NXP Application Code Hub

Servo Steering Control Using PWM

This application implements a real-time steer-by-wire concept on the FRDM-A-S32K344 evaluation board. A POT Click potentiometer provides an analog steering-wheel input that is sampled via ADC0 , scaled to angular position, and converted into a PWM duty cycle that drives a Micro Servo SG 180° motor through a Servo Click board controlled over LPI2C1.
On startup the servo centers to its neutral position; as the potentiometer is rotated the servo smoothly tracks the angle in real time, closing the full signal chain from analog acquisition → signal processing → actuator control.
The project is built with the S32K3 Real-Time Drivers (RTD) for ADC, I2C, and GPIO peripherals, and is configured entirely within S32 Design Studio IDE — making it a practical reference for PWM-based motor control and sensor-to-actuator mapping in automotive prototyping.

Boards: FRDM-A-S32K344

Categories: Sensor

Peripherals: I2C, PWM, ADC

Toolchains: S32 Design Studio IDE

Table of Contents

1. Software and Tools
2. Hardware
3. Setup
4. Results
5. Support
6. Release Notes

1. Software and Tools

This example was developed using the FRDM Automotive Bundle for S32K3 + S32M27. To download and install the complete software and tools ecosystem, use the following link:

• FRDM Automotive S32K3 + S32M27 Board Installation Package

2. Hardware

2.1 Required Hardware

• Personal Computer
• Type-C USB cable

Boards	Images
- FRDM-A-S32K344
- FRDM K64 click shield
- Servo Click - POT Click
- Micro Servo motor SG 180 degree

2.2 Hardware Connections

FRDM-A-S32K344	Header Pin	I/O	FRDM Shield	Click Board	Click Pin	Description
PTB17 GPIO, 49	J2 pin 5	→	D10	Servo Click	OE	Output Enable
PTC6 LPI2C1_SDA	J2 pin 17	→	SDA	Servo Click	SDA	I2C SDA Pin
PTC7 LPI2C1_SCL	J2 pin 19	→	SCL	Servo Click	SCL	I2C SCL Pin
P5V0 power 5V	JA3 pin 11	→	5V power	Servo Click	5V	VCC MOT move 0ohm to 5V
PTD0 ADC0_P1	J4 pin 3	←	A1	POT Click	AN	Analog Output
GND	JA3 pin 11	→	GND	POT Click	GND	Ground
VDD_PERH	JA3 pin 7	→	3.3V	POT Click	3V3	3.3V Power

Note: The Servo Click motor can be powered in two ways:

• External Power (default): Connect an external 5V power supply to the Servo Click's VCC MOT terminal — no hardware modification is needed.
• Board Power: Move the VCC MOT 0Ω resistor from the EXT position to the 5V position on the Servo Click board. This allows the servo motor to be powered directly from the FRDM-A-S32K344 board's 5V rail, eliminating the need for an external power supply.

The Servo motor is connected to the Servo Click on the channel 1, folowing table:

Servo Click	Servo Motor
GND	Brown Wire
VCC	Red Wire
PWM	Orange Wire

2.3 Debugger Connection

• Connect the Type-C USB cable to PC and FRDM-A-S32K344 board for power supply and debugging

3. Setup

3.1 Import the Project into S32 Design Studio IDE

1. Open S32 Design Studio IDE, in the Dashboard Panel, choose Import project from Application Code Hub.

   

2. You can find the demo you need by searching for the name directly. Open the project, click the GitHub link from this window, S32 Design Studio IDE will automatically retrieve project attributes then click Next>.

   

3. Select main branch and then click Next>.

4. Select your local path for the repo in Destination->Directory window. The S32 Design Studio IDE will clone the repo into this path, click Next>.

5. Select Import existing Eclipse projects then click Next>.

6. Select the project in this repo (only one project in this repo) then click Finish.

3.2 Generating, Building and Running the Example

1. In Project Explorer, right-click the project and select Update Code and Build Project. This will generate the configuration (Pins, Clocks, Peripherals), update the source code and build the project using the active configuration (e.g. Debug_FLASH). Make sure the build completes successfully and the *.elf file is generated without errors.

   

   Press Yes in the SDK Component Management pop-up window to continue.

2. Go to Debug and select Debug Configurations. There will be a debug configuration for this project:

   

    Configuration Name                  Description
    -------------------------------     -----------------------
    $(example)_debug_flash_pemicro      Debug the FLASH configuration using PEmicro probe
   

   Select the desired debug configuration and click on Debug. Now the perspective will change to the Debug Perspective. Use the controls to control the program flow.

4. Results

The servo motor follows the potentiometer position in real-time, simulating a steering control system. Upon startup, the servo centers to its neutral position. As the user rotates the potentiometer, the ADC reads the analog input and maps it to a corresponding PWM duty cycle, causing the servo to smoothly track the potentiometer angle. This demonstrates a basic steer-by-wire concept where driver input (potentiometer) is translated into actuator movement (servo).

5. Support

For general technical questions related to NXP microcontrollers, please use the NXP Community Forum.

Project Metadata

Questions regarding the content/correctness of this example can be entered as Issues within this GitHub repository.

Warning: For more general technical questions regarding NXP Microcontrollers and the difference in expected functionality, enter your questions on the NXP Community Forum

6. Release Notes

Version	Description / Update	Date
1.0	Initial release on Application Code Hub	May 22th 2026
1.1	Updated to FRDM Automotive S32K3 + S32M27 (RTD 7.0.1)	August 24th 2026