MARTe-Integrated-Components/Docs/Tutorial.md

# Tutorial: MARTe2 Integrated Components

This guide covers two complementary use-cases:

- **Part A** — Real-time signal streaming with `UDPStreamer` and the web client
- **Part B** — Signal tracing, forcing, and breakpoints with `DebugService`

---

## Part A: Streaming Signals with UDPStreamer

### A.1 Setting up the environment
2. Running the demo application
3. Visualising signals in the browser
4. Adding UDPStreamer to your own MARTe2 application
5. Streaming high-frequency packed signals

**Prerequisites:** MARTe2 and MARTe2-components must already be built.
See the [MARTe2 installation guide](https://vcis.f4e.europa.eu/marte2-docs/) if needed.

---

## 1. Environment Setup

Edit `marte_env.sh` in the repository root to point at your MARTe2 installations:

```bash
# marte_env.sh (key variables)
export MARTe2_DIR="$HOME/workspace/MARTe2"
export MARTe2_Components_DIR="$HOME/workspace/MARTe2-components"
```

Then source it in your shell:

```bash
cd /path/to/MARTe_IO_components
source marte_env.sh
```

Verify the environment is correct:

```bash
echo $MARTe2_DIR
ls $MARTe2_DIR/Build/x86-linux/App/MARTeApp.ex    # should exist
```

---

## 2. Running the Demo Application

The demo is in `Test/MARTeApp/`. It runs a 10 kHz MARTe2 application that streams:

- **Counter** and **Time** — scalar counters from the Linux timer
- **Sine1** — 1 Hz sine wave (float32, amplitude 10, quantized to uint16 on wire)
- **Sine2** — 0.3 Hz sine wave (float32, amplitude 5, raw float32 on wire)
- **Ch1**, **Ch2** — 1 kHz sine bursts packed as 1000 samples/packet (10 MSps)

Start everything with one command:

```bash
cd Test/MARTeApp
./run.sh --webui
```

The script will:
1. Build the UDPStreamer shared library.
2. Build the Go WebUI binary (first run only).
3. Start the WebUI relay on `http://localhost:8080`.
4. Launch the MARTe2 application.

Press `Ctrl+C` to stop both processes.

---

## 3. Visualising Signals in the Browser

Open `http://localhost:8080` in any modern browser.

### Add your first plot

1. Click **+ Add Plot** in the toolbar.
2. A blank plot panel appears with a "Drop signals here" hint.

### Plot a signal

1. In the left sidebar find **Sine1** (listed as `Sine1 · f32`).
2. Click and drag it onto the plot panel.
3. The sine wave appears immediately.

### Overlay multiple signals

Drag **Sine2** onto the same plot — it is added as a second trace.

### Adjust the time window

Use the **Window** dropdown in the top bar to change the rolling display window
(1 s, 5 s, 10 s, 30 s, 60 s).

### Plot layout

Use the layout buttons (`1×1`, `2×1`, `2×2`, …) to split the screen into multiple
plot panels. Each panel is independent — drag different signals onto each.

### High-frequency signals

Drag **Ch1** (shown as `Ch1 · [1000] f32`) onto a plot. Each UDP packet carries
1000 samples at 10 MSps; the WebUI reconstructs per-sample timestamps and displays
the continuous waveform.

### Export data

Click **⬇** on any plot to download the visible window as a CSV file.

---

## 4. Adding UDPStreamer to Your Own Application

### Step 1 — Declare the DataSource

Add UDPStreamer to the `+Data` section of your MARTe2 configuration:

```
+Data = {
    Class = ReferenceContainer
    DefaultDataSource = DDB

    +DDB = { Class = GAMDataSource }

    +Streamer = {
        Class          = UDPStreamer
        Port           = 44500
        MaxPayloadSize = 1400

        Signals = {
            Voltage = {
                Type     = float32
                Unit     = "V"
                RangeMin = -10.0
                RangeMax = 10.0
                QuantizedType = uint16      // 16-bit quantized on wire
            }
            Current = {
                Type = float32
                Unit = "A"
            }
        }
    }

    +Timings = { Class = TimingDataSource }
}
```

### Step 2 — Route signals with IOGAM

Use IOGAM to copy signals from your inter-GAM DDB into the Streamer:

```
+StreamerGAM = {
    Class = IOGAM
    InputSignals = {
        Voltage = { DataSource = DDB; Type = float32 }
        Current = { DataSource = DDB; Type = float32 }
    }
    OutputSignals = {
        Voltage = { DataSource = Streamer; Type = float32 }
        Current = { DataSource = Streamer; Type = float32 }
    }
}
```

Add `StreamerGAM` at the **end** of the thread's `Functions` list so it runs after
your control GAMs have written their outputs.

