Out Bus Element, Bus Element Out

Specify output that connects to external port

• Library:

• Simulink / Ports & Subsystems

  Simulink / Sinks

  HDL Coder / Ports & Subsystems

  HDL Coder / Sinks

• 

Description

The Out Bus Element block, also known as the Bus Element Out block, combines the functionality of an Outport block and a Bus Creator block. This block is of the Outport block type and all Out Bus Element blocks that use the same port share a dialog box.

The output of an Out Bus Element is a bus, regardless of the number and type of signals connected to it. You must connect an Out Bus Element block to each signal that you want the bus to contain.

Create Port and Related Blocks

When you insert an Out Bus Element block, the block label populates with default values. The label consists of two interactive text fields: the port name and the bus element. To change the name of the port associated with the block, edit the first text field in the label by clicking the text.

To output multiple signals in a bus, create one Out Bus Element block for each signal that you want to include in the bus. In the Block Parameters dialog box, you can select the Add a new signal or Add a new sub-bus buttons. Alternatively, hold Ctrl while you drag an existing Out Bus Element block to a new location. Upon releasing the mouse, click Use Existing Port.

If multiple blocks are associated with the same port and you change the name of the port, all blocks that share the port update to reflect the new port name.

To create a port, hold Ctrl while you drag an existing Out Bus Element block to a new location. Upon releasing the mouse, click Create New Port.

Modify Port Output

In the Block Parameters dialog box, you can:

• Change port and element names.

• Reorder bus elements by dragging and dropping an element in the list of elements.

• Remove blocks associated with selected elements by clicking the Remove blocks of selected signals button .

Specify Element Name

To change the name of the bus element associated with the block, edit the second text field in the label by clicking the text.

Tip

To pass the block input to the external output port without nesting it in a bus, delete the text from the second text field in the label.

All element names associated with the port must be unique. You cannot specify the same element name more than once for a port. Simulink^® does not support overlapping writes to the same port.

To create hierarchy in the output bus, use dots in the part of the label that describes the bus element. Each dot indicates a new level of bus hierarchy.

To reduce the size of the label, you can display only the element name by selecting the block, pausing on the ellipsis, and selecting Compact Notation from the action bar. To show the bus hierarchy again, select Expanded Notation from the action bar.

Log Output Data

When you save output data to the workspace or a file, bus data defined by groups of root-level Out Bus Element blocks are logged along with root-level Outport block data.

Ports

Input

Port_1 — Full or partial output for external port

signal | message

Full or partial output that is associated with an external subsystem or model port.

• When multiple Out Bus Element blocks are associated with the same external port, the input to this block is an element of the bus at the output port. The second text field in the label specifies the element name.

• When one Out Bus Element block is associated with the external port, the input to this block is passed directly to the output port or nested in a bus at the output port. To pass the input of the block to the output port without nesting it in a bus, delete the text from the second text field in the label.

Data Types: single | double | half | int8 | int16 | int32 | int64 | uint8 | uint16 | uint32 | uint64 | string | Boolean | fixed point | enumerated | bus

Parameters

Port name — Name of output port

OutBus (default) | port name

Specify a port name that is not already in use by another block or port. The name appears on the parent Subsystem or Model block. The name also appears next to the block. Multiple blocks can access the same port.

Programmatic Use

Block Parameter: PortName

Type: character vector

Values: 'OutBus' | '<port name>'

Default: 'OutBus'

Port number — Position of port on parent block

1 (default) | real integer

Specify the order in which the port that corresponds to the block appears on the parent Subsystem or Model block.

• If you add a block that creates another port, the port number is the next available number.

• Deleting all blocks associated with a port deletes the port. Other ports are renumbered so that they are sequential and do not skip any numbers.

• Specifying a port number that exceeds the number of ports creates a port for that number and for any skipped sequential numbers.

Programmatic Use

Block Parameter: Port

Type: character vector

Values: real integer

Default: '1'

Set color — Specify block background color

Black (default) | White | Red | Green | Blue | Cyan | Magenta | Yellow | Gray | Light Blue | Orange | Dark Green | More Colors

Specify the block background color. This specification sets the color of blocks associated with selected bus elements, or of all blocks associated with the port if you do not select any bus elements.

