Summary of Interfacing Servo Motor with PIC Microcontroller – MPLAB XC8
A servo motor is a geared DC motor with a closed-loop mechanism for precise angular control, typically used in robotics. It operates within fixed rotation limits (usually 90° to 180°) and requires three wires: power (red/black) and a PWM control signal (various colors). Unlike standard DC motors, reversing polarity damages the circuit. This project demonstrates interfacing a VIGOR VS-10A servo with a PIC 16F877A microcontroller using MPLAB XC8, utilizing pulse widths between 800μS and 2200μS at 4.8V to 6V.
Parts used in the Interfacing Servo Motor with PIC Microcontroller:
- Servo Motor
- PIC 16F877A Microcontroller
- VIGOR VS-10A Servo Motor
- MPLAB XC8 Compiler
Servo Motor is an ordinary geared dc motor equipped with closed loop servo mechanism which uses position feedback to control exact angular position of the rotor. These are commonly used in robotic arms, legs etc. Servo Motors do not rotate continuously, their rotation is limited to fixed angles. Usually these motors have rotation limit from 90º to 180° and some special have limits 360° or more.
Servo Motors usually have three wires. RED and BLACK wires are used to provide power. Required voltage will depend upon the type of servo you are using, so please refer the specifications given by the manufacture. The third wire is used to provide control signals to control exact angular position of the servo motor. Its color varies for different manufactures such as YELLOW, BROWN, WHITE etc.
Servo Motor shaft can be moved to desired position by using Pulse Width Modulated (PWM) signals on the control wire.
Unlike DC Motors, reversing the power supply polarity does not reverse the rotation instead of it may damage the control circuitry.
Servo Motors can be easily interfaced with PIC Microcontroller. Here for demonstration we are using PIC 16F877A and VIGOR VS-10A servo motor. The required pulse width of this servo motor ranges from 800μS to 2200μS and rotation angle is greater than or equal to 170°. Its operating voltage range is 4.8V to 6V.
Circuit Diagram
For more detail: Interfacing Servo Motor with PIC Microcontroller – MPLAB XC8
- What is a servo motor?
An ordinary geared DC motor equipped with a closed loop servo mechanism that uses position feedback to control exact angular position. - How many wires does a servo motor usually have?
Servo motors usually have three wires for power and control signals. - Can servo motors rotate continuously?
No, servo motors do not rotate continuously; their rotation is limited to fixed angles. - What happens if you reverse the power supply polarity on a servo motor?
Reversing the power supply polarity does not reverse rotation and may damage the control circuitry. - Which microcontroller was used for demonstration in this project?
The PIC 16F877A microcontroller was used for the demonstration. - What is the required pulse width range for the VIGOR VS-10A servo motor?
The required pulse width ranges from 800μS to 2200μS. - Does the color of the control wire vary?
Yes, the third wire color varies for different manufacturers such as yellow, brown, or white. - What software tool is mentioned for this project?
MPLAB XC8 is the tool mentioned for interfacing the servo motor.
