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  • Closing the port after a read or write operation
  • Features specific to Android and Android widget
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Stored procedures
Closes the specified serial port, parallel port or infrared port.
Remarks:
  • A port must be closed as soon as it is no longer used.
  • AndroidAndroid Widget Only serial ports are supported.
Example
PortNum is int
PortNum = sOpen("COM1", 2000, 2000) // Open COM1
IF PortNum <> 0 THEN
// Configure COM1: Rate 9600, even parity,
// 8 data bits, 1 stop bit
sParameter(PortNum, 9600, 1, 8, 0)
// Rest of process...
sClose(PortNum) // Close COM1
ELSE
Error("Error while opening COM1")
END
Syntax
sClose(<Port number>)
<Port number>: Integer
Identifier of the port used:
  • Port number:
    • Number of the serial port: 1, 2, 3, ... 32 for COM1, COM2, COM3, ... COM32.
    • Number of the parallel port: -1, -2, -3 or -4 for LPT1, LPT2, LPT3 or LPT4.
    • Number of the infrared port: 1, 2, 3, ... 32 for IR1, IR2, IR3, ... IR32.
  • Port identifier returned by sOpen (if this function was called with a port name).
    AndroidAndroid Widget Only this type of parameter is available.
Remarks

Closing the port after a read or write operation

If sClose is run just after sWrite ou sRead, some characters may not be written or read. Indeed, sClose can close the port before all the characters are written or read. To avoid this behavior, use Multitask.
Res = sOpen("COM2", 2000, 2000)
IF Res <> 0 THEN
sParameter(Res, 9600, 0, 8, 0)
sWrite(Res, Str)
Multitask()
sClose(Res)
END
AndroidAndroid Widget

Features specific to Android and Android widget

In Android and Android widget mode, the serial and parallel port functions can be used:
  • Only on serial (not parallel or infrared) ports.
  • Only with devices that support the CDC/ACM protocol (Arduino ATmega32U4) and the following USB to serial converter chips:
    • FTDI FT232R, FT232H, FT2232H, FT4232H, FT230X, FT231X, FT234XD
    • Silabs CP210x
    • Qinheng CH340, CH341A
    • Prolific PL2303
Business / UI classification: Business Logic
Component: wd290com.dll
Minimum version required
  • Version 9
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Last update: 05/26/2022

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