Programmatic Use

Block Parameter: BackgroundColor

Type: character vector

Values: 'black' | 'white | 'red' | 'green' | 'blue' | 'cyan' | 'magenta' | 'yellow' | 'gray' | 'lightBlue' | 'orange' | 'darkGreen' | '[r,g,b]' where r, g, and b, are the red, green, blue values of the color in the range 0.0 to 1.0

Default: 'black'

Filter — Filter set of displayed signals

text

Specify a search term to use for filtering a long list of bus elements. Do not enclose the search term in quotation marks. The filter does a partial string search and supports regular expressions. To use a regular expression character as a literal, include an escape character (\). For example, to use a question mark, type sig\?1.

Attributes

To specify attributes, click the pencil button or nondefault attribute summary next to the name of a bus or bus element.

Data type — Data type

Inherit: auto (default) | double | single | half | int8 | uint8 | int16 | uint16 | ...

The data type can be inherited, specified directly, or expressed as a data type object such as a Simulink.NumericType object.

You can specify any of these options:

• Inherited data type

• Built-in Simulink data type — For example, specify single or uint8. See Data Types Supported by Simulink.

• Fixed-point data type — Use the fixdt function. For example, specify fixdt(1,16,0).

• Enumerated data type — Use the name of the type preceded by Enum:. For example, specify Enum: myEnumType.

• Bus data type — Use the name of the Simulink.Bus object preceded by Bus:. For example, specify Bus: myBusObject.

• Value type — Use the name of the Simulink.ValueType object preceded by ValueType:. For example, specify ValueType: windVelocity.

• Custom data type — Use a MATLAB^® expression that specifies the type. For example, you can specify a Simulink.NumericType object whose DataTypeMode property is set to a value other than 'Fixed-point: unspecified scaling'.

When you specify a Simulink.ValueType or Simulink.Bus object, the object defines more than the data type. The object also defines properties such as Min, Max, and Unit. The property values specified by the ValueType object override the corresponding property values specified by a block. For example, suppose a block sets Unit to ft/s. When the Data type of the block specifies a ValueType object that has m/s as its unit, the block uses m/s instead of ft/s.

Programmatic Use

Block Parameter: OutDataTypeStr

Type: character vector

Values: 'Inherit: auto' | 'double' | 'single' | 'half' | 'int8' | 'uint8' | 'int16' | 'uint16' | 'int32' | 'uint32' | 'int64' | 'uint64' | 'boolean' | 'fixdt(1,16)' | 'fixdt(1,16,0)' | 'fixdt(1,16,2^0,0)' | 'string' | 'Enum: <class name>' | 'Bus: <object name>' | 'ValueType: <object name>' | '<data type expression>'

Default: 'Inherit: auto'

Data mode — Data mode of bus elements

inherit (default) | signal | message

Specify the data mode of the elements of the bus.

• inherit — Bus elements inherit their data modes.

• signal — Bus elements must be signals.

• message — Bus elements must be messages.

  For the In Bus Element block, if you choose message as the data mode, an envelope button appears next to the bus or bus element. Use the envelope button to specify custom queue properties for each message element. The Out Bus Element block does not support queue specifications.

Dependencies

To enable this parameter, the block must be at the top level of a model.

Programmatic Use

Block Parameter: DataMode

Type: character vector

Values: 'inherit' | 'signal' | 'message'

Default: 'inherit'

Bus virtuality — Virtual or nonvirtual bus

inherit (default) | virtual | nonvirtual

Specify whether to inherit the bus virtuality or define the bus as virtual or nonvirtual. For more information, see Types of Composite Signals.

This parameter determines whether the blocks inherit or define the bus virtuality. If the blocks define the bus virtuality and the virtuality of the input bus does not match, compiling the model produces an error.

Dependencies

To enable this parameter, set Data type to a Bus object.

Programmatic Use

Block Parameter: BusVirtuality

Type: character vector

Values: 'inherit' | 'virtual' | 'nonvirtual'

Default: 'inherit'

Dimensions — Signal dimensions

-1 (default) | integer | [integer, integer]

Specify the dimensions of a signal.

• -1 — The signal can have any dimensions.

• N — The signal must be a vector of size N.

• [R C] — The signal must be a matrix having R rows and C columns.

