Bitwise operators won't translate from JavaScript to PHP - php

I'm trying to translate this segment of code which makes use of bitwise operators in a loop, from JavaScript to PHP. Here is the JavaScript code:
for( var k = 0, iTop = str.length; k < iTop; k++ )
{
crc = (crc >> 8) ^ ("0x" + table.substr(((crc ^ str.charCodeAt(k) ) & 0x000000FF) * 9, 8));
document.write(crc);
}
Here is the same code translated into PHP
for($k = 0, $iTop = strlen($str); $k < $iTop; $k++ )
{
$crc = ($crc >> 8) ^ ("0x" . substr($table, (($crc ^ ord($str[$k]) ) & 0x000000FF) * 9, 8));
echo $crc;
}
These two segments give different values for the crc variable. All the variables going into both of them are identical.
Am I making a silly error, or will this code not translate because of some difficulty with translating bitwise operators?
Here is the complete code for both:
Javascript:
<html><head><meta http-equiv="Pragma" content="no-cache"/>
<meta http-equiv="Expires" content="-1"/>
<meta http-equiv="CacheControl" content="no-cache"/>
<script type="text/javascript">function test(){var table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
var c = 1750271245;
var slt = "2qGU4Lt1";
var s1 = 'v';
var s2 = 'z';
var n = 4;
var start = s1.charCodeAt(0);
var end = s2.charCodeAt(0);
var arr = new Array(n);
var m = Math.pow(((end - start) + 1),n);
for (var i=0; i<n; i++)
arr[i] = s1;
for (var i=0; i<m-1; i++){
for(var j=n-1; j>=0;--j) {
var t = arr[j].charCodeAt(0);
t++; arr[j] = String.fromCharCode(t);
if (arr[j].charCodeAt(0)<=end) {
break;
} else {
arr[j] = s1 ;
}
}
var chlg = arr.join(""); var str = chlg + slt;
var crc = 0;
var crc = crc ^ (-1);
for( var k = 0, iTop = str.length; k < iTop; k++ )
{
document.write((((crc ^ str.charCodeAt(k) ) & 0x000000FF) * 9) + "\n");
crc = (crc >> 8) ^ ("0x" + table.substr(((crc ^ str.charCodeAt(k) ) & 0x000000FF) * 9, 8));
}
crc = crc ^ (-1);
crc = Math.abs(crc);
if (crc == parseInt(c)){
break;
}
}
document.cookie ="TS884e96_75=" + "8643a82fd76d477a904aa3267724056d:" + chlg + ":" + slt + ":" + crc + ";Max-Age=3600;path=/";}</script></head><body onload="test()">
</body></html>
PHP
<?php
ini_set("display_errors","1");
$table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
$c = 1750271245; //we'd get this from reading the script
$slt = "2qGU4Lt1"; //we'd get this from reading the script
$s1 = 'v'; //we'd get this from reading the script
$s2 = 'z'; //we'd get this from reading the script
$n = 4; //we'd get this from reading the script, just to be safe
$start = ord($s1);
$end = ord($s2);
$arr = array();
$m = pow(($end - $start + 1 ), $n);
for ($i=0; $i<$n; $i++)
{
$arr[$i] = $s1;
}
for ($i=0; $i<$m-1; $i++)
{
for ($j = $n-1; $j>=0; $j--)
{
$t = ord($arr[$j]);
$t++;
$arr[$j] = chr($t);
if (ord($arr[$j]) <= $end)
{
break;
}
else
{
$arr[$j] = $s1;
}
}
$chlg = implode('', $arr);
$str = $chlg . $slt;
$crc = 0;
$crc = $crc ^ (-1);
//ord($str[$k]) Is correct
//
for($k = 0, $iTop = strlen($str); $k < $iTop; $k++ )
{
$crc = ($crc >> 8) ^ ("0x" . substr($table, (($crc ^ ord($str[$k]) ) & 0x000000FF) * 9, 8));
}
$crc = $crc ^ (-1);
$crc = abs($crc);
if ($crc == intval($c))
{
break;
}
}
echo $chlg;
?>
UPDATE: It's definitely a 32 bit issue. I know because echo (int) -1 ^ (int) 2489596804; gives -2489596805 instead of 1805370491. What should I do?
GMP CODE:
for($k = 0, $iTop = strlen($str); $k < $iTop; $k++ )
{
$crc = gmp_xor(
(gmp_intval($crc) >> 8),
hexdec(substr(
$table,
gmp_intval(gmp_mul(
gmp_and(gmp_xor($crc, ord($str[$k])), 0x000000FF),
9)),
8))
); //we use gmp because we're on 32 bit and bitwise operator cant work for that.
echo gmp_strval($crc) . "\n";
}


The "0x" trick won't work in PHP. While PHP interprets an "0x1234" string as number in some contexts, for binary arithmetic with & 0x00FF it won't work.
Instead try hexdec() around the substr(). It might however fail for too big values (which PHPs hexdec returns as float).


If the raw PHP hex notation works, then try using this converted list:
$table = array(
0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA, 0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3, 0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988, 0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91, 0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE, 0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7, 0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC, 0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5, 0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172, 0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B, 0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940, 0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59, 0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116, 0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F, 0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924, 0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D, 0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A, 0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433, 0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818, 0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01, 0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E, 0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457, 0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C, 0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65, 0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2, 0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB, 0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0, 0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9, 0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086, 0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F, 0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4, 0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD, 0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A, 0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683, 0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8, 0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1, 0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE, 0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7, 0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC, 0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5, 0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252, 0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B, 0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60, 0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79, 0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236, 0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F, 0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04, 0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D, 0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A, 0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713, 0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38, 0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21, 0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E, 0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777, 0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C, 0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45, 0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2, 0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB, 0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0, 0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9, 0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6, 0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF, 0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94, 0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
);
This simplifies the code to:
$crc = ($crc >> 8) ^ $table[($crc ^ ord($str[$k])) & 0x000000FF];
Again I'm not sure it works with PHP on a 32 bit machine.


The problem is what you want to do with this code.
If you want to parse correct cookie, it is better to get regex for value
var c = '([0-9]*)';
.. than calculate this. In the end, it is try equal to this value.