### Step 3 — Add the library to LD_LIBRARY_PATH

In your run script, add the UDPStreamer build directory:

```bash
export LD_LIBRARY_PATH="/path/to/Build/x86-linux/Components/DataSources/UDPStreamer:$LD_LIBRARY_PATH"
```

### Step 4 — Start the WebUI and connect

```bash
# From the Client/WebUI directory:
./udpstreamer-webui --streamer 127.0.0.1:44500 --listen :8080 --clientport 44900
```

Open `http://localhost:8080`, drag your signals onto a plot, and you're done.

---

## 5. Streaming High-Frequency Packed Signals

This section shows how to stream 1000 samples per RT cycle at 1 MSps.

### Overview

At 1 kHz RT rate with 1000 samples per cycle the effective sample rate is 1 MSps.
Each UDP packet carries a burst of 1000 samples; the client reconstructs timestamps
using the anchor timestamp and `SamplingRate`.

### Step 1 — Generate burst data with SineArrayGAM

`SineArrayGAM` (bundled in `UDPStreamer.so`) produces a continuous float32 array:

```
+Ch1GAM = {
    Class        = SineArrayGAM
    Frequency    = 1000.0       // 1 kHz signal
    Amplitude    = 1.0
    Phase        = 0.0
    SamplingRate = 1000000.0    // must match Streamer config below
    OutputSignals = {
        Ch1 = {
            DataSource         = DDB
            Type               = float32
            NumberOfDimensions = 1
            NumberOfElements   = 1000
        }
    }
}
```

### Step 2 — Add a time reference signal

Add a scalar time signal that will anchor the first sample's timestamp:

```
+TimerGAM = {
    Class = IOGAM
    InputSignals = {
        Time = { DataSource = Timer; Type = uint32; Frequency = 1000 }
    }
    OutputSignals = {
        Time = { DataSource = DDB; Type = uint32 }
    }
}
```

### Step 3 — Configure UDPStreamer for packed signals

```
+Streamer = {
    Class          = UDPStreamer
    Port           = 44500
    MaxPayloadSize = 1400

    Signals = {
        Time = { Type = uint32; Unit = "us" }   // time reference (scalar)

        Ch1 = {
            Type               = float32
            NumberOfDimensions = 1
            NumberOfElements   = 1000
            Unit               = "V"
            TimeMode           = FirstSample    // Time = timestamp of first sample
            TimeSignal         = Time
            SamplingRate       = 1000000.0      // Hz
        }
    }
}
```

### Step 4 — Wire everything in the thread

```
+Thread1 = {
    Class     = RealTimeThread
    Functions = { TimerGAM Ch1GAM StreamerGAM }
}
```

Where `StreamerGAM` is the IOGAM that copies `Time` and `Ch1` from DDB to Streamer.

### Step 5 — Fragmentation note

A single 1000-element float32 channel plus a uint32 time signal produces:

```
payload = 8 B (HRT) + 4 B (Time/uint32) + 4000 B (float32×1000) = 4012 B
```

With `MaxPayloadSize = 1400`:

```
fragments = ceil(4012 / 1383) = 3 datagrams per cycle
```

At 1 kHz that is 3000 UDP datagrams/second per channel — well within typical LAN capacity.

### Step 6 — Create the SineArrayGAM symlink

MARTe2 tries to `dlopen("SineArrayGAM.so")` the first time it encounters the class.
Create the symlink in your build directory:

```bash
UDPSTREAMER_LIB=/path/to/Build/x86-linux/Components/DataSources/UDPStreamer
ln -sf "${UDPSTREAMER_LIB}/UDPStreamer.so" "${UDPSTREAMER_LIB}/SineArrayGAM.so"
```

---

## 6. Writing a Custom UDP Client

A minimal Python client that receives and prints signal data:

```python
import socket, struct

MAGIC   = 0x53504455
HDR     = struct.Struct('<IBHHI')   # 17 bytes: magic, type, counter, fragIdx, total, payloadBytes
SERVER  = ('127.0.0.1', 44500)
MY_PORT = 44900

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.bind(('', MY_PORT))
sock.settimeout(5.0)

# Send CONNECT
sock.sendto(HDR.pack(MAGIC, 3, 0, 0, 1, 0), SERVER)
print("CONNECT sent")

reassembly = {}

while True:
    data, _ = sock.recvfrom(65536)
    if len(data) < 17:
        continue
    magic, ptype, counter, frag_idx, total_frags, payload_bytes = HDR.unpack_from(data)
    if magic != MAGIC:
        continue
    payload = data[17:17 + payload_bytes]

    # Accumulate fragments
    bucket = reassembly.setdefault((ptype, counter), {})
    bucket[frag_idx] = payload
    if len(bucket) < total_frags:
        continue
    full = b''.join(bucket[i] for i in range(total_frags))
    del reassembly[(ptype, counter)]

    if ptype == 1:   # CONFIG
        num_sigs = struct.unpack_from('<I', full)[0]
        print(f"CONFIG: {num_sigs} signals")
    elif ptype == 0: # DATA
        hrt = struct.unpack_from('<Q', full)[0]
        print(f"DATA counter={counter} hrt={hrt} payload={len(full)}B")
```

For a full-featured client with CONFIG parsing and dequantization see
[`Client/WebUI/protocol.go`](../Client/WebUI/protocol.go) (Go)
and the [Protocol reference](Protocol.md).

