NAME

Device::Chip::BME280 - chip driver for BME280

SYNOPSIS

   use Device::Chip::BME280;
   use Future::AsyncAwait;

   my $chip = Device::Chip::BME280->new;
   await $chip->mount( Device::Chip::Adapter::...->new );

   await $chip->change_config(
      OSRS_H => 4,
      OSRS_P => 4,
      OSRS_T => 4,
      MODE   => "NORMAL",
   );

   my ( $pressure, $temperature, $humidity ) = await $chip->read_sensor;

   printf "Temperature=%.2fC  ", $temperature;
   printf "Pressure=%dPa  ", $pressure;
   printf "Humidity=%.2f%%\n", $humidity;

DESCRIPTION

This Device::Chip subclass provides specific communication to a Bosch BME280 attached to a computer via an I²C adapter.

The reader is presumed to be familiar with the general operation of this chip; the documentation here will not attempt to explain or define chip-specific concepts or features, only the use of this module to access them.

METHODS

The following methods documented in an await expression return Future instances.

read_id

   $id = await $chip->read_id

Returns the chip ID.

read_config

   $config = await $chip->read_config

Returns a HASH reference containing the chip config, using fields named from the data sheet.

   FILTER   => OFF | 2 | 4 | 8 | 16
   MODE     => SLEEP | FORCED | NORMAL
   OSRS_H   => SKIP | 1 | 2 | 4 | 8 | 16
   OSRS_P   => SKIP | 1 | 2 | 4 | 8 | 16
   OSRS_T   => SKIP | 1 | 2 | 4 | 8 | 16
   SPI3W_EN => 0 | 1
   T_SB     => 0.5 | 10 | 20 | 62.5 | 125 | 250 | 500 | 1000

change_config

   await $chip->change_config( %changes )

Writes updates to the configuration registers.

Note that these two methods use a cache of configuration bytes to make subsequent modifications more efficient.

read_status

   $status = await $chip->read_status;

read_raw

   ( $adc_P, $adc_T, $adc_H ) = await $chip->read_raw

Returns three integers containing the raw ADC reading values from the sensor.

This method is mostly for testing or internal purposes only. For converted sensor readings in real-world units you want to use "read_sensor".

read_sensor

   ( $pressure, $temperature, $humidity ) = await $chip->read_sensor

Returns the sensor readings appropriately converted into units of Pascals for pressure, degrees Celcius for temperature, and percentage relative for humidity.

AUTHOR

Paul Evans <leonerd@leonerd.org.uk>

cpanm Device::Chip::BME280

perl -MCPAN -e shell
install Device::Chip::BME280