Related

How to save JSON Nested value using PHP as txt.file or Mysql database

I have a nested JSON object and i want to save the values into a txt file.
This is the nested Json object
"objectJSON":{
"alt":"136.22",
"lat":"46.7484",
"lng":"33.0685"
}
I use the following PHP code to save the values into a txt.file
<?php
header("Content-type: application/json");
$json = file_get_contents("php://input");
$obj = json_decode($json);
$decoded = base64_decode(json_encode($obj->data));
$encoded = json_encode($obj->objectJSON);
$fp = #fopen("TMP.txt", "a"); //Open and write into TMP.txt
fwrite($fp, $encoded);
fwrite($fp,"\r\n");
fclose($fp);
?>
And here are the values into the TMP.txt file
"{\"alt\":136.22,\"lat\":46.7484,\"lng\":33.0685}"
And here is the problem:
What do I have to change/add to save only the "alt" value in the TMP.txt file?
HERE ARE MORE INFORMATION ABOUT MY PROJECT.
I receive the data via a lora node to a lora gateway which send them to my lora server. Here is a part from the lora node code that has been uploaded on it:
void GPSWrite()
{
/*Convert GPS data to format*/
datastring1 +=dtostrf(flat, 0, 6, gps_lat);
datastring2 +=dtostrf(flon, 0, 6, gps_lon);
//datastring3 +=dtostrf(falt, 0, 2, gps_alt);
if(flon!=1000.000000)
{
strcat(gps_lon,",");
strcat(gps_lon,gps_lat);
//strcat(gps_lon,",");
//strcat(gps_lon,gps_alt);
int i = 0;
for(i = 0; i < 2; i++)
{
//datasend.toFloat();
atof(gps_lon);
//Serial.println((char*)datasend);
Serial.println("Testing converted data:");
Serial.println(gps_lon);
// atof(gps_alt);
// Serial.print(gps_alt);
}
strcpy(datasend,gps_lon); //the format of datasend is longtitude,latitude,altitude
Serial.print("########### ");
Serial.print("NO.");
Serial.print(count);
Serial.println(" ###########");
Serial.println("The longtitude and latitude are:");
Serial.print("[");
Serial.print((char*)datasend);
Serial.print("]");
Serial.print("");
/*
for(int k = 0; k < 20;k++)
{
Serial.print("[");
Serial.print(datasend[k], HEX);
Serial.print("]");
}
Serial.println("");
Serial.println("");*/
count++;
}
int32_t lat = flat * 10000;
int32_t lng = flon * 10000;
datasend[0] = lng;
datasend[1] = lng >> 8;
datasend[2] = lng >> 16;
datasend[3] = lat;
datasend[4] = lat >> 8;
datasend[5] = lat >> 16;
smartdelay(1000);
}
static void smartdelay(unsigned long ms)
{
unsigned long start = millis();
do
{
while (ss.available())
{
gps.encode(ss.read());
}
} while (millis() - start < ms);
}
void loop() {
os_runloop_once();
}
The application server decodes the data with the following function:
function Decode(fPort, bytes) {
var decoded = {};
var hexString=bin2HexStr(bytes);
return rakSensorDataDecode(hexString);
}
// convert array of bytes to hex string.
// e.g: 0188053797109D5900DC140802017A0768580673256D0267011D040214AF0371FFFFFFDDFC2E
function bin2HexStr(bytesArr) {
var str = "";
for(var i=0; i<bytesArr.length; i++) {
var tmp = (bytesArr[i] & 0xff).toString(16);
if(tmp.length == 1) {
tmp = "0" + tmp;
}
str += tmp;
}
return str;
}
// convert string to short integer
function parseShort(str, base) {
var n = parseInt(str, base);
return (n << 16) >> 16;
}
// convert string to triple bytes integer
function parseTriple(str, base) {
var n = parseInt(str, base);
return (n << 8) >> 8;
}
// decode Hex sensor string data to object
function rakSensorDataDecode(hexStr) {
var str = hexStr;
var myObj = {};
while (str.length > 4) {
var flag = parseInt(str.substring(0, 4), 16);
{
myObj.lat = (bytes[3] | bytes[4]<<8 | bytes[5]<<16 | (bytes[5] & 0x80 ? 0xFF<<24 : 0)) / 10000;
myObj.lng = (bytes[0] | bytes[1]<<8 | bytes[2]<<16 | (bytes[2] & 0x80 ? 0xFF<<24 : 0)) / 10000;
myObj.alt = ((bytes[6] << 8) + bytes[7])/100;
str = str.substring(22);
}
}
return myObj;
}
so I get through my application server the following results:
received data
Then I use the php script to save data on txt, file. As I have told you, the problem is that I can save all data but can't save for example only the altitude.

The only thing you have to do is decode and then encode and write the proper one:
$json = file_get_contents("php://input");
$obj = json_decode($json);
file_put_contents("TMP.txt", json_encode($obj->objectJSON->alt));
If you want to append then:
file_put_contents("TMP.txt",
file_get_contents("TMP.txt") . json_encode($obj->objectJSON->alt));
But that won't be valid JSON in the file.

You are using the encoded data, instead use decoded data if you want to access the 'alt' attribute, here is an example :
<?php
$obj = (object) [
"objectJSON" => [
'alt' => '136.22',
'lat' => '46.7484',
'lng' => '33.0685'
]
];
$encoded = json_encode($obj->objectJSON);
$decoded = json_decode($encoded);
$fp = #fopen("TMP.txt", "a"); //Open and write into TMP.txt
fwrite($fp, $decoded->alt);
fwrite($fp,"\r\n");
fclose($fp);
?>

You just need to extract the value from the object:
$fp = #fopen("TMP.txt", "a"); //Open and write into TMP.txt
fwrite($fp, $decoded->alt);
// ^^^^^^^
fwrite($fp,"\r\n");
fclose($fp);

Finally, I can save my data in a txt file and I can insert my data into a MySQL database at the same time. Thank you all for your help. Here is the PHP script
<?php
header("Content-type: application/json");
$json = file_get_contents("php://input");
$obj = json_decode($json);
$decoded = base64_decode(json_encode($obj->data));
$fp = #fopen("TMP.txt", "a"); //Open and write into TMP.txt
fwrite($fp,$decoded);
fwrite($fp,"\r\n");
fclose($fp);
$server = "#######";
$username = "#######";
$password = "#######";
$DB = "#######";
$conn = new mysqli($server, $username, $password, $DB);
if ($conn->connect_error)
{
die("Connection failed: " . $conn->connect_error);
}
$insert = "INSERT INTO gpssensor(longitude, latitude) VALUES ($decoded)";
$conn->query($insert);
$conn->close();
?>

