read

Reads the value of a GATT characteristic from the connected device. Use the device's commands and services to get valid serviceId and characteristicId values.

Signature

read(serviceId: string, characteristicId: string, duration?: number): Promise<string | undefined>

Parameters

Parameter	Type	Default	Description
serviceId	string	-	Service identifier (e.g. "battery", "progressor").
characteristicId	string	-	Characteristic identifier (e.g. "level", "rx", "tx").
duration	number	0	Milliseconds to wait before resolving. Use for async reads.

Returns

Promise<string | undefined> - Resolves with the characteristic value, or undefined if the read fails.

Example

await device.connect(
  async () => {
    const value = await device.read("battery", "level", 1000)
    console.log("Battery level:", value)
  },
  (err) => console.error(err),
)

Service and characteristic IDs

Use device.services to get valid serviceId and characteristicId values. Each service has an id (e.g. "battery", "progressor") and characteristics; each characteristic has an id (e.g. "level", "rx", "tx").