Servo Motor

Represent connected servo motor and set angular position value

• Library:

• Simulink Coder Support Package for ARM Cortex-based Microcontroller / Actuators

• 

Description

The Servo Motor block reprsents a servo motor connected to a specified motor channel on an ARM^® Cortex^®-based VEX^® Microcontroller. The input signal sets the angular position value of the servo motor. There are 10 motor channels, or pins, on the VEX microcontroller that you can connect to servo motors. For information on the pin layout of the microcontroller, see the VEX Cortex Pin-Out diagram from VEX Robotics.

Ports

Input

Port_1 — Input signal that sets angular position of servo motor

integer in [ –128 127]

The input signal for the Servo Motor block can be derived from other blocks in the model. For example:

• If a Gamepad Joystick block is connected as the input for a Servo Motor block, the input value can range from –128 to 127 based on the position of the joystick, which then translates to an angular position value (in degrees) of the servo. For block input value ‘0’, the servo motor is stationary.

• If a Gamepad Button block along with a Gain block is connected as the input for a Servo Motor block, the input can be set to a particular value for the duration for which the button is kept pressed, which translates to an angular position value (in degrees) of the servo.

During simulations without the hardware, the Servo Motor block emits zeroes if there is no block connected to the input port (see Block Produces Zeros or Does Nothing in Simulation). If the input value to the Servo Motor is beyond the range of –128 to 127, you receive an error message during simulation.

Data Types: double

Output

Port_1 — Servo angle during simulation

scalar

The output is the angle, in degrees, of the servo motor. Connect a Sink block, such as a Display or Scope block, to the output port to view the simulation output. The Sink blocks are available in the Utilities library in Simulink^® Support Package for ARM Cortex-based VEX Microcontroller.

Dependencies

This port appears only when you select the Add output port to measure the servo angle during simulation parameter.

Data Types: double

Parameters

Motor Channel — Select motor channel for servo motor

1 (default) | 1 to 10

Select the motor channel or pin on the ARM Cortex-based VEX Microcontroller that is connected to the servo motor.

Do not assign the same channel number to more than one Servo Motor block within the same model.

Add output port to measure the servo angle during simulation — Add output port for simulation

off (default) | on

Select this check box to add the output port to emit the angle of the servo motor during simulation.

Model Examples

Servo Control using a Gamepad Button

Use Simulink Coder Support Package for ARM Cortex-based VEX Microcontroller to control a servo motor using a digital button on the VEXnet Joystick.

Extended Capabilities

C/C++ Code Generation

Generate C and C++ code using Simulink® Coder™.

During code generation, any simulation block that is connected to the output port of a Servo Motor block is ignored and has no effect on the generated code.