Calculate CRC16 X25 in php

I need help in calculating CRC X25 variation, i have a Java tool and also an online tool that give the correct conversion, but i haven't been able to reproduce it myself.
Online Tool
Github for online tool
String: 40402900033231334C323031373030313839360000000000009001FFFFFFFF0000D656B759
Input type: Hex -> Calc CRC16
Result: CRC-16/X-25
0x6C49 <-- this is the value im trying to get in php from that string above.
My Php code so far
private static $CRC16_Table = array
(0x0000, 0x1189, 0x2312, 0x329B, 0x4624, 0x57AD,
0x6536, 0x74BF, 0x8C48, 0x9DC1, 0xAF5A, 0xBED3,
0xCA6C, 0xDBE5, 0xE97E, 0xF8F7, 0x1081, 0x0108,
0x3393, 0x221A, 0x56A5, 0x472C, 0x75B7, 0x643E,
0x9CC9, 0x8D40, 0xBFDB, 0xAE52, 0xDAED, 0xCB64,
0xF9FF, 0xE876, 0x2102, 0x308B, 0x0210, 0x1399,
0x6726, 0x76AF, 0x4434, 0x55BD, 0xAD4A, 0xBCC3,
0x8E58, 0x9FD1, 0xEB6E, 0xFAE7, 0xC87C, 0xD9F5,
0x3183, 0x200A, 0x1291, 0x0318, 0x77A7, 0x662E,
0x54B5, 0x453C, 0xBDCB, 0xAC42, 0x9ED9, 0x8F50,
0xFBEF, 0xEA66, 0xD8FD, 0xC974, 0x4204, 0x538D,
0x6116, 0x709F, 0x0420, 0x15A9, 0x2732, 0x36BB,
0xCE4C, 0xDFC5, 0xED5E, 0xFCD7, 0x8868, 0x99E1,
0xAB7A, 0xBAF3, 0x5285, 0x430C, 0x7197, 0x601E,
0x14A1, 0x0528, 0x37B3, 0x263A, 0xDECD, 0xCF44,
0xFDDF, 0xEC56, 0x98E9, 0x8960, 0xBBFB, 0xAA72,
0x6306, 0x728F, 0x4014, 0x519D, 0x2522, 0x34AB,
0x0630, 0x17B9, 0xEF4E, 0xFEC7, 0xCC5C, 0xDDD5,
0xA96A, 0xB8E3, 0x8A78, 0x9BF1, 0x7387, 0x620E,
0x5095, 0x411C, 0x35A3, 0x242A, 0x16B1, 0x0738,
0xFFCF, 0xEE46, 0xDCDD, 0xCD54, 0xB9EB, 0xA862,
0x9AF9, 0x8B70, 0x8408, 0x9581, 0xA71A, 0xB693,
0xC22C, 0xD3A5, 0xE13E, 0xF0B7, 0x0840, 0x19C9,
0x2B52, 0x3ADB, 0x4E64, 0x5FED, 0x6D76, 0x7CFF,
0x9489, 0x8500, 0xB79B, 0xA612, 0xD2AD, 0xC324,
0xF1BF, 0xE036, 0x18C1, 0x0948, 0x3BD3, 0x2A5A,
0x5EE5, 0x4F6C, 0x7DF7, 0x6C7E, 0xA50A, 0xB483,
0x8618, 0x9791, 0xE32E, 0xF2A7, 0xC03C, 0xD1B5,
0x2942, 0x38CB, 0x0A50, 0x1BD9, 0x6F66, 0x7EEF,
0x4C74, 0x5DFD, 0xB58B, 0xA402, 0x9699, 0x8710,
0xF3AF, 0xE226, 0xD0BD, 0xC134, 0x39C3, 0x284A,
0x1AD1, 0x0B58, 0x7FE7, 0x6E6E, 0x5CF5, 0x4D7C,
0xC60C, 0xD785, 0xE51E, 0xF497, 0x8028, 0x91A1,
0xA33A, 0xB2B3, 0x4A44, 0x5BCD, 0x6956, 0x78DF,
0x0C60, 0x1DE9, 0x2F72, 0x3EFB, 0xD68D, 0xC704,
0xF59F, 0xE416, 0x90A9, 0x8120, 0xB3BB, 0xA232,
0x5AC5, 0x4B4C, 0x79D7, 0x685E, 0x1CE1, 0x0D68,
0x3FF3, 0x2E7A, 0xE70E, 0xF687, 0xC41C, 0xD595,
0xA12A, 0xB0A3, 0x8238, 0x93B1, 0x6B46, 0x7ACF,
0x4854, 0x59DD, 0x2D62, 0x3CEB, 0x0E70, 0x1FF9,
0xF78F, 0xE606, 0xD49D, 0xC514, 0xB1AB, 0xA022,
0x92B9, 0x8330, 0x7BC7, 0x6A4E, 0x58D5, 0x495C,
0x3DE3, 0x2C6A, 0x1EF1, 0x0F78,
);
public static function calculate($buffer) {
$length = strlen($buffer);
$crc = 0;
$i = 0;
while ($length--) {
$crc = (( $crc >> 8) & 0xff) ^ (self::$CRC16_Table[(ord($buffer[$i++]) ^ $crc) & 0xFF]);
}
return (($crc & 0xFFFF) ^ 0x8000) - 0x8000;
}
public static function ComputeCrc($data) {
$crc = 0xFFFF;
foreach ($data as $d) {
$crc = self::$CRC16_Table[($d ^ $crc) & 0xFF] ^ ($crc >> 8 & 0xFF);
}
$crc = $crc ^ 0xFFFF;
$crc = $crc & 0xFFFF;
return $crc;
}
This gives me results as follows
ComputeCrc(str_split("40402900033231334C323031373030313839360000000000009001FFFFFFFF0000D656B759", 2));
Result = ec71 <-- decHex result
calculate("40402900033231334C323031373030313839360000000000009001FFFFFFFF0000D656B759");
Result = 48d7; <-- decHex result
Any help will be very appreciated

