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Standard Servo Write

Set shaft position of standard servo motor to angle specified in degrees

  • Library:
  • Simulink Support Package for Arduino Hardware / Common


The Standard Servo Write block sets the shaft position of the servo motor from 0 to 180 degrees depending on the input value sent to the block on the Arduino® hardware pin.


If you use the Standard Servo Write block along with the Serial Receive and Serial Transmit blocks in a Simulink® model, use longer sample times to avoid overruns.

Maximum Number of Servo Blocks Allowed Per Simulink Model

The number of Servo blocks, Standard Servo Read, Standard Servo Write, and Continous Servo Write, you can use in your Simulink model depends on the number of timers on your Arduino hardware board. Every timer on the Arduino board can support up to 12 Servo blocks.

For example, consider the Arduino Mega 2560/ADK board. The maximum number of servo blocks that can be used per Simulink model is 48. If your Simulink model utilizes a total number of 48 Servo blocks and the board has 5 timers, timer 5 supports the first set of 12 (1 to 12) Servo blocks. Similarly, timer 1 supports the next set of 12 (13-24) Servo blocks, timer 3 supports the next set of 12 (25-36) Servo blocks, and finally, timer 4 supports the last set of 12 (37-48) servo blocks.

The Servo blocks are grouped as follows:

  • Set 1: Servo blocks 1 to 12

  • Set 2: Servo blocks 13 to 24

  • Set 3: Servo blocks 25 to 36

  • Set 4: Servo blocks 37 to 48

  • Set 5: Servo blocks 49 to 60

This table shows how to assign timers to Servo blocks depending on the Arduino board you are using. It also provides the maximum number of Servo blocks that you can use per Simulink model.

Arduino Board TypeTimerMaximum Number of Servo Blocks Per Simulink Model
Uno, Nano 3.01Set 1
Mega 2560/ADK1Set 2
3Set 3
4Set 4
5Set 1
Leonardo, Robot Control Board, Robot Motor Board, Micro1Set 1
MKR 1000, MKR Wifi 1010, MKR ZeroTC4Set 1
Nano 33 IoTTC4Set 1
DueTC3_CH0Set 1
TC4_CH1Set 2
TC5_CH2Set 3
TC2_CH2Set 4
TC0_CH0Set 5



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The value sent to the block at the input port determines the speed and direction of rotation of the standard rotation servo motor interfaced with the Arduino hardware board. For example:

  • Sending -90 to the block produces the maximum rate of rotation in one direction.

  • Sending 90 to the block produces the maximum rate of rotation in the opposite direction.

  • Sending 0 to the block stops the servo motor.

  • Sending out-of-range values, such as -95 or 300, to the block has the same effect as sending the minimum or maximum input values, respectively.

The block input port inherits the data type of the upstream block, and internally converts it to uint8 with an offset of 90.

Data Types: uint8


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Specify the Arduino hardware board pin number to which the standard rotation servo write motor input signal is connected.


Do not assign the same pin number to multiple blocks within a Simulink model.

For more information on how to assign pins or view the pins for the Standard Servo Write block, see Pin Mapping for Arduino Timer Dependent Blocks.

Click this button to view the pin mapping table associated with the Arduino hardware board you select.

Introduced in R2012a