Components

	TPS61040DDCR Texas Instruments	x 1
	DRV8434EPWPR Texas Instruments	x 1
	BH-18650-PC MPD	x 1
	Arduino Nano V3	x 1
	Mini Breadboard	x 2

Tools, APP Software Used etc.

arduino IDE

Arduino

Description

DRV Driver Rc Car Pcb

About the driver

At the heart of the DRV8825 driver, you will find a chip made by Texas Instruments: the DRV8825 Stepper Motor Controller IC. This integrated motor driver makes interfacing with a microcontroller super easy as you only need two pins to control both the speed and the direction of the stepper motor.

The driver has a maximum output capacity of 45 V and ± 2 A which is great for driving small to medium-sized stepper motors like a NEMA 17 bipolar stepper motor.

If you need to control larger stepper motors like a NEMA 23, take a look at the TB6600 stepper motor driver. This driver can be used with the same code as the A4988 and has a current rating of 3.5 A.

The DRV8825 driver chip has several safety functions built-in like overcurrent, short circuit, under-voltage lockout, and over-temperature protection

Microstep settings

Stepper motors typically have a step size of 1.8° or 200 steps per revolution, this refers to full steps. A microstepping driver such as the DRV8825 allows higher resolutions by allowing intermediate step locations. This is achieved by energizing the coils with intermediate current levels.

For instance, driving a motor in quarter-step mode will give the 200-step-per-revolution motor 800 micro steps per revolution by using four different current levels.

DRV8825 Pinout

The resolution (step size) selector pins (M0, M1, and M2) allow you to select one

Writing a device driver requires an in-depth understanding of how the hardware and the software works for a given platform function. Because drivers require low-level access to hardware functions in order to operate, drivers typically operate in a highly privileged environment and can cause system operational issues if something goes wrong.

In contrast, most user-level software on modern operating systems can be stopped without greatly affecting the rest of the system. Even drivers executing in user mode can crash a system if the device is erroneously programmed. These factors make it more difficult and dangerous to diagnose problems

DIR: This is the pin which controls the direction of the rotation of the motor. This will also be connected to a digital pin of the Arduino. When a high signal is passed to this pin, the motor will rotate clockwise whereas if a low signal is provided instead, the motor will rotate in an anti-clockwise direction.

Connect the output pins of the driver with the respective motor pins. Connect the STEP pin and the DIR pin with any appropriate digital pin of the Arduino board. We have used digital pin 6 to connect with DIR and digital pin 7 to connect with STEP. As we want to operate our stepper mode in full mode hence we will leave the M0, M1, and M2 pins as they are.

The RST pin and the SLP pin will be connected with 5V from Arduino so that the driver is enabled. Moreover, the logic GND pin will be connected with a GND pin from Arduino. The VMOT will be connected with an external power supply ranging between 8.5-45V. We are using a 12V external power supply. Make sure the GND pins are connected with the respective common grounds.

Additionally, we can also add a capacitor(minimum 100uF) with the external power supply connected with the stepper motor power supply pins to avoid voltage spike issues.

EN: This is the enable pin. It is used to turn the outputs of the module on or off. A high signal will disable the outputs. By default, the pin is at a low state.

RST: This is the reset pin. It sets the internal translator to a predefined Home state which is the position where the motor starts initially. This position will vary depending upon the microstep resolution. This is an active low input where a HIGH signal will enable the driver.

SLP: This is also an active low input pin which is used to reduce power consumption by setting the module to sleep mode when the motors are not in use. This is achieved by supplying a low signal to this pin.

Code

code

C/C++

const int dirPin = 2;
const int stepPin = 3;
const int stepsPerRevolution = 200;

void setup()
{
	// Declare pins as Outputs
	pinMode(stepPin, OUTPUT);
	pinMode(dirPin, OUTPUT);
}
void loop()
{
	// Set motor direction clockwise
	digitalWrite(dirPin, HIGH);

	// Spin motor slowly
	for(int x = 0; x < stepsPerRevolution; x++)
	{
		digitalWrite(stepPin, HIGH);
		delayMicroseconds(2000);
		digitalWrite(stepPin, LOW);
		delayMicroseconds(2000);
	}
	delay(1000); // Wait a second
	
	// Set motor direction counterclockwise
	digitalWrite(dirPin, LOW);

	// Spin motor quickly
	for(int x = 0; x < stepsPerRevolution; x++)
	{
		digitalWrite(stepPin, HIGH);
		delayMicroseconds(1000);
		digitalWrite(stepPin, LOW);
		delayMicroseconds(1000);
	}
	delay(1000); // Wait a second
}

Schematic and Layout

schematics

Screenshot (396).png