Solved it applying hexdec before the calculation, may be useful in the future.
public static function ComputeCrc($data) {
$crc = 0xFFFF;
foreach ($data as $d) {
$d = hexdec($d); <-- This did the trick
$crc = self::$CRC16_Table[($d ^ $crc) & 0xFF] ^ ($crc >> 8 & 0xFF);
}
$crc = $crc ^ 0xFFFF;
$crc = $crc & 0xFFFF;
return $crc;
}

polygon matrix calculation for viscosity matrix

I am writing a program which needs different value of gas viscosity at different temperature for respective gases. Data which i have is given below. I am new in programming in php . can anyone please give me the logic behind it. so that i can get viscosity at any required tempertaure through the program. thanks
Data for viscosity calculation (dyn. visc. [Ns/m² = kg/ms]; Source: VDI Wärmeatlas
Temp. [°C] 0 100 200 300 400 500
CO2 1,37E-05 1,82E-05 2,22E-05 2,59E-05 2,93E-05 3,24E-05
O2 1,92E-05 2,43E-05 2,88E-05 3,29E-05 3,67E-05 4,03E-05
H2O 9,00E-06 1,25E-05 1,61E-05 1,97E-05 2,33E-05 2,69E-05
N2 1,66E-05 2,09E-05 2,47E-05 2,82E-05 3,14E-05 3,42E-05

You can easily fit your data in Excel. Here's a plot that shows the result, along with the 2nd order polynomial:

Finally I got the right answer. In case if anyone need it, I am posting it out here:
class baseViscosityCalc {
public $arViscosity = array(
array(0, 1.37e-05, 1.92e-05, 9.00e-06, 1.66e-05),
array(100, 1.82e-05, 2.43e-05, 1.25e-05, 2.09e-05),
array(200, 2.22e-05, 2.88e-05, 1.61e-05, 2.47e-05),
array(300, 2.59e-05, 3.29e-05, 1.97e-05, 2.82e-05),
array(400, 2.93e-05, 3.67e-05, 2.33e-05, 3.14e-05),
array(500, 3.24e-05, 4.03e-05, 2.69e-05, 3.42e-05)
);
public function getViscosityData($DCat) {
$arValue = array(
'Temperature' => 0.0,
'CO2' => 0.0,
'O2' => 0.0,
'H2O' => 0.0,
'N2' => 0.0
);
for ($i = 0; $i < count($this->arViscosity); $i++) {
$arValue['Temperature'] = $DCat;
if ($DCat < $this->arViscosity[0][0]) {
$arValue['CO2'] = $this->arViscosity[0][1];
$arValue['O2'] = $this->arViscosity[0][2];
$arValue['H2O'] = $this->arViscosity[0][3];
$arValue['N2'] = $this->arViscosity[0][4];
break;
}
if ($DCat > $this->arViscosity[count($this->arViscosity) - 1][0]) {
$arValue['CO2'] = $this->arViscosity[count($this->arViscosity) - 1][1];
$arValue['O2'] = $this->arViscosity[count($this->arViscosity) - 1][2];
$arValue['H2O'] = $this->arViscosity[count($this->arViscosity) - 1][3];
$arValue['N2'] = $this->arViscosity[count($this->arViscosity) - 1][4];
breaK;
}
if ($DCat > $this->arViscosity[$i][0] && $DCat < $this->arViscosity[$i + 1][0]) {
$factor = ($DCat - $this->arViscosity[$i][0]) / ($this->arViscosity[$i + 1][0] - $this->arViscosity[$i][0]);
$arValue['CO2'] = $factor * ($this->arViscosity[$i + 1][1] - $this->arViscosity[$i][1]) + $this->arViscosity[$i][1];
$arValue['O2'] = $factor * ($this->arViscosity[$i + 1][2] - $this->arViscosity[$i][2]) + $this->arViscosity[$i][2];
$arValue['H2O'] = $factor * ($this->arViscosity[$i + 1][3] - $this->arViscosity[$i][3]) + $this->arViscosity[$i][3];
$arValue['N2'] = $factor * ($this->arViscosity[$i + 1][4] - $this->arViscosity[$i][4]) + $this->arViscosity[$i][4];
break;
}
}
return $arValue;
}
}

