PHP convert a Byte Array to a Float value

user_19922817 0
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I am reading values over a (modbusTCP) connection. I get back an array with the following data:

print_r($recData) ;
Output: Array ( [0] => 67 [1] => 100 [2] => 33 [3] => 72 )

how do I get the values back as float? as result I should get the following: 229.718

my code dosent work... the data in $recData shout be a Float Big Endian Value

$i = ($recData[0]<<24) + ($recData[1]<<16) + ($recData[2]<<8) + ($recData[3]);
php
1 Answers

You may convert it inside PHP like that.

$number = [67, 100, 33, 72];
$strHex = implode('', array_map('dechex', $number));

$v = hexdec($strHex);
$x = ($v & ((1 << 23) - 1)) + (1 << 23) * ($v >> 31 | 1);
$exp = ($v >> 23 & 0xFF) - 127;
$float = $x * pow(2, $exp - 23);

echo round($float, 3);

gives

228.13
user_26457130
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