CommAPI Examples

Introduction

This site shows you some examples for CommAPI. You will also need the following snippet for all examples:

#include "CommInterface.au3"
#AutoIt3Wrapper_Au3Check_Parameters=-q -d -w 1 -w 2 -w 3 -w- 4 -w 5 -w 6 -w- 7

Main()

Func Main()
	Local $sResult = Example()
	Switch @error
		Case 0
			MsgBox(64, "Result", $sResult)
		Case -1
			MsgBox(32, "Error", _WinAPI_GetLastErrorMessage())
		Case -2
			MsgBox(32, "Timeout", $sResult)
		Case Else
			MsgBox(32, "Error", "Error " & @error & " in line " & @extended)
	EndSwitch
EndFunc

First example

Func Example()
	Local Const $iPort = 1
	Local Const $iBaud = 9600
	Local Const $iParity = 0
	Local Const $iByteSize = 8
	Local Const $iStopBits = 1
	Local Const $sCommand = "Command" & @CRLF

	Local $hFile = _CommAPI_OpenCOMPort($iPort, $iBaud, $iParity, $iByteSize, $iStopBits)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_ClearCommError($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_PurgeComm($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_TransmitString($hFile, $sCommand)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	Local $sResult = _CommAPI_ReceiveString($hFile, 5000)
	If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)

	_CommAPI_ClosePort($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)

	Return $sResult
EndFunc

INI file

Func Example()
	Local Const $sFileINI = @ScriptDir & "\Example.ini"

	Local $sMode = _CommAPI_CreateModeString( _
		IniRead($sFileINI, "COM", "SerialPort", 1), _
		IniRead($sFileINI, "COM", "BaudRate", 9600), _
		IniRead($sFileINI, "COM", "Parity", 0), _
		IniRead($sFileINI, "COM", "ByteSize", 8), _
		IniRead($sFileINI, "COM", "StopBits", 1), _
		IniRead($sFileINI, "COM", "XON", 0), _
		IniRead($sFileINI, "COM", "DSR", 0), _
		IniRead($sFileINI, "COM", "CTS", 1), _
		IniRead($sFileINI, "COM", "DTR", 1), _
		IniRead($sFileINI, "COM", "RTS", 1), _
		IniRead($sFileINI, "COM", "IDSR", 0))
	If @error Then Return SetError(@error, @ScriptLineNumber)

	Local $hFile = _CommAPI_OpenPort($sMode)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_ClearCommError($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_PurgeComm($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_TransmitString($hFile, IniRead($sFileINI, "COM", "Command", "Command" & @CRLF))
	If @error Then Return SetError(@error, @ScriptLineNumber)

	Local $sResult = _CommAPI_ReceiveString($hFile, IniRead($sFileINI, "Timeout", "IDSR", 5000))
	If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)

	_CommAPI_ClosePort($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)

	Return $sResult
EndFunc

Command Line

Func Example()
	If $CmdLine[0] <> 2 Then
		MsgBox(32, "Syntax", @ScriptName & ' "ModeString" "Command"')
		Exit
	EndIf

	Local $hFile = _CommAPI_OpenPort($CmdLine[1])
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_ClearCommError($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_PurgeComm($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_TransmitString($hFile, $CmdLine[2])
	If @error Then Return SetError(@error, @ScriptLineNumber)

	Local $sResult = _CommAPI_ReceiveString($hFile, 5000)
	If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)

	_CommAPI_ClosePort($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)

	Return $sResult
EndFunc

@echo off
cls
chcp 1252>nul
cd /d "%~dp0"
start Example.exe "COM1: BAUD=9600 PARITY=N DATA=8 STOP=1 XON=OFF ODSR=OFF OCTS=ON DTR=ON RTS=ON IDSR=OFF" "Command"

Separator

Func Example()
	Local $hFile = _CommAPI_OpenCOMPort(1, 9600, 0, 8, 1)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	Local $sResult = ""
	While True
		$sResult = _CommAPI_ReceiveString($hFile, 5000, 0, "<CR>")
		If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)
		MsgBox(64, "Line", $sResult)
	WEnd

	_CommAPI_ClosePort($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)

	Return $sResult
EndFunc

Slow Devices

For some slow devices the default timeout is too small of one millisecond.

Func Example()
	Local $hFile = _CommAPI_OpenCOMPort(1, 9600, 0, 8, 1)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	_CommAPI_ChangeCommTimeoutsElement($hFile, "ReadTotalTimeoutMultiplier", 100)
	If @error Then Return SetError(@error, @ScriptLineNumber)

	Local $sResult = _CommAPI_ReceiveString($hFile, 5000)
	If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)

	_CommAPI_ClosePort($hFile)
	If @error Then Return SetError(@error, @ScriptLineNumber, $sResult)

	Return $sResult
EndFunc