CRC-CCITT to CRC16 Modbus implementation

I am having a lot of trouble on generating a modbus CRC16 code using PHP. I have found a lot of different codes over the internet but i have tried them and for some reason i didnt get right results. I have found a PHP code for generating CRC16-CCITT. I have chenge the look up table to the modbus CRC corresponding table but the result is still not the right one.
The code is bellow. What do i need to do more in order to transform a CRC16-CCITT code into CRC16-MODBUS code.
<?php
/*************************************************************************
* phpCrc16 v1.1 -- CRC16/CCITT implementation
*
* By Matteo Beccati <matteo#beccati.com>
*
* Original code by:
* Ashley Roll
* Digital Nemesis Pty Ltd
* www.digitalnemesis.com
* ash#digitalnemesis.com
*
* Test Vector: "123456789" (character string, no quotes)
* Generated CRC: 0x29B1
*
*************************************************************************/
/*
* Returns CRC16 of a string as int value
*/
function CRC16($str)
{
static $CRC16_Lookup = array(
0X0000, 0XC0C1, 0XC181, 0X0140, 0XC301, 0X03C0, 0X0280, 0XC241,
0XC601, 0X06C0, 0X0780, 0XC741, 0X0500, 0XC5C1, 0XC481, 0X0440,
0XCC01, 0X0CC0, 0X0D80, 0XCD41, 0X0F00, 0XCFC1, 0XCE81, 0X0E40,
0X0A00, 0XCAC1, 0XCB81, 0X0B40, 0XC901, 0X09C0, 0X0880, 0XC841,
0XD801, 0X18C0, 0X1980, 0XD941, 0X1B00, 0XDBC1, 0XDA81, 0X1A40,
0X1E00, 0XDEC1, 0XDF81, 0X1F40, 0XDD01, 0X1DC0, 0X1C80, 0XDC41,
0X1400, 0XD4C1, 0XD581, 0X1540, 0XD701, 0X17C0, 0X1680, 0XD641,
0XD201, 0X12C0, 0X1380, 0XD341, 0X1100, 0XD1C1, 0XD081, 0X1040,
0XF001, 0X30C0, 0X3180, 0XF141, 0X3300, 0XF3C1, 0XF281, 0X3240,
0X3600, 0XF6C1, 0XF781, 0X3740, 0XF501, 0X35C0, 0X3480, 0XF441,
0X3C00, 0XFCC1, 0XFD81, 0X3D40, 0XFF01, 0X3FC0, 0X3E80, 0XFE41,
0XFA01, 0X3AC0, 0X3B80, 0XFB41, 0X3900, 0XF9C1, 0XF881, 0X3840,
0X2800, 0XE8C1, 0XE981, 0X2940, 0XEB01, 0X2BC0, 0X2A80, 0XEA41,
0XEE01, 0X2EC0, 0X2F80, 0XEF41, 0X2D00, 0XEDC1, 0XEC81, 0X2C40,
0XE401, 0X24C0, 0X2580, 0XE541, 0X2700, 0XE7C1, 0XE681, 0X2640,
0X2200, 0XE2C1, 0XE381, 0X2340, 0XE101, 0X21C0, 0X2080, 0XE041,
0XA001, 0X60C0, 0X6180, 0XA141, 0X6300, 0XA3C1, 0XA281, 0X6240,
0X6600, 0XA6C1, 0XA781, 0X6740, 0XA501, 0X65C0, 0X6480, 0XA441,
0X6C00, 0XACC1, 0XAD81, 0X6D40, 0XAF01, 0X6FC0, 0X6E80, 0XAE41,
0XAA01, 0X6AC0, 0X6B80, 0XAB41, 0X6900, 0XA9C1, 0XA881, 0X6840,
0X7800, 0XB8C1, 0XB981, 0X7940, 0XBB01, 0X7BC0, 0X7A80, 0XBA41,
0XBE01, 0X7EC0, 0X7F80, 0XBF41, 0X7D00, 0XBDC1, 0XBC81, 0X7C40,
0XB401, 0X74C0, 0X7580, 0XB541, 0X7700, 0XB7C1, 0XB681, 0X7640,
0X7200, 0XB2C1, 0XB381, 0X7340, 0XB101, 0X71C0, 0X7080, 0XB041,
0X5000, 0X90C1, 0X9181, 0X5140, 0X9301, 0X53C0, 0X5280, 0X9241,
0X9601, 0X56C0, 0X5780, 0X9741, 0X5500, 0X95C1, 0X9481, 0X5440,
0X9C01, 0X5CC0, 0X5D80, 0X9D41, 0X5F00, 0X9FC1, 0X9E81, 0X5E40,
0X5A00, 0X9AC1, 0X9B81, 0X5B40, 0X9901, 0X59C0, 0X5880, 0X9841,
0X8801, 0X48C0, 0X4980, 0X8941, 0X4B00, 0X8BC1, 0X8A81, 0X4A40,
0X4E00, 0X8EC1, 0X8F81, 0X4F40, 0X8D01, 0X4DC0, 0X4C80, 0X8C41,
0X4400, 0X84C1, 0X8581, 0X4540, 0X8701, 0X47C0, 0X4680, 0X8641,
0X8201, 0X42C0, 0X4380, 0X8341, 0X4100, 0X81C1, 0X8081, 0X4040
);
$crc16 = 0xFFFF; // the CRC
$len = strlen($str);
for($i = 0; $i < $len; $i++ )
{
$t = ($crc16 >> 8) ^ ord($str[$i]); // High byte Xor Message Byte to get index
$crc16 = (($crc16 << 8) & 0xffff) ^ $CRC16_Lookup[$t]; // Update the CRC from table
}
// crc16 now contains the CRC value
return $crc16;
}
/*
* Returns CRC16 of a string as hexadecimal string
*/
function CRC16HexDigest($str)
{
return sprintf('%04X', crc16($str));
}
echo CRC16HexDigest('123456789');
?>

This Pascal snippet is MODBUS RTU (ASCII is different) protocol online calculation without any table:
function mb_CalcCRC16(ptr: pointer to byte; ByteCount: byte): word;
var
crc: word;
b, i, n: byte;
begin
crc := $FFFF;
for i := 0 to ByteCount do
if i = 0 then // device id is 1st byte in message, and it is not in the buffer
b := mb_GetMessageID; // so we have to calculate it and put it as 1st crc byte
else
b := ptr^;
Inc(ptr);
endif;
crc := crc xor word(b);
for n := 1 to 8 do
if (crc and 1) = 1 then
crc := (crc shr 1) xor $A001;
else
crc := crc shr 1;
endif;
endfor;
endfor;
Return(crc);
end;
function mb_CalcCRC: word; // Calculate CRC for message in mb_pdu
begin // this message can be one that is just received, or in a reply we have just composed
Return(mb_CalcCRC16(#mb_pdu[1], mb_GetEndOfData));
end;
That's a quote from a working embedded AVR device with implemented MODBUS RTU slave protocol.

This is faster than lookup table
function crc16($data)
{
$crc = 0xFFFF;
for ($i = 0; $i < strlen($data); $i++)
{
$crc ^=ord($data[$i]);
for ($j = 8; $j !=0; $j--)
{
if (($crc & 0x0001) !=0)
{
$crc >>= 1;
$crc ^= 0xA001;
}
else
$crc >>= 1;
}
}
return $crc;
}

years after, your answers are very usefull for me. I combine your answers in a non lookup table solution:
function crc16_modbus($msg)
{
$data = pack('H*',$msg);
$crc = 0xFFFF;
for ($i = 0; $i < strlen($data); $i++)
{
$crc ^=ord($data[$i]);
for ($j = 8; $j !=0; $j--)
{
if (($crc & 0x0001) !=0)
{
$crc >>= 1;
$crc ^= 0xA001;
}
else $crc >>= 1;
}
}
return sprintf('%04X', $crc);
}
The results I am waiting for are consistent with online tools like:
lammertbies
tahapaksu

