CHIP Linux Energy Management Example

An example showing the use of CHIP on the Linux. The document will describe how to build and run CHIP Linux Energy Management Example on Raspberry Pi. This doc is tested on Ubuntu for Raspberry Pi Server 20.04 LTS (aarch64) and Ubuntu for Raspberry Pi Desktop 20.10 (aarch64)

To cross-compile this example on x64 host and run on NXP i.MX 8M Mini EVK, see the associated README document for details.

• CHIP Linux Energy Management Example
  • Building
  • Commandline arguments
  • Running the Complete Example on Raspberry Pi 4
  • Running RPC Console
  • Device Tracing
  • Python Test Cases
    • Running the test cases:
  • CHIP-REPL Interaction
    • Building chip-repl:
    • Activating python virtual env
    • Interacting with CHIP-REPL and the example app
    • Using chip-repl to Fake a charging session

Building

• Install tool chain

    $ sudo apt-get install git gcc g++ python pkg-config libssl-dev libdbus-1-dev libglib2.0-dev ninja-build python3-venv python3-dev unzip
  

• Build the example application:

    $ cd ~/connectedhomeip/examples/energy-management-app/linux
    $ git submodule update --init
    $ source third_party/connectedhomeip/scripts/activate.sh
    $ gn gen out/debug
    $ ninja -C out/debug
  

• To delete generated executable, libraries and object files use:

    $ cd ~/connectedhomeip/examples/energy-management-app/linux
    $ rm -rf out/
  

• Build the example with pigweed RPC

    $ cd ~/connectedhomeip/examples/energy-management-app/linux
    $ git submodule update --init
    $ source third_party/connectedhomeip/scripts/activate.sh
    $ gn gen out/debug --args='import("//with_pw_rpc.gni")'
    $ ninja -C out/debug
  

Commandline arguments

• --wifi

  Enables WiFi management feature. Required for WiFi commissioning.

• --thread

  Enables Thread management feature, requires ot-br-posix dbus daemon running. Required for Thread commissioning.

• --ble-device <interface id>

  Use specific bluetooth interface for BLE advertisement and connections.

  interface id: the number after hci when listing BLE interfaces by hciconfig command, for example, --ble-device 1 means using hci1 interface. Default: 0.

Running the Complete Example on Raspberry Pi 4

If you want to test Echo protocol, please enable Echo handler

gn gen out/debug --args='chip_app_use_echo=true'
ninja -C out/debug

• Prerequisites

  1. A Raspberry Pi 4 board
  2. A USB Bluetooth Dongle, Ubuntu desktop will send Bluetooth advertisement, which will block CHIP from connecting via BLE. On Ubuntu server, you need to install pi-bluetooth via APT.
  3. Ubuntu 20.04 or newer image for ARM64 platform.

• Building

  Follow Building section of this document.

• Running

  • [Optional] Plug USB Bluetooth dongle

    • Plug USB Bluetooth dongle and find its bluetooth device number. The number after hci is the bluetooth device number, 1 in this example.

        $ hciconfig
        hci1:	Type: Primary  Bus: USB
            BD Address: 00:1A:7D:AA:BB:CC  ACL MTU: 310:10  SCO MTU: 64:8
            UP RUNNING PSCAN ISCAN
            RX bytes:20942 acl:1023 sco:0 events:1140 errors:0
            TX bytes:16559 acl:1011 sco:0 commands:121 errors:0
      
        hci0:	Type: Primary  Bus: UART
            BD Address: B8:27:EB:AA:BB:CC  ACL MTU: 1021:8  SCO MTU: 64:1
            UP RUNNING PSCAN ISCAN
            RX bytes:8609495 acl:14 sco:0 events:217484 errors:0
            TX bytes:92185 acl:20 sco:0 commands:5259 errors:0
      

    • Run Linux Energy Management Example App

        $ cd ~/connectedhomeip/examples/energy-management-app/linux
        $ sudo out/debug/chip-energy-management-app --ble-device [bluetooth device number]
        # In this example, the device we want to use is hci1
        $ sudo out/debug/chip-energy-management-app --ble-device 1
      

    • Test the device using ChipDeviceController on your laptop / workstation etc.

