" monitor. And I need to build a compass with a Stepper.
I’m running a test run on the Nema 17 and the DRV8825 driver (equivalent to A4988).
I’ve been looking at all the threads on the forum, and I’ve used the VID66-06 option. But I haven’t got the engine moving.

With this simple code in Arduino, I can make the stepper turn clockwise or counterclockwise, depending on an optocoupler:

const int dirPin = 2;
const int stepPin = 3;
const int optoini = 4;
int optoinivalue = HIGH;
const int stepsPerRevolution = 200;
void setup()
{
// Declare pins
pinMode(stepPin, OUTPUT);
pinMode(dirPin, OUTPUT);
pinMode(optoini, INPUT);
}
void loop()
{
// Set motor direction
optoinivalue = digitalRead(optoini);
if (optoinivalue == HIGH) {
digitalWrite(dirPin, LOW); //Set motor direction clockwise
}
else {
digitalWrite(dirPin, HIGH); //Set motor direction anticlockwise
}

// Spin motor
for(int x = 0; x < stepsPerRevolution; x++)
{
digitalWrite(stepPin, HIGH);
delayMicroseconds(300);
digitalWrite(stepPin, LOW);
delayMicroseconds(700);
}
}

Does anyone have a test LUA script that they can use in Airmanager?

I’m expecting to receive a 28BYJ-48/ULN2003, but in the meantime, I want to test the Nema17.

Thanks.

[jph]

Where and why are you using an optocoupler ???

[jph]

checkout - https://www.makerguides.com/drv8825-ste ... -tutorial/

the basic wiring and info for the 8255
then look at the vid 066 example - https://siminnovations.com/wiki/index.p ... VID66-06_2

That is all you should need. Just set the appropriate pins on the 8255 (RES, SLEEP, EN, M1, MX, MY etc ( microstep)) before applying the vid 066 code and you only need step and direction.
Joe

[Fermin]

Thanks jph.

I have no problem using the stepper with Arduino. As I explained earlier, with that Arduino script I can totally control the Stepper.

I’ve already discovered where the problem is. The problem is AirManager. If you use pins 2 and 3, the Stepper doesn’t work. Now I’m using pins 5 and 6 and it already works perfectly.

This Wiki script does not work with Arduino Mega2560:

id = hw_stepper_motor_add("VID66-06", 200, 10, true, "ARDUINO_MEGA2560_A_D2", "ARDUINO_MEGA2560_A_D3")
-- Set position
hw_stepper_motor_position(id, 0.5)

Instead, this modified script, works on Arduino Mega2560:

id = hw_stepper_motor_add("VID66-06", 200, 10, true, "ARDUINO_MEGA2560_A_D5", "ARDUINO_MEGA2560_A_D6")
-- Set position
hw_stepper_motor_position(id, 0.5)

Someone should correct the Wiki example of VID66-06.

Now I can continue to build my cabin.
Thanks again.

[Ralph]

The pins don't matter, you can choose any pin you want, except for D0 and D1.

[jph]

Hi @Ralph
It seems strange that he has it working though - but not on pins D2 and D3 ?

[Ralph]

There are problems with the VID control in 4.0.x anyway, so that's probably what you're seeing. It is better to use the beta, should be working in the beta.

[Ralph]

I can't get our VID to work somehow, but the sequence does not change if I select D2 and D3, or D5 and D6, they are exactly the same.