Configuration

After connecting, you can change settings such as LED brightness by sending commands to the device.

Sending a command

Use the SDK's low-level sending API to send raw command bytes to process ID 0. Include a trailing null byte (\0). Awaiting the send does not wait for the command's result. Handle that result through payload callbacks.

The following example sets LED brightness to 10:

Python

# Set LED brightness to 10.
command = b"set led_brght 10\0"

await device.send(command)

Android

// Set LED brightness to 10.
val command = "set led_brght 10"

val payload = "$command\u0000".toByteArray(Charsets.UTF_8)
lifecycleScope.launch { device.send(payload, processId = 0) }

Apple Platforms

// Set LED brightness to 10.
let command = "set led_brght 10"

let payload: [UInt8] = Array("\(command)\0".utf8)
try await device.send(payload, processId: 0)

Flutter

import 'dart:convert';
import 'dart:typed_data';

// Set LED brightness to 10.
const command = 'set led_brght 10';

final payload = Uint8List.fromList([...utf8.encode(command), 0]);
await device.send(payload, processId: 0);

Unity

using UnityEngine;

public class ConfigureAidlab : MonoBehaviour {
    private Aidlab.AidlabSDK sdk;

    void Start() {
        Aidlab.AidlabSDK.init();
        sdk = FindAnyObjectByType<Aidlab.AidlabSDK>();
        if (sdk == null) {
            return;
        }

        sdk.Connected += Configure;
        if (sdk.IsSdkInitialized) {
            Configure();
        }
    }

    void Configure() {
        // Set LED brightness to 10.
        sdk.SendCommand("set led_brght 10");
    }
}

Receiving the response

Listen for payload callbacks in your delegate and interpret the response according to the command you sent. For the LED command above, the response is UTF-8 text followed by a newline:

led_brght = 10

The SDK preserves the response bytes. The examples below log them in hexadecimal so binary responses can be inspected too:

Python

def did_receive_payload(self, device, pid, payload, options=0):
    print(f"PID {pid}: {payload.hex(' ')} (options={options})")

Android

override fun didReceivePayload(
    device: Device,
    pid: Int,
    payload: ByteArray,
    options: Long,
) {
    val hex = payload.joinToString(" ") { "%02x".format(it.toInt() and 0xff) }
    println("PID $pid: $hex (options=$options)")
}

Apple Platforms

import Foundation

func didReceivePayload(_ device: Device, pid: UInt16, payload: Data, options: UInt64) {
    let hex = payload.map { String(format: "%02x", $0) }.joined(separator: " ")
    print("PID \(pid): \(hex) (options=\(options))")
}

Flutter

@override
void didReceivePayload(Device device, int pid, Uint8List payload, int options) {
  final hex = payload.map((byte) => byte.toRadixString(16).padLeft(2, '0')).join(' ');
  print('PID $pid: $hex (options=$options)');
}

Unity

sdk.PayloadReceived += (pid, payload, options) => {
    var hex = System.BitConverter.ToString(payload).Replace("-", " ");
    UnityEngine.Debug.Log($"PID {pid}: {hex} (options={options})");
};

One command can produce several callbacks. The LED command produces a process-creation notification on PID 0, the text response on the assigned PID, and a process-termination notification on PID 0.

Lifecycle notifications on PID 0 start with a status byte: 0 process created, 1 command rejected, 2 process ended, 3 stop rejected. Bytes 1–2 hold the PID, little-endian. An unknown command is rejected with the single byte 1. Send the next command after the previous one is created or rejected.

Output from child processes retains the PID of the process whose output they inherited. Before firmware 2.2.18, all responses use PID 0; interpret them in the context of the command you sent.

Each callback delivers the original bytes and options. Chunks may split text lines and UTF-8 characters. Combine chunks by PID and decode incrementally when you need a text response.

Process stderr is delivered separately through didReceiveProcessError (did_receive_process_error in Python), with the same device, PID, payload and options arguments. Aidlab 1 does not emit stderr. processDidTerminate(device, pid) (process_did_terminate) reports process termination.

Command compatibility

The table below shows command examples and their availability on each device.

Command	What it does	Aidlab 1	Aidlab 2
set led_brght <value>	Sets LED brightness from 1 to 16.	Yes	Yes
set ecg_fs <value>	Sets ECG sampling frequency to 250, 500, or 1000 Hz.	Yes	Yes
ping	Returns a ping response.	Yes	Yes
ls /data	Lists files in the device's /data directory.	No	Yes
echo hello > /data/example.txt	Creates or overwrites a file with hello.	No	Yes
echo again >> /data/example.txt	Appends again to the file.	No	Yes
cat /data/example.txt	Returns the file's contents through payload callbacks.	No	Yes
ps	Lists running processes and their PIDs.	No	Yes
kill <pid>	Requests termination of a process.	Yes	Yes
timeout 10 ping	Runs ping with a ten-second time limit.	No	Yes

ECG sampling frequency

Changing the ECG sampling frequency may break compatibility with official apps. The device restarts to apply a new value. On Aidlab 2, heart rate, RR and respiration are unaffected.