Running RPC Console

• As part of building the example with RPCs enabled the chip_rpc python interactive console is installed into your venv. The python wheel files are also created in the output folder: out/debug/chip_rpc_console_wheels. To install the wheel files without rebuilding: pip3 install out/debug/chip_rpc_console_wheels/*.whl

• To use the chip-rpc console after it has been installed run: chip-console -s localhost:33000 -o /<YourFolder>/pw_log.out

• Then you can Get and Set the Energy Management using the RPCs: rpcs.chip.rpc.EnergyManagement.Get()

Device Tracing

Device tracing is available to analyze the device performance. To turn on tracing, build with RPC enabled. See Building with RPC enabled.

Obtain tracing json file.

    $ ./{PIGWEED_REPO}/pw_trace_tokenized/py/pw_trace_tokenized/get_trace.py -s localhost:33000 \
     -o {OUTPUT_FILE} -t {ELF_FILE} {PIGWEED_REPO}/pw_trace_tokenized/pw_trace_protos/trace_rpc.proto

Python Test Cases

When you want to test this cluster you can use chip-repl or chip-tool by hand. CHIP-REPL is slightly easier to interact with when dealing with some of the complex structures.

There are several test scripts provided for EVSE (in src/python_testing):

• TC_EEVSE_2_2: This validates the primary functionality
• TC_EEVSE_2_3: This validates Get/Set/Clear target commands
• TC_EEVSE_2_4: This validates Faults
• TC_EEVSE_2_5: This validates EVSE diagnostic command (optional)

These scripts require the use of Test Event Triggers via the GeneralDiagnostics cluster on Endpoint 0. This requires an enableKey (16 bytes) and a set of reserved int64_t test event trigger codes.

By default the test event support is not enabled, and when compiling the example app you need to add chip_enable_energy_evse_trigger=true to the gn args.

      $ gn gen out/debug --args='chip_enable_energy_evse_trigger=true'
      $ ninja -C out/debug

Once the application is built you also need to tell it at runtime what the chosen enable key is using the --enable-key command line option.

      $ ./chip-energy-management-app --enable-key 000102030405060708090a0b0c0d0e0f

Running the test cases:

From the top-level of the connectedhomeip repo type:

     $ python src/python_testing/TC_EEVSE_2_2.py --endpoint 1 -m on-network -n 1234 -p 20202021 -d 3840 --hex-arg enableKey:000102030405060708090a0b0c0d0e0f

• Note that the --endpoint 1 must be used with the example, since the EVSE cluster is on endpoint 1. The --hex-arg enableKey:<key> value must match the --enable-key <key> used on chip-energy-management-app args.

CHIP-REPL Interaction

• See chip-repl documentation in Matter_REPL_Intro

Building chip-repl:

    $ ./build_python.sh -i <path_to_out_folder>

Activating python virtual env

• You need to repeat this step each time you start a new shell.

    $ source <path_to_out_folder>/bin/activate

Interacting with CHIP-REPL and the example app

• Step 1: Launch the example app

    $ ./chip-energy-management-app --enable-key 000102030405060708090a0b0c0d0e0f

• Step 2: Launch CHIP-REPL

    $ chip-repl

• Step 3: (In chip-repl) Commissioning OnNetwork

    devCtrl.CommissionOnNetwork(1234,20202021)   # Commission with NodeID 1234
Established secure session with Device
Commissioning complete
Out[2]: <chip.native.PyChipError object at 0x7f2432b16140>

• Step 4: (In chip-repl) Read EVSE attributes

    # Read from NodeID 1234, Endpoint 1, all attributes on EnergyEvse cluster
    await devCtrl.ReadAttribute(1234,[(1, chip.clusters.EnergyEvse)])

{
│   1: {
│   │   <class 'chip.clusters.Objects.EnergyEvse'>: {
│   │   │   <class 'chip.clusters.Attribute.DataVersion'>: 3790455237,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.ChargingEnabledUntil'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.FaultState'>: <FaultStateEnum.kNoError: 0>,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.NextChargeStartTime'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.StateOfCharge'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.MaximumChargeCurrent'>: 0,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.ApproximateEVEfficiency'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.BatteryCapacity'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.AcceptedCommandList'>: [
... │   │   ],
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.MinimumChargeCurrent'>: 6000,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.NextChargeTargetSoC'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.SessionDuration'>: 758415333,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.NumberOfWeeklyTargets'>: 0,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.FeatureMap'>: 1,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.GeneratedCommandList'>: [
...
│   │   │   ],
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.State'>: <StateEnum.kNotPluggedIn: 0>,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.SessionID'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.SessionEnergyCharged'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.VehicleID'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.NextChargeRequiredEnergy'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.SessionEnergyDischarged'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.AttributeList'>: [
... │   │   ],
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.NextChargeTargetTime'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.CircuitCapacity'>: 0,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.DischargingEnabledUntil'>: Null,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.SupplyState'>: <SupplyStateEnum.kDisabled: 0>,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.RandomizationDelayWindow'>: 600,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.MaximumDischargeCurrent'>: 0,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.NumberOfDailyTargets'>: 1,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.UserMaximumChargeCurrent'>: 80000,
│   │   │   <class 'chip.clusters.Objects.EnergyEvse.Attributes.ClusterRevision'>: 2
│   │   }
│   }
}