Thans for your response. I was able to perfome the Modbus crc check in PHP with the following code:
<?php
//Calcula o CRC para uma mensagem modbus
function modbus_crc($modbus_msg){
$crctab16 = [0X0000, 0XC0C1, 0XC181, 0X0140, 0XC301, 0X03C0, 0X0280, 0XC241,
0XC601, 0X06C0, 0X0780, 0XC741, 0X0500, 0XC5C1, 0XC481, 0X0440,
0XCC01, 0X0CC0, 0X0D80, 0XCD41, 0X0F00, 0XCFC1, 0XCE81, 0X0E40,
0X0A00, 0XCAC1, 0XCB81, 0X0B40, 0XC901, 0X09C0, 0X0880, 0XC841,
0XD801, 0X18C0, 0X1980, 0XD941, 0X1B00, 0XDBC1, 0XDA81, 0X1A40,
0X1E00, 0XDEC1, 0XDF81, 0X1F40, 0XDD01, 0X1DC0, 0X1C80, 0XDC41,
0X1400, 0XD4C1, 0XD581, 0X1540, 0XD701, 0X17C0, 0X1680, 0XD641,
0XD201, 0X12C0, 0X1380, 0XD341, 0X1100, 0XD1C1, 0XD081, 0X1040,
0XF001, 0X30C0, 0X3180, 0XF141, 0X3300, 0XF3C1, 0XF281, 0X3240,
0X3600, 0XF6C1, 0XF781, 0X3740, 0XF501, 0X35C0, 0X3480, 0XF441,
0X3C00, 0XFCC1, 0XFD81, 0X3D40, 0XFF01, 0X3FC0, 0X3E80, 0XFE41,
0XFA01, 0X3AC0, 0X3B80, 0XFB41, 0X3900, 0XF9C1, 0XF881, 0X3840,
0X2800, 0XE8C1, 0XE981, 0X2940, 0XEB01, 0X2BC0, 0X2A80, 0XEA41,
0XEE01, 0X2EC0, 0X2F80, 0XEF41, 0X2D00, 0XEDC1, 0XEC81, 0X2C40,
0XE401, 0X24C0, 0X2580, 0XE541, 0X2700, 0XE7C1, 0XE681, 0X2640,
0X2200, 0XE2C1, 0XE381, 0X2340, 0XE101, 0X21C0, 0X2080, 0XE041,
0XA001, 0X60C0, 0X6180, 0XA141, 0X6300, 0XA3C1, 0XA281, 0X6240,
0X6600, 0XA6C1, 0XA781, 0X6740, 0XA501, 0X65C0, 0X6480, 0XA441,
0X6C00, 0XACC1, 0XAD81, 0X6D40, 0XAF01, 0X6FC0, 0X6E80, 0XAE41,
0XAA01, 0X6AC0, 0X6B80, 0XAB41, 0X6900, 0XA9C1, 0XA881, 0X6840,
0X7800, 0XB8C1, 0XB981, 0X7940, 0XBB01, 0X7BC0, 0X7A80, 0XBA41,
0XBE01, 0X7EC0, 0X7F80, 0XBF41, 0X7D00, 0XBDC1, 0XBC81, 0X7C40,
0XB401, 0X74C0, 0X7580, 0XB541, 0X7700, 0XB7C1, 0XB681, 0X7640,
0X7200, 0XB2C1, 0XB381, 0X7340, 0XB101, 0X71C0, 0X7080, 0XB041,
0X5000, 0X90C1, 0X9181, 0X5140, 0X9301, 0X53C0, 0X5280, 0X9241,
0X9601, 0X56C0, 0X5780, 0X9741, 0X5500, 0X95C1, 0X9481, 0X5440,
0X9C01, 0X5CC0, 0X5D80, 0X9D41, 0X5F00, 0X9FC1, 0X9E81, 0X5E40,
0X5A00, 0X9AC1, 0X9B81, 0X5B40, 0X9901, 0X59C0, 0X5880, 0X9841,
0X8801, 0X48C0, 0X4980, 0X8941, 0X4B00, 0X8BC1, 0X8A81, 0X4A40,
0X4E00, 0X8EC1, 0X8F81, 0X4F40, 0X8D01, 0X4DC0, 0X4C80, 0X8C41,
0X4400, 0X84C1, 0X8581, 0X4540, 0X8701, 0X47C0, 0X4680, 0X8641,
0X8201, 0X42C0, 0X4380, 0X8341, 0X4100, 0X81C1, 0X8081, 0X4040];
$hexdata = pack('H*',$modbus_msg);
$nLength = strlen($hexdata);
$fcs = 0xFFFF;
$pos = 0;
while($nLength > 0)
{
$fcs = ($fcs >> 8) ^ $crctab16[($fcs ^ ord($hexdata[$pos])) & 0xFF];
$nLength--;
$pos++;
}
$crc_semi_inverted = sprintf('%04X', $fcs);//modbus crc invert the hight and low bit so we need to put the last two letter in the begining
$crc_modbus = substr($crc_semi_inverted,2,2).substr($crc_semi_inverted,0,2);
return $crc_modbus;
}
?>
You should enter a string with a message in hexadecimal:
$modbus_msg='01040000002';
$modbus_msg_crc=modbus_crc($modbus_msg);

This is a compact version of CRC16-ANSI (IBM) algorithm used for ModBus RTU.
function crc16_ansi($data) {
$crc = 0xFFFF;
for ($i = 0; $i < strlen($data); $i++){
$crc ^= ord($data[$i]);
for($j = 8; $j--;)
$crc = $crc & 0x0001 ? $crc = ($crc >> 1) ^ 0xA001 : $crc >> 1;
}
return $crc;
}

