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ETAS Interfaces
A sender-receiver interface can be used to communicate data (using data element prototypes within the <DATA-ELEMENTS>
element) or modes (see section 6.2,
Mode
, on page 67 for more details).
Tip
In AUTOSAR R3.1.5 or lower , a sender-receiver interface can contain zero or more data elements and/or zero or more mode groups. However, it is good practice to separate interfaces used for data transfer and interfaces used for mode management.
In AUTOSAR R4.0.* , a sender-receiver interface must contain either data elements or a single mode group. If a sender-receiver interface contains both kinds of elements, an error is issued during code generation.
6.1.1
Data Element Prototypes
Each sender-receiver interface can specify zero or more data elements that constitute the
AUTOSAR signals communicated over the interface. Each data item defines a prototype of a specific type and can be a primitive data type, a RECORD or an ARRAY type. See chapter 4,
Data Types
, on page 33 for details of defining data types.
To create a data element in ASCET:
In the component manager, double-click on SRInterface .
The "Sender Receiver Interface Editor for: SRInterface" editor opens.
Use the Signed Discrete Variable button to create an sdisc variable.
The "Properties for Scalar Element: sdisc" dialog window opens.
Name the signed discrete variable Speed .
Figure 17 : Data element Speed for the sender-receiver interface SRInterface
To create an implementation of a data element:
In the "Sender Receiver Interface Editor for: SRInterface" editor, go to the Implementation tab.
In the Implementation tab, double-click the Speed element.
The "Implementation for: Speed" window opens.
In the "Master" field, activate Implementation .
In the "Implementation" field, select sint16 .
Right-click in the "Min" and "Max" fields and select Default
Value from the context menu.
Close the "Implementation for: sdisc" window with OK .
ASCET V6.3 AUTOSAR User’s Guide 64
ETAS Interfaces
The Implementation tab of the "Sender Receiver Interface
Editor for: SRInterface" editor shall look like the figure below.
Figure 18 : Implementation Impl of the sender-receiver interface SRInterface with data element Speed
An implementation of a sender-receiver interface in ASCET corresponds to a sender-receiver interface in AUTOSAR. The sender-receiver interface in configuration language is generated by ASCET in the file Swc_interfaces.arxml
.
In
AUTOSAR R3.1.5 or lower
, the declaration of data elements within a sender-receiver interface definition has the following structure:
Listing 27: ARXML code - declaration of data elements within sender-receiver interface
(AUTOSAR R3.1.2)
ASCET V6.3 AUTOSAR User’s Guide 65
ETAS Interfaces
In
AUTOSAR R4.0.*
, the declaration of data elements within a sender-receiver interface definition has the following structure:
Listing 28: ARXML code - declaration of data elements within sender-receiver interface
(AUTOSAR R4.0.2)
A data element is defined using the <DATA-ELEMENT-PROTOTYPE> 1 / <VARIABLE-DATA-
PROTOTYPE> 2 element, and all elements must be defined within an encapsulating <DATA-
ELEMENTS> element.
Each <DATA-ELEMENT-PROTOTYPE> / <VARIABLE-DATA-PROTOTYPE> element must specify:
the <SHORT-NAME> that you will use to refer to the item
the <SW-DATA-DEF-PROPS> data properties, among them
the <SW-CALIBRATION-ACESS>
a <TYPE-TREF> reference to the type of the data item
AUTOSAR R3.1.5 or lower only: whether the data reception <IS-QUEUED> or not
<IS-QUEUED>false</IS-QUEUED> – means that a newly received value overwrites the previous value of the datum. If a value is sent multiple times before it is received then the receiver can only access the last transmitted value.
1 AUTOSAR R3.1.5 or lower
2 AUTOSAR R4.0.*
ASCET V6.3 AUTOSAR User’s Guide 66
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