Bus Creator
Create bus from input elements
- Library:
Simulink / Commonly Used Blocks
Simulink / Signal Routing
HDL Coder / Signal Routing
Description
The Bus Creator block combines a set of input elements into a bus. You can connect any element types to the input ports, including other buses. You can access elements in a bus by using a Bus Selector block.
Elements of a bus must have unique names. By default, each element of the bus inherits
the name of the element connected to the Bus Creator block. If duplicate
names are present, the Bus Creator block appends the port number to all
input element names. For elements that do not have names, the Bus Creator
block generates names in the form signaln, where n
is the port number connected to the element. You can refer to elements by name when you
search for their sources or select elements for connection to other blocks. For element
naming guidelines, see Signal Names and Labels.
Ports
Input
Output
Parameters
Number of inputs — Number of input elements
2 (default) | integer
Number of input elements, not fewer than two, specified as an integer. Increasing the number of inputs adds empty input ports to the block. Before you simulate the model, make sure that an input element is connected to each input port.
When you modify the Number of inputs parameter, click Refresh to update the list of elements.
Tip
If all input ports are already connected, you can add an input port to the Bus Creator block by connecting another line to it.
Interactively adding a port updates the Number of inputs parameter and adds the new element to the list of elements in the bus.
Programmatic Use
Block Parameter:
Inputs |
| Type: character vector |
| Values: integer greater than or equal to 2, comma-separated list of element names |
Default:
'2' |
By default, the Inputs parameter specifies the
number of inputs. When you use it to specify the names of elements in
the bus, the number of inputs matches the number of element names you
specify.
Elements in the bus — List of input elements
list of element names
List of input elements to combine into a bus. You can view all elements entering the block, including the elements contained in nested buses. An arrow next to a element indicates that an input element is a bus. To display the contents of that bus, click the arrow.
To rearrange the elements in the output bus, use the Up and Down buttons. You can select multiple top-level adjacent elements in the Elements in the bus list to reorder or remove.
To find the source of any element entering the block, select the element in the Elements in the bus list and click the Find button. Simulink® highlights the icon of the source, opening the subsystem that contains the element source, if necessary.
If you change an element name while the Block Parameters dialog box is open, you can see the updated name by clicking Refresh.
Programmatic Use
Block Parameter:
Inputs |
| Type: character vector |
| Values: integer greater than or equal to 2, comma-separated list of element names |
Default:
'2' |
By default, the Inputs parameter specifies the
number of inputs. When you use it to specify the names of elements in
the bus, the number of inputs matches the number of element names you
specify.
Filter by name — Search term for filtering displayed input elements
text
Search term for filtering displayed input elements, specified as text. Do not enclose the search term in quotation marks. The filter does a partial string search.
To access the filtering options, click the Show filtering
options
button to the right of the Filter by
name box.
Enable regular expression — Option to filter displayed input elements by regular expression
off (default) | on
Option to filter the displayed input elements by regular expression.
When this parameter is enabled, entering t$ in the
Filter by name box displays all elements whose
names end with a lowercase t (and their immediate
parents). For details, see Regular Expressions.
Dependencies
To access this parameter, click the Show filtering
options
button to the right of the Filter by
name box.
Show filtered results as a flat list — Option to display filtered results as a flat list
off (default) | on
Option to display filtered results as a flat list that uses dot notation to reflect the hierarchy of buses. By default, the filtered elements appear in a hierarchical tree.
Dependencies
To access this parameter, click the Show filtering
options
button to the right of the Filter by
name box.
Output data type — Data type of output bus
'Inherit: auto' (default) | 'Bus: <object name>' | <data type expression>
Data type of the output bus.
If you select Bus: <object name>, replace
<object name> with the name of a Simulink.Bus object. The
Bus object must be accessible when you edit the
model.
To define a Bus object using the Bus
Editor, click the Show data type assistant
button 
, and then click the
Edit button.
If you select <data type expression>,
specify an expression that evaluates to a Bus
object.
Programmatic Use
Block Parameter:
OutDataTypeStr |
| Type: character vector |
Values:
'Inherit: auto' | 'Bus: <object
name>' |
Default:
'Inherit: auto' |
Require names of inputs to match names above — Check that input element names match names listed in dialog box
off (default) | on
Check that the input element names match the names listed in the Block Parameters dialog box. If the element names do not match, Simulink returns an error.
Tips
The Require names of inputs to match names above parameter might be removed in a future release. To enforce strong data typing, consider using the Use names from inputs instead of from bus object parameter.
Dependencies
If you select Use names from inputs instead of from bus object, the Simulink software ignores the Require names of inputs to match names above setting.
If you change the Number of inputs
programmatically, this parameter reverts to
'off'.
Rename selected signal — New name for selected input element
'' (default) | character vector
New name for the selected input element. See Signal Names and Labels for name guidelines.
Dependencies
To display this parameter, enable the Require names of inputs to match names above parameter.
Use names from inputs instead of from bus object — Option to use names from input elements instead of from Simulink.Bus object
on (default) | off
By default, the Bus Creator block uses the input element
names as the output bus element names, even when you specify a
Simulink.Bus object as the data type.
To inherit bus element names from the Bus object, clear
this parameter. Clearing the parameter:
Enforces strong data typing.
Avoids having to enter an element name multiple times: in the
Busobject and in the model. Entering the name multiple times can accidentally create element name mismatches.Supports the array of buses requirement to have consistent element names across array elements.
Alternatively, you can enforce strong data typing by checking that input
element names match the Bus object element names. Keep the
Use names from inputs instead of from bus object
check box selected and set the Element name
mismatch configuration parameter to
error.
Dependencies
To display this parameter, set the Output data
type parameter to a Bus object.
Programmatic Use
Block Parameter:
InheritFromInputs |
| Type: character vector |
Values:
'on' | 'off' |
Default:
'on' |
Output as nonvirtual bus — Output nonvirtual bus
off (default) | on
Output a nonvirtual bus instead of a virtual bus.
All elements in a nonvirtual bus must have the same sample time, even if
the elements of the associated Bus object specify inherited
sample times for some elements. Any operation resulting in a nonvirtual bus
containing elements with different sample rates generates an error. To
change the sample time of an element or bus that has a different sample time
than the other nonvirtual bus input elements, use a Rate Transition block. For
details, see Modify Sample Times for Nonvirtual Buses.
To generate code that uses a C structure to define the structure of the bus that this block creates, enable this parameter.
Dependencies
To display this parameter, set the Output data
type parameter to a Bus object.
Programmatic Use
Block Parameter:
NonVirtualBus |
| Type: character vector |
Values:
'on' | 'off' |
Default:
'off' |
Model Examples
Block Characteristics
Data Types |
|
Direct Feedthrough |
|
Multidimensional Signals |
|
Variable-Size Signals |
|
Zero-Crossing Detection |
|
Tips
For buses at subsystem and model interfaces, you can use Out Bus Element blocks instead of a Bus Creator block with an Outport block. Out Bus Element blocks:
Reduce line complexity and clutter in a block diagram.
Make it easier to change the interface incrementally.
Extended Capabilities
See Also
Bus Assignment | Bus Selector | Bus to Vector | Out Bus Element