• Step 5: Setting up a subscription so that attributes updates are sent automatically

   reportingTimingParams = (3, 60) # MinInterval = 3s, MaxInterval = 60s
   subscription = await devCtrl.ReadAttribute(1234,[(1, chip.clusters.EnergyEvse)], reportInterval=reportingTimingParams)

• Step 6: Send an EnableCharging command which lasts for 60 seconds The EnableCharging takes an optional chargingEnabledUntil parameter which allows the charger to automatically disable itself at some preset time in the future. Note that it uses Epoch_s (which is from Jan 1 2000) which is a uint32_t in seconds.

   from datetime import datetime, timezone, timedelta
   epoch_end = int((datetime.now(tz=timezone.utc) + timedelta(seconds=60) - datetime(2000, 1, 1, 0, 0, 0, 0, timezone.utc)).total_seconds())

   await devCtrl.SendCommand(1234, 1, chip.clusters.EnergyEvse.Commands.EnableCharging(chargingEnabledUntil=epoch_end,minimumChargeCurrent=2000,maximumChargeCurrent=25000),timedRequestTimeoutMs=3000)

The output should look like:

Attribute Changed:
{
│   'Endpoint': 1,
│   'Attribute': <class 'chip.clusters.Objects.EnergyEvse.Attributes.SupplyState'>,
│   'Value': <SupplyStateEnum.kChargingEnabled: 1>
}
Attribute Changed:
{
│   'Endpoint': 1,
│   'Attribute': <class 'chip.clusters.Objects.EnergyEvse.Attributes.MinimumChargeCurrent'>,
│   'Value': 2000
}
Attribute Changed:
{
│   'Endpoint': 1,
│   'Attribute': <class 'chip.clusters.Objects.EnergyEvse.Attributes.ChargingEnabledUntil'>,
│   'Value': 758416066
}

After 60 seconds the charging should automatically become disabled:

Attribute Changed:
{
│   'Endpoint': 1,
│   'Attribute': <class 'chip.clusters.Objects.EnergyEvse.Attributes.SupplyState'>,
│   'Value': <SupplyStateEnum.kDisabled: 0>
}
Attribute Changed:
{
│   'Endpoint': 1,
│   'Attribute': <class 'chip.clusters.Objects.EnergyEvse.Attributes.DischargingEnabledUntil'>,
│   'Value': 0
}
Attribute Changed:
{
│   'Endpoint': 1,
│   'Attribute': <class 'chip.clusters.Objects.EnergyEvse.Attributes.MinimumChargeCurrent'>,
│   'Value': 0
}
Attribute Changed:
{
│   'Endpoint': 1,
│   'Attribute': <class 'chip.clusters.Objects.EnergyEvse.Attributes.ChargingEnabledUntil'>,
│   'Value': 0
}

Note that you can omit the chargingEnabledUntil argument and it will charge indefinitely.

Using chip-repl to Fake a charging session

If you haven't implemented a real EVSE but want to simulate plugging in an EV then you can use a few of the test event triggers to simulate these scenarios.

The test event triggers values can be found in: EnergyEvseTestEventTriggerDelegate.h

• 0x0099000000000000 - Simulates the EVSE being installed on a 32A supply
• 0x0099000000000002 - Simulates the EVSE being plugged in (this should generate an EVConnected event)
• 0x0099000000000004 - Simulates the EVSE requesting power

To send a test event trigger to the app, use the following commands (in chip-repl):

    # send 1st event trigger to 'install' the EVSE on a 32A supply
    await devCtrl.SendCommand(1234, 0, chip.clusters.GeneralDiagnostics.Commands.TestEventTrigger(enableKey=bytes([b for b in range(16)]), eventTrigger=0x0099000000000000))

    # send 2nd event trigger to plug the EV in
    await devCtrl.SendCommand(1234, 0, chip.clusters.GeneralDiagnostics.Commands.TestEventTrigger(enableKey=bytes([b for b in range(16)]), eventTrigger=0x0099000000000002))

