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uphp:functions:ow_first

ow_first

WMPRO >= 1.0 WMMEGA FW >= 2.0

Initiate a OneWire bus scan and return the address of the first device found

Description

mixed ow_first ( )

This function starts a new OneWire bus scan and provides the address of the first device found. Currently only DS18B20 temperature sensors are detectable.

Parameters

None

Return Values

An array of 8 elements containing the unique OneWire address. Returns int 0 if no devices were detected.

Example

<?
  $arr=ow_first();
  if ($arr) {
    $devname=sprintf("%02X%02X%02X%02X%02X%02X%02X%02X",$arr[0],$arr[1],$arr[2],$arr[3],$arr[4],$arr[5],$arr[6],$arr[7]);
    print("Detected the first OneWire device ".$devname);
  } else {
    print("No devices detected.");
  }
?>

See Also

ow_next() - Return the address of the next OneWire device found (after an ow_first)

ow_read() - Read a byte from the OneWire bus

ow_read_temp() - Read a temperature from a device on the OneWire bus

ow_reset() - Reset the OneWire bus

ow_write() - Write a byte to the OneWire bus

sprintf() - Return a formatted string

uphp/functions/ow_first.txt · Last modified: 2021/09/13 05:57 (external edit)