Programmatic Use

Block Parameter: PortDimensions

Type: character vector

Values: '-1' | integer | [integer, integer]

Default: '-1'

Dims mode — Option to allow only variable-size or fixed-size signals

Inherit (default) | Fixed | Variable

Specify the type of signals allowed.

• Inherit — Allow variable-size and fixed-size signals.

• Variable — Allow only variable-size signals.

• Fixed — Allow only fixed-size signals. Do not allow variable-size signals.

When the signal is variable-sized, the Dimensions parameter specifies the maximum dimensions of the signal.

Programmatic Use

Parameter: VarSizeSig

Type: character vector

Value: 'Inherit' | 'No' | 'Yes'

Default: 'Inherit'

Unit — Physical unit

inherit (default) | <Enter unit>

Specify the physical unit of the signal. For a list of supported units, see Allowed Unit Systems.

Programmatic Use

Block Parameter: Unit

Type: character vector

Values: 'inherit' | '<Enter unit>'

Default: 'inherit'

Sample time — Sample time

-1 (default) | scalar

Specify the discrete interval between sample time hits or specify another appropriate sample time such as continuous or inherited.

By default, the signal inherits its sample time. To set a different sample time, enter a valid sample time based on the table in Types of Sample Time.

Programmatic Use

Block Parameter: SampleTime

Type: character vector

Values: scalar

Default: '-1'

Complexity — Numeric type

auto (default) | real | complex

Specify the numeric type of the signal. To choose the numeric type of the signal, select auto. Otherwise, choose a real or complex signal type.

Programmatic Use

Block Parameter: SignalType

Type: character vector

Values: 'auto' | 'real' | 'complex'

Default: 'auto'

Minimum — Minimum value

[] (default) | scalar

Lower value of the range that Simulink checks.

This number must be a finite real double scalar value.

Simulink software uses this value to perform:

• Simulation range checking (see Specify Signal Ranges).

• Automatic scaling of fixed-point data types.

• Optimization of the code that you generate from the model. This optimization can remove algorithmic code and affect the results of some simulation modes such as SIL or external mode. For more information, see Optimize using the specified minimum and maximum values (Embedded Coder).

Programmatic Use

Block Parameter: OutMin

Type: character vector

Values: '[]' | scalar

Default: '[]'

Maximum — Maximum value

[] (default) | scalar

Upper value of the range that Simulink checks.

This number must be a finite real double scalar value.

Simulink software uses this value to perform:

• Simulation range checking (see Specify Signal Ranges).

• Automatic scaling of fixed-point data types.

• Optimization of the code that you generate from the model. This optimization can remove algorithmic code and affect the results of some simulation modes such as SIL or external mode. For more information, see Optimize using the specified minimum and maximum values (Embedded Coder).

Programmatic Use

Block Parameter: OutMax

Type: character vector

Values: '[]' | scalar

Default: '[]'

Description — Description of bus or bus elements

no default

Use the description to document information about the bus or bus element, such as where it is used. This information does not affect Simulink processing.

Programmatic Use

Block Parameter: Description

Type: character vector

Values: '' | '<Enter text>'

Default: ''

Model Examples

Connect Multiple Output Signals to a Port

Group the output signals of a subsystem or model into a virtual bus using Out Bus Element blocks.

Simplify Bus Interfaces in Subsystems and Models

Convert a subsystem or model interface that uses Inport, Bus Selector, Bus Creator, and Outport blocks to use In Bus Element and Out Bus Element blocks.

Combine Multiple Subsystem Ports into One Port

Three ways to simplify a subsystem interface by converting multiple ports and their connected signals into one port and a bus. Model interfaces do not support this automated conversion.

Block Characteristics

Data Types	Boolean | bus | double | enumerated | fixed point | half | integer | single | string
Direct Feedthrough	no
Multidimensional Signals	yes
Variable-Size Signals	yes
Zero-Crossing Detection	no

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

HDL Code Generation

Generate Verilog and VHDL code for FPGA and ASIC designs using HDL Coder™.

This block can be used to simplify the Subsystem bus interfaces when you use the block in subsystems that generate HDL code, but is not included in the hardware implementation.

To learn more about using buses for HDL code generation, see Buses (HDL Coder) and Use Bus Signals to Improve Readability of Model and Generate HDL Code (HDL Coder).

Fixed-Point Conversion
Design and simulate fixed-point systems using Fixed-Point Designer™.