Rust - Piezo Speaker Bricklet

This is the description of the Rust API bindings for the Piezo Speaker Bricklet. General information and technical specifications for the Piezo Speaker Bricklet are summarized in its hardware description.

An installation guide for the Rust API bindings is part of their general description. Additional documentation can be found on docs.rs.

Examples

The example code below is Public Domain (CC0 1.0).

Beep

Download (example_beep.rs)

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use std::{error::Error, io};

use tinkerforge::{ip_connection::IpConnection, piezo_speaker_bricklet::*};

const HOST: &str = "localhost";
const PORT: u16 = 4223;
const UID: &str = "XYZ"; // Change XYZ to the UID of your Piezo Speaker Bricklet.

fn main() -> Result<(), Box<dyn Error>> {
    let ipcon = IpConnection::new(); // Create IP connection.
    let ps = PiezoSpeakerBricklet::new(UID, &ipcon); // Create device object.

    ipcon.connect((HOST, PORT)).recv()??; // Connect to brickd.
                                          // Don't use device before ipcon is connected.

    // Make 2 second beep with a frequency of 1kHz
    ps.beep(2000, 1000);

    println!("Press enter to exit.");
    let mut _input = String::new();
    io::stdin().read_line(&mut _input)?;
    ipcon.disconnect();
    Ok(())
}

Morse Code

Download (example_morse_code.rs)

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use std::{error::Error, io};

use tinkerforge::{ip_connection::IpConnection, piezo_speaker_bricklet::*};

const HOST: &str = "localhost";
const PORT: u16 = 4223;
const UID: &str = "XYZ"; // Change XYZ to the UID of your Piezo Speaker Bricklet.

fn main() -> Result<(), Box<dyn Error>> {
    let ipcon = IpConnection::new(); // Create IP connection.
    let ps = PiezoSpeakerBricklet::new(UID, &ipcon); // Create device object.

    ipcon.connect((HOST, PORT)).recv()??; // Connect to brickd.
                                          // Don't use device before ipcon is connected.

    // Morse SOS with a frequency of 2kHz
    ps.morse_code("... --- ...".to_string(), 2000);

    println!("Press enter to exit.");
    let mut _input = String::new();
    io::stdin().read_line(&mut _input)?;
    ipcon.disconnect();
    Ok(())
}

API

To allow non-blocking usage, nearly every function of the Rust bindings returns a wrapper around a mpsc::Receiver. To block until the function has finished and get your result, call one of the receiver's recv variants. Those return either the result sent by the device, or any error occured.

Functions returning a result directly will block until the device has finished processing the request.

All functions listed below are thread-safe, those which return a receiver are lock-free.

Basic Functions

pub fn PiezoSpeakerBricklet::new(uid: &str, ip_connection: &IpConnection) → PiezoSpeakerBricklet

Creates a new PiezoSpeakerBricklet object with the unique device ID uid and adds it to the IPConnection ipcon:

This device object can be used after the IP connection has been connected (see examples above).

pub fn PiezoSpeakerBricklet::beep(&self, duration: u32, frequency: u16) → ConvertingReceiver<()>

Beeps with the given frequency for the duration in ms. For example: If you set a duration of 1000, with a frequency value of 2000 the piezo buzzer will beep for one second with a frequency of approximately 2 kHz.

Changed in version 2.0.2 (Plugin): A duration of 0 stops the current beep if any, the frequency parameter is ignored. A duration of 4294967295 results in an infinite beep.

The frequency parameter can be set between 585 and 7100.

The Piezo Speaker Bricklet can only approximate the frequency, it will play the best possible match by applying the calibration (see PiezoSpeakerBricklet::calibrate).

The following constants are available for this function:

  • PIEZO_SPEAKER_BRICKLET_BEEP_DURATION_OFF = 0
  • PIEZO_SPEAKER_BRICKLET_BEEP_DURATION_INFINITE = 4294967295
pub fn PiezoSpeakerBricklet::morse_code(&self, morse: String, frequency: u16) → ConvertingReceiver<()>

Sets morse code that will be played by the piezo buzzer. The morse code is given as a string consisting of "." (dot), "-" (minus) and " " (space) for dits, dahs and pauses. Every other character is ignored. The second parameter is the frequency (see PiezoSpeakerBricklet::beep).

For example: If you set the string "...---...", the piezo buzzer will beep nine times with the durations "short short short long long long short short short".

The maximum string size is 60.

Advanced Functions

pub fn PiezoSpeakerBricklet::calibrate(&self) → ConvertingReceiver<bool>

The Piezo Speaker Bricklet can play 512 different tones. This function plays each tone and measures the exact frequency back. The result is a mapping between setting value and frequency. This mapping is stored in the EEPROM and loaded on startup.

The Bricklet should come calibrated, you only need to call this function (once) every time you reflash the Bricklet plugin.

Returns true after the calibration finishes.

pub fn PiezoSpeakerBricklet::get_api_version(&self) → [u8; 3]

Returns the version of the API definition (major, minor, revision) implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

pub fn PiezoSpeakerBricklet::get_response_expected(&mut self, function_id: u8) → bool

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by PiezoSpeakerBricklet::set_response_expected. For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

  • PIEZO_SPEAKER_BRICKLET_FUNCTION_BEEP = 1
  • PIEZO_SPEAKER_BRICKLET_FUNCTION_MORSE_CODE = 2
pub fn PiezoSpeakerBricklet::set_response_expected(&mut self, function_id: u8, response_expected: bool) → ()

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

  • PIEZO_SPEAKER_BRICKLET_FUNCTION_BEEP = 1
  • PIEZO_SPEAKER_BRICKLET_FUNCTION_MORSE_CODE = 2
pub fn PiezoSpeakerBricklet::set_response_expected_all(&mut self, response_expected: bool) → ()

Changes the response expected flag for all setter and callback configuration functions of this device at once.

pub fn PiezoSpeakerBricklet::get_identity(&self) → ConvertingReceiver<Identity>

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 here. There is also a constant for the device identifier of this Bricklet.

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the corresponding get_*_callback_receiver function, which returns a receiver for callback events.

Note

Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

pub fn PiezoSpeakerBricklet::get_beep_finished_callback_receiver(&self) → ConvertingCallbackReceiver<()>

Receivers created with this function receive Beep Finished events.

This callback is triggered if a beep set by PiezoSpeakerBricklet::beep is finished
pub fn PiezoSpeakerBricklet::get_morse_code_finished_callback_receiver(&self) → ConvertingCallbackReceiver<()>

Receivers created with this function receive Morse Code Finished events.

This callback is triggered if the playback of the morse code set by PiezoSpeakerBricklet::morse_code is finished.

Constants

PiezoSpeakerBricklet::DEVICE_IDENTIFIER

This constant is used to identify a Piezo Speaker Bricklet.

The PiezoSpeakerBricklet::get_identity function and the IpConnection::get_enumerate_callback_receiver callback of the IP Connection have a device_identifier parameter to specify the Brick's or Bricklet's type.

PiezoSpeakerBricklet::DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Piezo Speaker Bricklet.