How to calculate crc16 in php

I need help in converting CRC code written in Ojective C to PHP. The following is the Objective C code
static UInt16 CRC16_Table[] =
{ 0x0000, 0x2110, 0x4220, 0x6330, 0x8440, 0xa550, 0xc660, 0xe770,
0x0881, 0x2991, 0x4aa1, 0x6bb1, 0x8cc1, 0xadd1, 0xcee1, 0xeff1,
0x3112, 0x1002, 0x7332, 0x5222, 0xb552, 0x9442, 0xf772, 0xd662,
0x3993, 0x1883, 0x7bb3, 0x5aa3, 0xbdd3, 0x9cc3, 0xfff3, 0xdee3,
0x6224, 0x4334, 0x2004, 0x0114, 0xe664, 0xc774, 0xa444, 0x8554,
0x6aa5, 0x4bb5, 0x2885, 0x0995, 0xeee5, 0xcff5, 0xacc5, 0x8dd5,
0x5336, 0x7226, 0x1116, 0x3006, 0xd776, 0xf666, 0x9556, 0xb446,
0x5bb7, 0x7aa7, 0x1997, 0x3887, 0xdff7, 0xfee7, 0x9dd7, 0xbcc7,
0xc448, 0xe558, 0x8668, 0xa778, 0x4008, 0x6118, 0x0228, 0x2338,
0xccc9, 0xedd9, 0x8ee9, 0xaff9, 0x4889, 0x6999, 0x0aa9, 0x2bb9,
0xf55a, 0xd44a, 0xb77a, 0x966a, 0x711a, 0x500a, 0x333a, 0x122a,
0xfddb, 0xdccb, 0xbffb, 0x9eeb, 0x799b, 0x588b, 0x3bbb, 0x1aab,
0xa66c, 0x877c, 0xe44c, 0xc55c, 0x222c, 0x033c, 0x600c, 0x411c,
0xaeed, 0x8ffd, 0xeccd, 0xcddd, 0x2aad, 0x0bbd, 0x688d, 0x499d,
0x977e, 0xb66e, 0xd55e, 0xf44e, 0x133e, 0x322e, 0x511e, 0x700e,
0x9fff, 0xbeef, 0xdddf, 0xfccf, 0x1bbf, 0x3aaf, 0x599f, 0x788f,
0x8891, 0xa981, 0xcab1, 0xeba1, 0x0cd1, 0x2dc1, 0x4ef1, 0x6fe1,
0x8010, 0xa100, 0xc230, 0xe320, 0x0450, 0x2540, 0x4670, 0x6760,
0xb983, 0x9893, 0xfba3, 0xdab3, 0x3dc3, 0x1cd3, 0x7fe3, 0x5ef3,
0xb102, 0x9012, 0xf322, 0xd232, 0x3542, 0x1452, 0x7762, 0x5672,
0xeab5, 0xcba5, 0xa895, 0x8985, 0x6ef5, 0x4fe5, 0x2cd5, 0x0dc5,
0xe234, 0xc324, 0xa014, 0x8104, 0x6674, 0x4764, 0x2454, 0x0544,
0xdba7, 0xfab7, 0x9987, 0xb897, 0x5fe7, 0x7ef7, 0x1dc7, 0x3cd7,
0xd326, 0xf236, 0x9106, 0xb016, 0x5766, 0x7676, 0x1546, 0x3456,
0x4cd9, 0x6dc9, 0x0ef9, 0x2fe9, 0xc899, 0xe989, 0x8ab9, 0xaba9,
0x4458, 0x6548, 0x0678, 0x2768, 0xc018, 0xe108, 0x8238, 0xa328,
0x7dcb, 0x5cdb, 0x3feb, 0x1efb, 0xf98b, 0xd89b, 0xbbab, 0x9abb,
0x754a, 0x545a, 0x376a, 0x167a, 0xf10a, 0xd01a, 0xb32a, 0x923a,
0x2efd, 0x0fed, 0x6cdd, 0x4dcd, 0xaabd, 0x8bad, 0xe89d, 0xc98d,
0x267c, 0x076c, 0x645c, 0x454c, 0xa23c, 0x832c, 0xe01c, 0xc10c,
0x1fef, 0x3eff, 0x5dcf, 0x7cdf, 0x9baf, 0xbabf, 0xd98f, 0xf89f,
0x176e, 0x367e, 0x554e, 0x745e, 0x932e, 0xb23e, 0xd10e, 0xf01e
};
+(SInt16) CalculateCRC16 : (Byte*)buffer : (UInt16) length
{
UInt32 crc=0;
while (length--)
crc = ((crc>>8) & 0xff) ^ *(CRC16_Table + ((*buffer++ ^ crc) & 0xff));
return((SInt16)crc);
}
and the following is the code I've written so far in php
$CRC16_Table = array
( 0x0000, 0x2110, 0x4220, 0x6330, 0x8440, 0xa550, 0xc660, 0xe770,
0x0881, 0x2991, 0x4aa1, 0x6bb1, 0x8cc1, 0xadd1, 0xcee1, 0xeff1,
0x3112, 0x1002, 0x7332, 0x5222, 0xb552, 0x9442, 0xf772, 0xd662,
0x3993, 0x1883, 0x7bb3, 0x5aa3, 0xbdd3, 0x9cc3, 0xfff3, 0xdee3,
0x6224, 0x4334, 0x2004, 0x0114, 0xe664, 0xc774, 0xa444, 0x8554,
0x6aa5, 0x4bb5, 0x2885, 0x0995, 0xeee5, 0xcff5, 0xacc5, 0x8dd5,
0x5336, 0x7226, 0x1116, 0x3006, 0xd776, 0xf666, 0x9556, 0xb446,
0x5bb7, 0x7aa7, 0x1997, 0x3887, 0xdff7, 0xfee7, 0x9dd7, 0xbcc7,
0xc448, 0xe558, 0x8668, 0xa778, 0x4008, 0x6118, 0x0228, 0x2338,
0xccc9, 0xedd9, 0x8ee9, 0xaff9, 0x4889, 0x6999, 0x0aa9, 0x2bb9,
0xf55a, 0xd44a, 0xb77a, 0x966a, 0x711a, 0x500a, 0x333a, 0x122a,
0xfddb, 0xdccb, 0xbffb, 0x9eeb, 0x799b, 0x588b, 0x3bbb, 0x1aab,
0xa66c, 0x877c, 0xe44c, 0xc55c, 0x222c, 0x033c, 0x600c, 0x411c,
0xaeed, 0x8ffd, 0xeccd, 0xcddd, 0x2aad, 0x0bbd, 0x688d, 0x499d,
0x977e, 0xb66e, 0xd55e, 0xf44e, 0x133e, 0x322e, 0x511e, 0x700e,
0x9fff, 0xbeef, 0xdddf, 0xfccf, 0x1bbf, 0x3aaf, 0x599f, 0x788f,
0x8891, 0xa981, 0xcab1, 0xeba1, 0x0cd1, 0x2dc1, 0x4ef1, 0x6fe1,
0x8010, 0xa100, 0xc230, 0xe320, 0x0450, 0x2540, 0x4670, 0x6760,
0xb983, 0x9893, 0xfba3, 0xdab3, 0x3dc3, 0x1cd3, 0x7fe3, 0x5ef3,
0xb102, 0x9012, 0xf322, 0xd232, 0x3542, 0x1452, 0x7762, 0x5672,
0xeab5, 0xcba5, 0xa895, 0x8985, 0x6ef5, 0x4fe5, 0x2cd5, 0x0dc5,
0xe234, 0xc324, 0xa014, 0x8104, 0x6674, 0x4764, 0x2454, 0x0544,
0xdba7, 0xfab7, 0x9987, 0xb897, 0x5fe7, 0x7ef7, 0x1dc7, 0x3cd7,
0xd326, 0xf236, 0x9106, 0xb016, 0x5766, 0x7676, 0x1546, 0x3456,
0x4cd9, 0x6dc9, 0x0ef9, 0x2fe9, 0xc899, 0xe989, 0x8ab9, 0xaba9,
0x4458, 0x6548, 0x0678, 0x2768, 0xc018, 0xe108, 0x8238, 0xa328,
0x7dcb, 0x5cdb, 0x3feb, 0x1efb, 0xf98b, 0xd89b, 0xbbab, 0x9abb,
0x754a, 0x545a, 0x376a, 0x167a, 0xf10a, 0xd01a, 0xb32a, 0x923a,
0x2efd, 0x0fed, 0x6cdd, 0x4dcd, 0xaabd, 0x8bad, 0xe89d, 0xc98d,
0x267c, 0x076c, 0x645c, 0x454c, 0xa23c, 0x832c, 0xe01c, 0xc10c,
0x1fef, 0x3eff, 0x5dcf, 0x7cdf, 0x9baf, 0xbabf, 0xd98f, 0xf89f,
0x176e, 0x367e, 0x554e, 0x745e, 0x932e, 0xb23e, 0xd10e, 0xf01e
);
function CalculateCRC16($strMessage)
{
$hexdata = pack('H*',$strMessage);
$nLength = strlen($hexdata);
$crc = 0xFFFF;
$pos = 0;
while($nLength > 0)
{
$crc = ($crc >> 8) ^ $CRC16_Table[($crc ^ ord($hexdata[$pos])) & 0xFF];
$nLength--;
$pos++;
}
return ~$crc;
}
Where $strMessage contains packed values, but it does not give the correct result.
Any help will be highly appreciated.