Now send the enable charging command (omit the chargingEnabledUntil arg this time):

    await devCtrl.SendCommand(1234, 1, chip.clusters.EnergyEvse.Commands.EnableCharging(minimumChargeCurrent=2000,maximumChargeCurrent=25000),timedRequestTimeoutMs=3000)

Now send the test event trigger to simulate the EV asking for demand:

    # send 2nd event trigger to plug the EV in
    await devCtrl.SendCommand(1234, 0, chip.clusters.GeneralDiagnostics.Commands.TestEventTrigger(enableKey=bytes([b for b in range(16)]), eventTrigger=0x0099000000000004))

    # Read the events
    await devCtrl.ReadEvent(1234,[(1, chip.clusters.EnergyEvse,1)])

[
│   EventReadResult(
│   │   Header=EventHeader(
│   │   │   EndpointId=1,
│   │   │   ClusterId=153,
│   │   │   EventId=0,
│   │   │   EventNumber=65538,
│   │   │   Priority=<EventPriority.INFO: 1>,
│   │   │   Timestamp=1705102500069,
│   │   │   TimestampType=<EventTimestampType.EPOCH: 1>
│   │   ),
│   │   Status=<Status.Success: 0>,
│   │   Data=EVConnected(
│   │   │   sessionID=0
│   │   )
│   ),
│   EventReadResult(
│   │   Header=EventHeader(
│   │   │   EndpointId=1,
│   │   │   ClusterId=153,
│   │   │   EventId=2,
│   │   │   EventNumber=65539,
│   │   │   Priority=<EventPriority.INFO: 1>,
│   │   │   Timestamp=1705102801764,
│   │   │   TimestampType=<EventTimestampType.EPOCH: 1>
│   │   ),
│   │   Status=<Status.Success: 0>,
│   │   Data=EnergyTransferStarted(
│   │   │   sessionID=0,
│   │   │   state=<StateEnum.kPluggedInCharging: 3>,
│   │   │   maximumCurrent=25000
│   │   )
│   )
]

• We can see that the EventNumber 65538 was sent when the vehicle was plugged in, and a new sessionID=0 was created.
• We can also see that the EnergyTransferStarted was sent in EventNumber 65539

What happens when we unplug the vehicle?

    await devCtrl.SendCommand(1234, 0, chip.clusters.GeneralDiagnostics.Commands.TestEventTrigger(enableKey=bytes([b for b in range(16)]), eventTrigger=0x0099000000000001))

When we re-read the events:

[
│   EventReadResult(
│   │   Header=EventHeader(
│   │   │   EndpointId=1,
│   │   │   ClusterId=153,
│   │   │   EventId=3,
│   │   │   EventNumber=65540,
│   │   │   Priority=<EventPriority.INFO: 1>,
│   │   │   Timestamp=1705102996749,
│   │   │   TimestampType=<EventTimestampType.EPOCH: 1>
│   │   ),
│   │   Status=<Status.Success: 0>,
│   │   Data=EnergyTransferStopped(
│   │   │   sessionID=0,
│   │   │   state=<StateEnum.kPluggedInCharging: 3>,
│   │   │   reason=<EnergyTransferStoppedReasonEnum.kOther: 2>,
│   │   │   energyTransferred=0
│   │   )
│   ),
│   EventReadResult(
│   │   Header=EventHeader(
│   │   │   EndpointId=1,
│   │   │   ClusterId=153,
│   │   │   EventId=1,
│   │   │   EventNumber=65541,
│   │   │   Priority=<EventPriority.INFO: 1>,
│   │   │   Timestamp=1705102996749,
│   │   │   TimestampType=<EventTimestampType.EPOCH: 1>
│   │   ),
│   │   Status=<Status.Success: 0>,
│   │   Data=EVNotDetected(
│   │   │   sessionID=0,
│   │   │   state=<StateEnum.kPluggedInCharging: 3>,
│   │   │   sessionDuration=0,
│   │   │   sessionEnergyCharged=0,
│   │   │   sessionEnergyDischarged=0
│   │   )
│   )
]

• In EventNumber 65540 we had an EnergyTransferStopped event with reason kOther.

  This was a rather abrupt end to a charging session (normally we would see the EVSE or EV decide to stop charging), but this demonstrates the cable being pulled out without a graceful charging shutdown.

• In EventNumber 65541 we had an EvNotDetected event showing that the state was kPluggedInCharging prior to the EV being not detected (normally in a graceful shutdown this would be kPluggedInNoDemand or kPluggedInDemand).