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SerialPort: getSignals() method

Limited availability

This feature is not Baseline because it does not work in some of the most widely-used browsers.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Note: This feature is available in Dedicated Web Workers.

The SerialPort.getSignals() method of the SerialPort interface returns a Promise that resolves with an object containing the current state of the port's control signals.

Syntax

getSignals()

Parameters

None.

Return value

Returns a Promise that resolves with an object containing the following members:

clearToSend: A boolean indicating to the other end of a serial connection that is clear to send data.
dataCarrierDetect: A boolean that toggles the control signal needed to communicate over a serial connection.
dataSetReady: A boolean indicating whether the device is ready to send and receive data.
ringIndicator: A boolean indicating whether a ring signal should be sent down the serial connection.

Exceptions

InvalidStateError DOMException: Returned if the port is not open. Call SerialPort.open() to avoid this error.
NetworkError DOMException: Returned if the signals on the device could not be read.

Specifications

Specification
Web Serial API> # dom-serialport-getsignals>

Browser compatibility

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS
`getSignals`	89	89	No	75	No	No	No	No	No	No	No	No

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https://developer.mozilla.org/en-US/docs/Web/API/SerialPort/getSignals