This seems to work, tested with several values against this website for CRC-16-CCITT
Note that it uses PHP strings as direct byte buffers, because it's PHP's closest equivalent to byte[]
<?php
class CRC16 {
private static $CRC16_Table = array
( 0x0000, 0x2110, 0x4220, 0x6330, 0x8440, 0xa550, 0xc660, 0xe770,
0x0881, 0x2991, 0x4aa1, 0x6bb1, 0x8cc1, 0xadd1, 0xcee1, 0xeff1,
0x3112, 0x1002, 0x7332, 0x5222, 0xb552, 0x9442, 0xf772, 0xd662,
0x3993, 0x1883, 0x7bb3, 0x5aa3, 0xbdd3, 0x9cc3, 0xfff3, 0xdee3,
0x6224, 0x4334, 0x2004, 0x0114, 0xe664, 0xc774, 0xa444, 0x8554,
0x6aa5, 0x4bb5, 0x2885, 0x0995, 0xeee5, 0xcff5, 0xacc5, 0x8dd5,
0x5336, 0x7226, 0x1116, 0x3006, 0xd776, 0xf666, 0x9556, 0xb446,
0x5bb7, 0x7aa7, 0x1997, 0x3887, 0xdff7, 0xfee7, 0x9dd7, 0xbcc7,
0xc448, 0xe558, 0x8668, 0xa778, 0x4008, 0x6118, 0x0228, 0x2338,
0xccc9, 0xedd9, 0x8ee9, 0xaff9, 0x4889, 0x6999, 0x0aa9, 0x2bb9,
0xf55a, 0xd44a, 0xb77a, 0x966a, 0x711a, 0x500a, 0x333a, 0x122a,
0xfddb, 0xdccb, 0xbffb, 0x9eeb, 0x799b, 0x588b, 0x3bbb, 0x1aab,
0xa66c, 0x877c, 0xe44c, 0xc55c, 0x222c, 0x033c, 0x600c, 0x411c,
0xaeed, 0x8ffd, 0xeccd, 0xcddd, 0x2aad, 0x0bbd, 0x688d, 0x499d,
0x977e, 0xb66e, 0xd55e, 0xf44e, 0x133e, 0x322e, 0x511e, 0x700e,
0x9fff, 0xbeef, 0xdddf, 0xfccf, 0x1bbf, 0x3aaf, 0x599f, 0x788f,
0x8891, 0xa981, 0xcab1, 0xeba1, 0x0cd1, 0x2dc1, 0x4ef1, 0x6fe1,
0x8010, 0xa100, 0xc230, 0xe320, 0x0450, 0x2540, 0x4670, 0x6760,
0xb983, 0x9893, 0xfba3, 0xdab3, 0x3dc3, 0x1cd3, 0x7fe3, 0x5ef3,
0xb102, 0x9012, 0xf322, 0xd232, 0x3542, 0x1452, 0x7762, 0x5672,
0xeab5, 0xcba5, 0xa895, 0x8985, 0x6ef5, 0x4fe5, 0x2cd5, 0x0dc5,
0xe234, 0xc324, 0xa014, 0x8104, 0x6674, 0x4764, 0x2454, 0x0544,
0xdba7, 0xfab7, 0x9987, 0xb897, 0x5fe7, 0x7ef7, 0x1dc7, 0x3cd7,
0xd326, 0xf236, 0x9106, 0xb016, 0x5766, 0x7676, 0x1546, 0x3456,
0x4cd9, 0x6dc9, 0x0ef9, 0x2fe9, 0xc899, 0xe989, 0x8ab9, 0xaba9,
0x4458, 0x6548, 0x0678, 0x2768, 0xc018, 0xe108, 0x8238, 0xa328,
0x7dcb, 0x5cdb, 0x3feb, 0x1efb, 0xf98b, 0xd89b, 0xbbab, 0x9abb,
0x754a, 0x545a, 0x376a, 0x167a, 0xf10a, 0xd01a, 0xb32a, 0x923a,
0x2efd, 0x0fed, 0x6cdd, 0x4dcd, 0xaabd, 0x8bad, 0xe89d, 0xc98d,
0x267c, 0x076c, 0x645c, 0x454c, 0xa23c, 0x832c, 0xe01c, 0xc10c,
0x1fef, 0x3eff, 0x5dcf, 0x7cdf, 0x9baf, 0xbabf, 0xd98f, 0xf89f,
0x176e, 0x367e, 0x554e, 0x745e, 0x932e, 0xb23e, 0xd10e, 0xf01e
);
public static function calculate( $buffer ) {
$length = strlen($buffer);
$crc = 0;
$i = 0;
while( $length-- ) {
$crc = (( $crc >> 8) & 0xff) ^ (self::$CRC16_Table[(ord($buffer[$i++]) ^ $crc) & 0xFF]);
}
return (($crc & 0xFFFF) ^ 0x8000) - 0x8000;
}
}
echo CRC16::calculate( "\x74\x65\x73\x74" );

It is CRC-16 CCITT, may be it'll help you
<?php
function crc16($data)
{
$crc = 0xFFFF;
for ($i = 0; $i < strlen($data); $i++)
{
$x = (($crc >> 8) ^ ord($data[$i])) & 0xFF;
$x ^= $x >> 4;
$crc = (($crc << 8) ^ ($x << 12) ^ ($x << 5) ^ $x) & 0xFFFF;
}
return $crc;
}
?>

Categories