FlexRay Fibex Support Service

Table of Contents

• Working with the FlexRay Stream Type
• Low level FlexRay data handling
• Fibex database access
• High level signal handling

Note

Using this service will automatic load the adtffileplugin for deserialization and extend the support for recordings containg data from ADTF Device Toolbox 2.x, there is no need to add the devtb2 support service as well. See ADTF Device Toolbox 2.x Support.

Plugin Information

Plugin Filename	flexray.adtfplugin
Plugin Description	flexray.plugindescription
Plugin Name	FlexRay Fibex Support Service Plugin
License	ADTF
Support Mail	support@digitalwerk.net
Homepage URL	www.digitalwerk.net

Plugin Versions

Plugin Version	3.12.1
Plugin File Version	1.0
adtf::devicetb	3.12.1
adtf	3.18.3
adtf::ucom	3.1.0

Component Information

Name	FlexRay Fibex Support Service
CID	flexray.service.devicetb.cid
Description	Use this service to extend the ADTF System with FlexRay support using fibex database.
Type	Service
Default Runlevel	session

Properties

Name	Value	Type	Description	Subproperties
flexray_channel_1		cFilenameList	Database for mapped FlexRay channel 1
flexray_channel_1_cluster_name		cString	Cluster name for mapped FlexRay channel 1
flexray_channel_2		cFilenameList	Database for mapped FlexRay channel 2
flexray_channel_2_cluster_name		cString	Cluster name for mapped FlexRay channel 2
flexray_channel_3		cFilenameList	Database for mapped FlexRay channel 3
flexray_channel_3_cluster_name		cString	Cluster name for mapped FlexRay channel 3
flexray_channel_4		cFilenameList	Database for mapped FlexRay channel 4
flexray_channel_4_cluster_name		cString	Cluster name for mapped FlexRay channel 4
flexray_channel_5		cFilenameList	Database for mapped FlexRay channel 5
flexray_channel_5_cluster_name		cString	Cluster name for mapped FlexRay channel 5
flexray_channel_6		cFilenameList	Database for mapped FlexRay channel 6
flexray_channel_6_cluster_name		cString	Cluster name for mapped FlexRay channel 6
flexray_channel_7		cFilenameList	Database for mapped FlexRay channel 7
flexray_channel_7_cluster_name		cString	Cluster name for mapped FlexRay channel 7
flexray_channel_8		cFilenameList	Database for mapped FlexRay channel 8
flexray_channel_8_cluster_name		cString	Cluster name for mapped FlexRay channel 8
flexray_channel_9		cFilenameList	Database for mapped FlexRay channel 9
flexray_channel_9_cluster_name		cString	Cluster name for mapped FlexRay channel 9
updatebit_behavior	0	tInt32	If the PDU update-bits check is disabled (set to false), set this property how a PDU update is handled. For more information see chapter "FlexRay Service" in the SDK documentation.
use_legacy_updatebits	false	tBool	Check the update-bits in the PDU.

Required Interfaces

IID
flexray_xml.parser.flexray.sdk.devicetb.adtf.iid
macroresolver.ant.base.adtf.iid
adtf_file_objects.devil.services.adtf.iid

Provided Interfaces

IID
bus_database_registry.axle.sdk.devicetb.adtf.iid
flexray.axle.flexray.sdk.devicetb.adtf.iid
flexray_database.axle.flexray.sdk.devicetb.adtf.iid
flexray_coder.axle.flexray.sdk.devicetb.adtf.iid

Working with the FlexRay Stream Type

The Pins for receiving or sending new FlexRay Samples must be from a FlexRay Stream Type. The following code shows how to create an Output Pin with this type:

adtf::streaming::ISampleWriter* m_pWriter = CreateOutputPin("flexray_output", adtf::devicetb::sdk::flexray::stream_meta_type_flexray());
adtf::streaming::ISampleReader* m_pReader = CreateInputPin("flexray_input", adtf::devicetb::sdk::flexray::stream_meta_type_flexray());

All samples which are transmitted on these pins are assumed to be from a FlexRay Stream Type.

Low level FlexRay data handling

FlexRay data is stored in specific ADTF media samples of the type adtf::devicetb::sdk::flexray::stream_meta_type_flexray. The data structure used to store FlexRay frames is adtf::devicetb::sdk::flexray::tFlexRayData. Inside the media sample a vector of this frames is stored, which can be easily accessed by using the class adtf::devicetb::sdk::flexray::cFlexRayFrameVector. The following example shows the handling of a FlexRay media samples like it may be implemented by the OnPinEvent method of an ADTF filter:

tResult cMyFlexRayFilter::ProcessInput(adtf::base::tNanoSeconds /*tmTrigger*/,
            adtf::streaming::ISampleReader* pReader)
{
    object_ptr<const ISample> pReadSample;
    if(IS_OK(pReader->GetNextSample(pReadSample))
    {
        object_ptr_shared_locked<const ISampleBuffer> oSampleBuffer;
 
