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TWebUSBSerial

Below is a list of the most important properties methods and events for the TWebUSBSerial. TWebUSBSerial is using the Web Serial API This API currently is available in Chromium based browsers from version 89.

Properties for TWebUSBSerial

Property Description
AutoInitializePorts Automatically calls InitPorts when the application starts.
AutoOpenSelection Connect to the port automatically after selecting it.
AutoCloseSelection Close the current connection automatically when selecting another port.
Filters A collection of options to filter the serial port selection
Ports A collection of available ports that had been granted access to by the user.
SelectedPort The currently selected port.
SelectedPort A set of options that is used to connect to a port

Methods for TWebUSBSerial

Method Description
ClosePort(AForceClose: Boolean = False) Closes the connection of the selected port. This is an asynchronous method.
HasSerial Returns if the browser supports the Web Serial API.
InitPorts Initializes a list of ports that has already been granted access by the user previously. This is an asynchronous method.
OpenPort Opens connection to the selected port. This is an asynchronous method.
Read Read data from the serial port. This is an asynchronous method.
RequestPorts Requests access from the user to an available serial port. This is an asynchronous method.
Write(AData: TJSUint8Array) Sends a data array to the selected and connected serial port.

Events for TWebUSBSerial

Events Description
OnClosePort Event triggered when a port connection is closed
OnConnected Event triggered when a serial device is connected to computer and it is deceted by the browser.
OnDisconnected Event triggered when a serial device is removed from the computer.
OnError Event triggered when there is an error.
OnOpenPort Event triggered when a serial port connection is opened.
OnPortsInitialized Event triggered when the list of ports is initialized.
OnReadData Event triggered when data arrives from the serial port.
OnWriteData Event triggered when data is written to the serial port.