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SerialPort: setSignals() method

Limited availability

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

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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 setSignals() method of the SerialPort interface sets control signals on the port and returns a Promise that resolves when they are set.

setSignals()
setSignals(options)

An object with any of the following values:

dataTerminalReady: A boolean indicating whether to invoke the operating system to either assert (if true) or de-assert (if false) the "data terminal ready" or "DTR" signal on the serial port.
requestToSend: A boolean indicating whether to invoke the operating system to either assert (if true) or de-assert (if false) the "request to send" or "RTS" signal on the serial port.
break: A boolean indicating whether to invoke the operating system to either assert (if true) or de-assert (if false) the "break" signal on the serial port.

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 set.

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

	Desktop					Mobile
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	WebView on iOS
`setSignals`	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/setSignals