SensWear TypeScript SDK

TypeScript SDK for connecting to SensWear hardware from React Native mobile apps over BLE.

This SDK mirrors the SensWear Python SDK and uses react-native-ble-plx for BLE access. It supports:

• Discovering and connecting to SensWear devices advertising as Sens Wear ..., SensWear ..., or SenseWear ....
• Reading and subscribing to the battery gauge characteristic.
• Reading and subscribing to charger state.
• Reading and writing the RGBW LED color characteristic.
• Subscribing to IMU quaternion and linear acceleration notifications.
• Reading, configuring, and subscribing to temperature notifications.
• Writing haptic vibration patterns.

Install

npm install senswear react-native-ble-plx

Follow the react-native-ble-plx iOS, Android, and permission setup for your app. The SDK does not request Bluetooth permissions for you.

Basic usage

import { BleManager } from "react-native-ble-plx";
import { SenswearClient } from "senswear";

const manager = new BleManager();
const device = new SenswearClient(null, { manager });

await device.connect();

const battery = await device.battery.read();
console.log(`Battery: ${battery.stateOfChargePercent.toFixed(1)}%`);
console.log(`Voltage: ${battery.voltageMv} mV`);

await device.disconnect();

To connect to a known BLE device id or exact advertised name:

const device = new SenswearClient("Sens Wear (Regulator)", { manager });
await device.connect();

Discovery

import { SenswearClient } from "senswear";

const devices = await SenswearClient.discover({ timeoutMs: 5000 });
for (const device of devices) {
  console.log(device.id, device.name, device.rssi);
}

If you already own a BleManager, pass it to avoid creating a short-lived manager:

const devices = await SenswearClient.discover({ manager });

Battery gauge

const state = await device.battery.read();
console.log(state.temperatureC);
console.log(state.stateOfChargePercent);

await device.battery.subscribe((sample) => {
  console.log(sample.toDict());
});

await device.battery.unsubscribe();

Battery raw fields match the firmware payload:

| SDK field | Unit | | --- | --- | | temperatureDeciC | 0.1 degrees Celsius | | voltageMv | millivolts | | averageCurrentMa | milliamps | | averagePowerMw | milliwatts | | stateOfChargeDeciPercent | 0.1 percent | | nominalAvailableCapacityMah | mAh | | fullBatteryCapacityMah | mAh | | remainingCapacityMah | mAh |

Python-compatible snake_case aliases are also available, for example state.state_of_charge_percent.

Charger

const state = await device.charger.read();
console.log(state.powerGood);
console.log(state.charging);
console.log(state.charged);
console.log(state.hasFault);

The charger payload is a 32-bit flags value. Convenience getters expose the firmware bits as booleans:

buttonPressed, wake1, wake2, shipmentMode, shutdownMode, powerGood, charging, charged, thermalRegulation, batteryUvlo, thermalNormal, thermalWarmOrHot, thermalWarm, thermalCool, safetyTimerFault, thermalSystemFault, batteryUvloFault, batteryOcpFault, and hasFault.

LED

import { LedColor } from "senswear";

await device.led.set(new LedColor(255, 0, 0));
await device.led.set("#00ff00");
await device.led.set([0, 0, 255, 0]);
await device.led.set(0x000000ff);

const current = await device.led.read();
console.log(current.toHex({ includeWhite: true }));

await device.led.off();

The LED characteristic is a 4-byte little-endian RGBW value: red byte 0, green byte 1, blue byte 2, white byte 3.

IMU

The IMU service is notify-only. Subscribing to either IMU characteristic enables firmware-side streaming.

await device.imu.subscribeQuaternion((sample) => {
  console.log(sample.toTuple());
  console.log(sample.accuracyDegrees);
});

await device.imu.subscribeLinearAcceleration((sample) => {
  console.log(sample.toTuple());
});

await device.imu.unsubscribeAll();

Quaternion values are raw signed Q14 with normalized getters xFloat, yFloat, zFloat, wFloat; accuracy is raw unsigned Q14 radians with accuracyRadians and accuracyDegrees.

Linear acceleration exposes raw x, y, z and scaled xG, yG, zG using value / 4096.0.

Temperature

await device.temperature.setSamplingRateHz(2);

const latest = await device.temperature.read();
console.log(latest.temperatureC);

await device.temperature.subscribe((sample) => {
  console.log(sample.temperatureF);
});

await device.temperature.unsubscribe();

setSamplingRateHz() and setTransferInterval() write nonzero little-endian uint16 values.

Haptic

import { HapticFrame, HapticPattern } from "senswear";

await device.haptic.vibrate(150, 255);

const pattern = HapticPattern.fromFrames([
  new HapticFrame(80, 220),
  new HapticFrame(60, 0),
  new HapticFrame(120, 180),
]);

await device.haptic.play(pattern);

Pattern payload layout:

| Field | Format | | --- | --- | | version | byte, currently 1 | | flags | byte, reserved, send 0 | | frame_count | little-endian uint16, 1 to 64 | | frame duration_ms | little-endian uint16, nonzero | | frame intensity | byte, 0 to 255 |

An intensity of 0 acts as an off/pause frame.

Development

npm install
npm test
npm run build
npm publish