Servo Output

Write to standard servo output channels

• Library:

• Simulink Desktop Real-Time

• 

Description

Set the shaft position of a standard servo motor.

To rotate the servo shaft, send values to the block input.

Sending out-of-range values to the block input has the same effect as sending the minimum or maximum input values.

The block input inherits the data type of the upstream block.

Ports

Input

Servo Data — Servo data to write to output channels

double | single | int8 | uint8 | int16 | uint16 | int32 | uint32 | boolean

Servo position (angle). The minimum and maximum values for shaft position vary with the Block input signal (units) argument value:

Block input signal	Minimum Servo Data	Maximum Servo Data
Degrees (default)	0	180
Radians	0	pi
Normalized bipolar	-1	1
Normalized unipolar	0	1

Example: 90

Data Types: double | single | int8 | uint8 | int16 | uint16 | int32 | uint32

Output

Missed Ticks — Missed tick count (optional)

double

In normal or accelerator modes, returns the number of timer ticks that your model lags behind the real-time kernel. When the model lags by more than Maximum missed ticks, the software reports an error and simulation stops.

Dependency

When you select Show “Missed Ticks” port, this port is visible.

Data Types: double

Parameters

Install new board — Register a board

< no board selected > (default)

When you click Install new board, the software displays a list of manufacturers of supported boards. When you select a manufacturer, the software displays a list of boards available from that manufacturer. When you select a board, the software adds the board to the list of registered boards and makes that board the current board.

By default, the initial selection in the list of registered boards is < no board selected >.

Dependency

When you select a board in the list of registered boards, the Delete current board and Board setup buttons are available.

Delete current board — Delete the current board

(button)

To delete the current board, click this button. The initial selection of the list of registered boards changes to < no board selected >.

Dependency

To activate this parameter, select a board in the list of registered boards.

When you delete the current board, the Delete current board and Board setup buttons are no longer available.

Board setup — Set up the board

(button)

To set up the board, click this button.

A board-specific dialog box opens to set up the board. For more information, see the board manufacturer documentation.

Dependency

To activate this parameter, select a board in the list of registered boards.

To deactivate this parameter, click Delete current board.

Sample time — Sample time of block

0.1 (default) | double

Enter a value, in seconds, that represents how frequently you want the block to execute and interact with the I/O hardware. The block synchronizes your model with the real-time clock at this sample rate.

If you are using a fixed-step solver, enter the value that you entered as the Fixed step size configuration parameter or an integer multiple of that value.

Maximum missed ticks — Number of timer ticks by which your model can trail the kernel

10 (default) | integer

In normal or accelerator modes, enter the number of timer ticks that your model can lag behind the real-time kernel. When the model lags behind by this number or fewer timer ticks, the software assumes that the lag is temporary. It allows the model to catch up, even if the model misses some ticks. When the model lags by more than this number, the software reports an error and simulation stops.

In external mode, the software ignores this value.

Show “Missed Ticks” port — Send number of missed ticks to port Missed Ticks

'off' (default) | 'on'

In normal or accelerator modes, select this check box to send the number of missed ticks to output port Missed Ticks.

In external mode, the Missed Ticks port is zero.

Yield CPU when waiting — Yield CPU while kernel waits for hardware

'off' (default) | 'on'

In normal or accelerator modes, select this check box to grant other programs more CPU time while the kernel waits for a response from the hardware.

In external mode, the software ignores this value.

Output channels — Channel vector that selects other output channels

1 (default) | vector

Enter a channel vector that selects the other output channels that you are using on this board. The vector can be any valid MATLAB^® vector form. For example, to select the first two other output channels, enter:

[1,2]

or

[1:2]

Block input signal — Units of the block input signal

Degrees (default) | Radians | Normalized bipolar | Normalized unipolar

Select the units of the block input signal that specifies servo position.

Minimum pulse duration — Duration of the control pulse

500e-6 (default)

Select the duration of the control pulse that corresponds to the minimum servo angle. Because not all servos are the same, this parameter lets you calibrate the input signal to the actual servo angle.

Maximum pulse duration — Duration of the control pulse

2500e-6 (default)

Select the duration of the control pulse that corresponds to the maximum servo angle. Because not all servos are the same, this parameter lets you calibrate the input signal to the actual servo angle.

Initial value — Specify the value that the channel generates before execution starts

vector

Enter the initial value for each output channel that you entered in the Output channels box.

Final value — Specify the value that the channel generates after execution ends

vector

Enter the final value for each output channel that you entered in the Output channels box.