Tinkerforge::BrickletSoundPressureLevel - Measures Sound Pressure Level in dB(A/B/C/D/Z)
This constant is used to identify a Sound Pressure Level Bricklet.
The get_identity() subroutine and the CALLBACK_ENUMERATE callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.
This constant represents the display name of a Sound Pressure Level Bricklet.
This constant is used with the register_callback() subroutine to specify the CALLBACK_DECIBEL callback.
This constant is used with the register_callback() subroutine to specify the CALLBACK_SPECTRUM_LOW_LEVEL callback.
This constant is used with the register_callback() subroutine to specify the CALLBACK_SPECTRUM callback.
This constant is used with the get_response_expected(), set_response_expected() and set_response_expected_all() subroutines.
Creates an object with the unique device ID *uid* and adds it to the IP Connection *ipcon*.
Returns the measured sound pressure in decibels. The values are given in dB/10 (tenths dB).
The Bricklet supports the weighting standards dB(A), dB(B), dB(C), dB(D), dB(Z) and ITU-R 468. You can configure the weighting with :func:`Set Configuration`.
By default dB(A) will be used.
If you want to get the value periodically, it is recommended to use the :cb:`Decibel` callback. You can set the callback configuration with :func:`Set Decibel Callback Configuration`.
The period in ms is the period with which the :cb:`Decibel` callback is triggered periodically. A value of 0 turns the callback off.
If the `value has to change`-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
It is furthermore possible to constrain the callback with thresholds.
The `option`-parameter together with min/max sets a threshold for the :cb:`Decibel` callback.
The following options are possible:
.. csv-table:: :header: "Option", "Description" :widths: 10, 100
"'x'", "Threshold is turned off" "'o'", "Threshold is triggered when the value is *outside* the min and max values" "'i'", "Threshold is triggered when the value is *inside* or equal to the min and max values" "'<'", "Threshold is triggered when the value is smaller than the min value (max is ignored)" "'>'", "Threshold is triggered when the value is greater than the min value (max is ignored)"
If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.
The default value is (0, false, 'x', 0, 0).
Returns the callback configuration as set by :func:`Set Decibel Callback Configuration`.
Returns the frequency spectrum. The length of the spectrum is between 512 (FFT size 1024) and 64 (FFT size 128). See :func:`Set Configuration`.
Each array element is one bin of the FFT. The first bin is always the DC offset and the other bins have a size between 40Hz (FFT size 1024) and 320Hz (FFT size 128).
In sum the frequency of the spectrum always has a range from 0 to 20480Hz (the FFT is applied to samples with a frequency of 40960Hz).
The returned data is already equalized, which means that the microphone frequency response is compensated and the weighting function is applied (see :func:`Set Configuration` for the available weighting standards). Use dB(Z) if you need the unaltered spectrum.
The values are not in dB form yet. If you want a proper dB scale of the spectrum you have to apply the formula f(x) = 20*log10(max(1, x/sqrt(2))) on each value.
The period in ms is the period with which the :cb:`Spectrum` callback is triggered periodically. A value of 0 turns the callback off.
Every new measured spectrum will be send at most once. Set the period to 1 to make sure that you get every spectrum.
The default value is 0.
Returns the callback configuration as set by :func:`Get Spectrum Callback Configuration`.
Sets the Sound Pressure Level Bricklet configuration.
With different FFT sizes the Bricklet has a different amount of samples per second and the size of the FFT bins changes. The higher the FFT size the more precise is the result of the dB(X) calculation.
Available FFT sizes are:
* 1024: 512 bins, 10 samples per second, each bin has size 40Hz * 512: 256 bins, 20 samples per second, each bin has size 80Hz * 256: 128 bins, 40 samples per second, each bin has size 160Hz * 128: 64 bins, 80 samples per second, each bin has size 320Hz
The Bricklet supports different weighting functions. You can choose between dB(A), dB(B), dB(C), dB(D), dB(Z) and ITU-R 468.
dB(A/B/C/D) are the standard dB weighting curves. dB(A) is often used to measure volumes at concerts etc. dB(Z) has a flat response, no weighting is applied. ITU-R 468 is an ITU weighting standard mostly used in the UK and Europe.
The defaults are FFT size 1024 and weighting standard dB(A).
Returns the configuration as set by :func:`Set Configuration`.
Returns the error count for the communication between Brick and Bricklet.
The errors are divided into
* ACK checksum errors, * message checksum errors, * framing errors and * overflow errors.
The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.
Sets the bootloader mode and returns the status after the requested mode change was instigated.
You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
Returns the current bootloader mode, see :func:`Set Bootloader Mode`.
Sets the firmware pointer for :func:`Write Firmware`. The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).
Writes 64 Bytes of firmware at the position as written by :func:`Set Write Firmware Pointer` before. The firmware is written to flash every 4 chunks.
You can only write firmware in bootloader mode.
Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.
You can also turn the LED permanently on/off or show a heartbeat.
If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.
Returns the configuration as set by :func:`Set Status LED Config`
Returns the temperature in °C as measured inside the microcontroller. The value returned is not the ambient temperature!
The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.
Calling this function will reset the Bricklet. All configurations will be lost.
After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!
Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.
We recommend that you use Brick Viewer to change the UID.
Returns the current UID as an integer. Encode as Base58 to get the usual string version.
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c' or 'd'.
The device identifier numbers can be found :ref:`here <device_identifier>`. |device_identifier_constant|
To install Tinkerforge, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Tinkerforge
CPAN shell
perl -MCPAN -e shell install Tinkerforge
For more information on module installation, please visit the detailed CPAN module installation guide.