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This function decodes the NMEA position reports (e.g. type 1,2,3) from a ships AIS system and returns a 2D array with labels. ;~ nmea #include<array.au3> #include<file.au3> $sData = "100NtTwP00JVkTPFit5irww@2>`<" _ArrayDisplay(_NMEA_Position_Decoder($sData) , $sData) Func _NMEA_Position_Decoder($sEncString) $aAsc = StringToASCIIArray($sData) ; any ASCII over 119 is invalid , ascii 64-87 and 88-95 are not used for $i = 0 to ubound($aAsc) - 1 If $aAsc[$i] < 48 Then msgbox(0, $aAsc[$i] , $aAsc[$i] & " asc less than 48" & @LF & chrw($aAsc[$i]) & " is not a valid char" ) exit EndIF If $aAsc[$i] > 88 And $aAsc[$i] < 95 Then msgbox(0, $aAsc[$i] , $aAsc[$i] & " asc in invalid range 88-95") exit EndIF If $aAsc[$i] > 119 Then msgbox(0, $aAsc[$i] , $aAsc[$i] & " asc above 119") exit EndIF next ;~ _ArrayDisplay($aAsc , 'ASCII values') ;check ASCII conversion ;subtract 48 from each for $i = 0 to ubound($aAsc) - 1 $aAsc[$i] = number($aAsc[$i] - 48) $aAsc[$i] = $aAsc[$i] > 40 ? $aAsc[$i] - 8 : $aAsc[$i] ; if still over 40 subtract 8 Next ;~ _ArrayDisplay($aAsc, 'armored payload') ;check armored payload for $i = 0 to UBound($aAsc) - 1 If $aAsc[$i] = "0" Then $aAsc[$i] = "000000" If $aAsc[$i] = "1" Then $aAsc[$i] = "000001" If $aAsc[$i] = "2" Then $aAsc[$i] = "000010" If $aAsc[$i] = "3" Then $aAsc[$i] = "000011" If $aAsc[$i] = "4" Then $aAsc[$i] = "000100" If $aAsc[$i] = "5" Then $aAsc[$i] = "000101" If $aAsc[$i] = "6" Then $aAsc[$i] = "000110" If $aAsc[$i] = "7" Then $aAsc[$i] = "000111" If $aAsc[$i] = "8" Then $aAsc[$i] = "001000" If $aAsc[$i] = "9" Then $aAsc[$i] = "001001" If $aAsc[$i] = "10" Then $aAsc[$i] = "001010" If $aAsc[$i] = "11" Then $aAsc[$i] = "001011" If $aAsc[$i] = "12" Then $aAsc[$i] = "001100" If $aAsc[$i] = "13" Then $aAsc[$i] = "001101" If $aAsc[$i] = "14" Then $aAsc[$i] = "001110" If $aAsc[$i] = "15" Then $aAsc[$i] = "001111" If $aAsc[$i] = "16" Then $aAsc[$i] = "010000" If $aAsc[$i] = "17" Then $aAsc[$i] = "010001" If $aAsc[$i] = "18" Then $aAsc[$i] = "010010" If $aAsc[$i] = "19" Then $aAsc[$i] = "010011" If $aAsc[$i] = "20" Then $aAsc[$i] = "010100" If $aAsc[$i] = "21" Then $aAsc[$i] = "010101" If $aAsc[$i] = "22" Then $aAsc[$i] = "010110" If $aAsc[$i] = "23" Then $aAsc[$i] = "010111" If $aAsc[$i] = "24" Then $aAsc[$i] = "011000" If $aAsc[$i] = "25" Then $aAsc[$i] = "011001" If $aAsc[$i] = "26" Then $aAsc[$i] = "011010" If $aAsc[$i] = "27" Then $aAsc[$i] = "011011" If $aAsc[$i] = "28" Then $aAsc[$i] = "011100" If $aAsc[$i] = "29" Then $aAsc[$i] = "011101" If $aAsc[$i] = "30" Then $aAsc[$i] = "011110" If $aAsc[$i] = "31" Then $aAsc[$i] = "011111" If $aAsc[$i] = "32" Then $aAsc[$i] = "100000" If $aAsc[$i] = "33" Then $aAsc[$i] = "100001" If $aAsc[$i] = "34" Then $aAsc[$i] = "100010" If $aAsc[$i] = "35" Then $aAsc[$i] = "100011" If $aAsc[$i] = "36" Then $aAsc[$i] = "100100" If $aAsc[$i] = "37" Then $aAsc[$i] = "100101" If $aAsc[$i] = "38" Then $aAsc[$i] = "100110" If $aAsc[$i] = "39" Then $aAsc[$i] = "100111" If $aAsc[$i] = "40" Then $aAsc[$i] = "101000" If $aAsc[$i] = "41" Then $aAsc[$i] = "101001" If $aAsc[$i] = "42" Then $aAsc[$i] = "101010" If $aAsc[$i] = "43" Then $aAsc[$i] = "101011" If $aAsc[$i] = "44" Then $aAsc[$i] = "101100" If $aAsc[$i] = "45" Then $aAsc[$i] = "101101" If $aAsc[$i] = "46" Then $aAsc[$i] = "101110" If $aAsc[$i] = "47" Then $aAsc[$i] = "101111" If $aAsc[$i] = "48" Then $aAsc[$i] = "110000" If $aAsc[$i] = "49" Then $aAsc[$i] = "110001" If $aAsc[$i] = "50" Then $aAsc[$i] = "110010" If $aAsc[$i] = "51" Then $aAsc[$i] = "110011" If $aAsc[$i] = "52" Then $aAsc[$i] = "110100" If $aAsc[$i] = "53" Then $aAsc[$i] = "110101" If $aAsc[$i] = "54" Then $aAsc[$i] = "110110" If $aAsc[$i] = "55" Then $aAsc[$i] = "110111" If $aAsc[$i] = "56" Then $aAsc[$i] = "111000" If $aAsc[$i] = "57" Then $aAsc[$i] = "111001" If $aAsc[$i] = "58" Then $aAsc[$i] = "111010" If $aAsc[$i] = "59" Then $aAsc[$i] = "111001" If $aAsc[$i] = "60" Then $aAsc[$i] = "111100" If $aAsc[$i] = "61" Then $aAsc[$i] = "111101" If $aAsc[$i] = "62" Then $aAsc[$i] = "111110" If $aAsc[$i] = "63" Then $aAsc[$i] = "111111" next ;~ _ArrayDisplay($aAsc , 'bitstream') ;check bit stream $sBitStream = _ArrayToString($aAsc , "") $sMsgType = stringleft($sBitStream , 6) $sRptIndicator = stringmid($sBitStream , 7 , 2) $sMMSI = StringMid($sBitStream , 9 , 30) $sNavStatus = StringMid($sBitStream , 39 , 4) $sRateOfTurn = StringMid($sBitStream , 43 , 8) $sSpeedOverGrnd = StringMid($sBitStream , 51 , 10) $sPositionAccuracy = StringMid($sBitStream , 61 , 1) $slongitude = StringMid($sBitStream , 62 , 28) $slatitude = StringMid($sBitStream , 90 , 27) $sCourseOverGround = StringMid($sBitStream , 117 , 12) $sHeading = StringMid($sBitStream , 129 , 9) $sTimeStamp = StringMid($sBitStream , 138 , 6) $sManeuverIndicator = StringMid($sBitStream , 144 , 2) $sSpare = StringMid($sBitStream , 146 , 3) ;unused $sRAIMflag = StringMid($sBitStream , 149 , 1) $sRadioStatus = StringMid($sBitStream , 150 , 19) ;ending at 168 (or 28 blocks of 6) ;~ local $aBitStream[1][2] = [["message" , $sMsgType]] local $aBitStream[16][2] = [["msg_type" , _BinaryToDec($sMsgType)] , ["Repeat Ind" , _BinaryToDec($sRptIndicator)] , ["MMSI" , _BinaryToDec($sMMSI)] , ["Nav Status" , _BinaryToDec($sNavStatus)] , ["Turn Rate" , _BinaryToDec($sRateOfTurn) / 10] , _ ["Speed" , _BinaryToDec($sSpeedOverGrnd) / 10] , ["Accuracy" , _BinaryToDec($sPositionAccuracy)] , ["longitude" , $slongitude] , ["latitude" , $slatitude], ["Course" , _BinaryToDec($sCourseOverGround) / 10] , ["Heading" , _BinaryToDec($sHeading)] , ["TimeStamp" , _BinaryToDec($sTimeStamp)] , _ ["Maneuver Ind" , _BinaryToDec($sManeuverIndicator)] , ["Spare" , $sSpare] , ["RAIM flag" , _BinaryToDec($sRAIMflag)] , ["Radio Status" , _BinaryToDec($sRadioStatus)]] Return $aBitStream EndFunc ;NMEA Position Decoder ;~ ;-------------Binary To Dec----------------- Func _BinaryToDec($strBin) Local $Return Local $lngResult Local $intIndex If StringRegExp($strBin,'[0-1]') then $lngResult = 0 For $intIndex = StringLen($strBin) to 1 step -1 $strDigit = StringMid($strBin, $intIndex, 1) Select case $strDigit="0" ; do nothing case $strDigit="1" $lngResult = $lngResult + (2 ^ (StringLen($strBin)-$intIndex)) case else ; invalid binary digit, so the whole thing is invalid $lngResult = 0 $intIndex = 0 ; stop the loop EndSelect Next $Return = $lngResult Return $Return Else MsgBox(0,"Error","Wrong input, try again ...") Return EndIf EndFunc