---

---

## Part B: Debugging with DebugService

### B.1 Add DebugService to Your Config

Add it as a **sibling** of the `+App` node (not inside it):

```text
+DebugService = {
    Class       = DebugService
    ControlPort = 8080
    UdpPort     = 8081
    LogPort     = 8082
}

+Logger = {
    Class = TcpLogger
    Port  = 8082
}

+App = {
    Class = RealTimeApplication
    ...
}
```

Call `SetFullConfig(cdb)` after `ConfigureApplication()` to enable the `CONFIG` and `INFO` commands.

### B.2 Start the Debug Web Client

```bash
cd Client/debugger
go build ./...
./debugger --listen :9090
```

Open `http://localhost:9090` in any browser.

### B.3 Exploring the Object Tree

The **Application Tree** panel on the left mirrors your live MARTe2 `ObjectRegistryDatabase`.

1. Expand `Root → App → Data` to find data sources.
2. Click **Info** next to any node to see its class, config, and signals.
3. Click **List** to show immediate children.

### B.4 Real-Time Signal Tracing

1. Locate a signal, e.g. `Root.App.Data.Timer.Counter`.
2. Click **Trace**. The signal appears in the **Traced Signals** list with its live last value.
3. Click **Plot** to open it in the real-time graph. Use **Follow** to keep the time axis scrolling.
4. To set decimation (e.g. every 10th sample):
   ```
   TRACE App.Data.Timer.Counter 1 10
   ```
5. Click **Trace** again (or send `TRACE … 0`) to stop.

### B.5 Signal Forcing

1. Find a signal, e.g. `Root.App.Data.DDB.Counter`.
2. Click **Force**, enter a value (e.g. `9999`), click **Apply**.
3. The signal is locked at that value every RT cycle.
4. Click **Unforce** to release.

### B.6 Conditional Breakpoints

1. Click **Break** next to a signal.
2. Select an operator (`>`, `<`, `==`, `>=`, `<=`, `!=`) and enter a threshold.
3. When the condition fires, the application pauses. The status bar shows **PAUSED**.
4. Use **Step** to advance one cycle at a time, or **Resume** to continue.
5. Click **Break OFF** to clear.

### B.7 Execution Stepping

While paused (after a breakpoint or manual **Pause**):

1. Enter a step count (e.g. `5`) and click **Step**.
2. The RT loop runs exactly 5 output-broker cycles, then pauses again.
3. The status SSE event (`{"type":"status","remaining":…}`) keeps the UI updated.

### B.8 Scripted / Programmatic Access

Both `DebugService` and the web client accept plain-text TCP commands:

```bash
# Direct TCP
echo -e "DISCOVER\nTRACE App.Data.DDB.Counter 1" | nc localhost 8080

# Via web client API
curl -s -X POST http://localhost:9090/api/command \
     -H "Content-Type: text/plain" \
     -d "DISCOVER"
```

See `Docs/DebugService.md` for the full command reference.

---

## Part C: Using UDPStreamer and DebugService Together

Both can run simultaneously in the same application:

```text
+DebugService = { Class = DebugService; ControlPort = 8080; UdpPort = 8081; LogPort = 8082 }
+Logger       = { Class = TcpLogger; Port = 8082 }

+App = {
    Class = RealTimeApplication
    +Data = {
        Class = ReferenceContainer
        DefaultDataSource = DDB
        +DDB      = { Class = GAMDataSource }
        +Streamer = { Class = UDPStreamer; Port = 44500; MaxPayloadSize = 1400; ... }
        +Timings  = { Class = TimingDataSource }
    }
    ...
}
```

- `UDPStreamer` provides continuous high-speed streaming of selected signals.
- `DebugService` provides on-demand tracing, forcing, and breakpoints for any signal.
- Both use the UDPS binary protocol format (see `Docs/Protocol.md`).

---

## Troubleshooting

| Symptom | Cause | Fix |
|---------|-------|-----|
| `Failed dlopen(): UDPStreamer.so` | Library not in `LD_LIBRARY_PATH` | Source `env.sh`; add build dir |
| `Failed dlopen(): SineArrayGAM.so` | Symlink missing | `ln -sf UDPStreamer.so SineArrayGAM.so` in build dir |
| WebUI shows "No data" | UDPStreamer not running / wrong port | Check port numbers; check MARTe2 logs |
| Plots only show ~167 ms of HF data | Browser buffer too small | Reduce decimation or increase `TEMPORAL_CAP` in JS |
| Fragmentation error / missing data | MTU too small | Reduce `MaxPayloadSize` to 1200 or smaller |
| DebugService: DISCOVER returns empty | `PatchRegistry` called too late | Ensure `DebugService` is initialised before `ConfigureApplication()` |
| Integration tests timeout | MARTe2 libs not on `LD_LIBRARY_PATH` | Source `env.sh` before running tests |