        RETURN_IF_FAILED(pReadSample->Lock(oSampleBuffer));
        if(oSampleBuffer)
        {
            adtf::devicetb::sdk::flexray::cFlexRayFrameVector oFrameVector(oSampleBuffer->GetPtr(), oSampleBuffer->GetSize());
            
            for (cFlexRayFrameVector::cIterator it = oFrameVector.GetFirst(); it.IsValid(); ++it)
            {
                const tFlexRayData* pData =it;
                switch (pData->nTag)
                {
                case tFlexRayData::FR_TAG_PDU:
                {
                    ...
                }
                case tFlexRayData::FR_TAG_FRAME:
                {
                    ...
                }
                default:
                    break;
                }
            }
        }
        
        oSampleBuffer->Unlock();
    }
 
    RETURN_NOERROR;
}

An example for creating flexray data is provided within the flexray-randomgenerator-example.

Fibex database access

The configuration of the FlexRay communication parameters and scheduling is stored in the Fibex database. To access this database the flexray service should be used. This service implements the adtf::devicetb::sdk::flexray::IFlexRaySupport interface. The corresponding nChannelID handles the requested property variable (further information here: subsection_flx_channel_properties). To get access to this database the following code sequence can be used:

// Query FlexRay service object
object_ptr<adtf::devicetb::sdk::flexray::IFlexRaySupport> poFlexRayService;
RETURN_IF_FAILED(_runtime->GetObject(poFlexRayService));
 
object_ptr<adtf::devicetb::sdk::flexray::IFlexRayDatabase> poFIBEXDatabase;
RETURN_IF_FAILED(poFlexRayService->GetDatabase(nChannelId, poFIBEXDatabase)));

ADTF provides the possibility to load Fibex Files via the flexray service. If you enter a Fibex file here, it will be parsed and loaded into the cache after playing your configuration.

Note

If you play a configuration, the Fibex file (as specified in the property "flexray_channel") will be parsed and loaded into the cache. If the Fibex file has changed during your ADTF session, it will be parsed and loaded again (If you play your configuration after the file has changed!). The old version of this file will then be removed from the cache. If you change the value of "flexray_channel" to another Fibex file and play the configuration again, this Fibex file will also be loaded into the cache. This is because ADTF checks the filename and alteration date of the given Fibex file. Please keep in mind that your sytem memory can increase significantly, if you repeat this many times!

High level signal handling

To handle signal values on a high level abstraction the FlexRay coder objects can be used. Objects of this type can be created by the FlexRay service. They implement the interface adtf::devicetb::sdk::flexray::IFlexRayCoder. Signals and PDUs are identified by IDs. These IDs are assigned by the FlexRay service during runtime. They can be used during the lifetime of filter modules.

Note

The value of IDs may change on the next start of the configuration. IDs should not be stored in the DAT file.

The decoding of signal values can be achieved on two different ways:

• By calling the method adtf::devicetb::sdk::flexray::IFlexRayCoder::GetSignalValue
  If valid data exists in the internal buffer of the coder object the actual value of the specified signal is returned.

Note

It is recommended to use different instances of a FlexRay coder for transmitting and receiving events. Otherwise setting a signal for transmission might interfere with getting a signal in a concurrently performed receive operation.

Both ways are influenced by the property flexray_updatebit_behavior. According to the settings of this property, PDUs and signal groups are processed differently:

• DO_NOT_UPDATE
  The coder will not process the PDU or signal. Data buffers will not be updated with received values and hence their content is undefined.
• SAMPLE_AND_HOLD
  The coder will stick to the last valid receive value. That means data buffers are not updated with the reveived values but remain in the state of the last valid received PDU/signal value. Valid denotes in this case the last receive operation with update bit set.
• USE_RECEIVED_VALUE
  The coder updates data buffers with the received values no matter if the update bit has been set or not.

Whenever data buffers are updated on receive, PDU or signal values may be read using adtf::devicetb::sdk::flexray::IFlexRayCoder::GetSignalValue().

Note

The API adtf::devicetb::sdk::flexray::IFlexRayCoder::GetPDUStatus() is not intended to get the status of received PDUs as one might guess. It is only relevant for PDU transmission, to have an indication if a PDU has indeed been updated and needs to be transmitted again. Indication is set when adtf::devicetb::sdk::flexray::IFlexRayCoder::SetSignalValue() has been called.

If the update bit is used according to the configuration of property flexray_updatebit_behavior the user will in any way get only valid PDUs and signals, but there is no access to the update bit itself. If this information is vital to your implementation feel free to access the raw values of a FlexRay frame as explained in Low level FlexRay data handling