Rust - Joystick Bricklet 2.0

This is the description of the Rust API bindings for the Joystick Bricklet 2.0. General information and technical specifications for the Joystick Bricklet 2.0 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).

Simple

Download (example_simple.rs)

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

use tinkerforge::{ip_connection::IpConnection, joystick_v2_bricklet::*};

const HOST: &str = "localhost";
const PORT: u16 = 4223;
const UID: &str = "XYZ"; // Change XYZ to the UID of your Joystick Bricklet 2.0.

fn main() -> Result<(), Box<dyn Error>> {
    let ipcon = IpConnection::new(); // Create IP connection.
    let j = JoystickV2Bricklet::new(UID, &ipcon); // Create device object.

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

    // Get current position.
    let position = j.get_position().recv()?;

    println!("Position [X]: {}", position.x);
    println!("Position [Y]: {}", position.y);

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

Callback

Download (example_callback.rs)

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use std::{error::Error, io, thread};
use tinkerforge::{ip_connection::IpConnection, joystick_v2_bricklet::*};

const HOST: &str = "localhost";
const PORT: u16 = 4223;
const UID: &str = "XYZ"; // Change XYZ to the UID of your Joystick Bricklet 2.0.

fn main() -> Result<(), Box<dyn Error>> {
    let ipcon = IpConnection::new(); // Create IP connection.
    let j = JoystickV2Bricklet::new(UID, &ipcon); // Create device object.

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

    let pressed_receiver = j.get_pressed_callback_receiver();

    // Spawn thread to handle received callback messages.
    // This thread ends when the `j` object
    // is dropped, so there is no need for manual cleanup.
    thread::spawn(move || {
        for pressed in pressed_receiver {
            println!("Pressed: {}", pressed);
        }
    });

    // Set period for pressed callback to 0.01s (10ms).
    j.set_pressed_callback_configuration(10, true);

    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 JoystickV2Bricklet::new(uid: &str, ip_connection: &IpConnection) → JoystickV2Bricklet

Creates a new JoystickV2Bricklet 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 JoystickV2Bricklet::get_position(&self) → ConvertingReceiver<Position>

Returns the position of the joystick. The value ranges between -100 and 100 for both axis. The middle position of the joystick is x=0, y=0. The returned values are averaged and calibrated (see JoystickV2Bricklet::calibrate).

If you want to get the position periodically, it is recommended to use the JoystickV2Bricklet::get_position_callback_receiver callback and set the period with JoystickV2Bricklet::set_position_callback_configuration.

pub fn JoystickV2Bricklet::is_pressed(&self) → ConvertingReceiver<bool>

Returns true if the button is pressed and false otherwise.

If you want to get the press-state periodically, it is recommended to use the JoystickV2Bricklet::get_pressed_callback_receiver callback and set the period with JoystickV2Bricklet::set_pressed_callback_configuration.

Advanced Functions

pub fn JoystickV2Bricklet::calibrate(&self) → ConvertingReceiver<()>

Calibrates the middle position of the joystick. If your Joystick Bricklet 2.0 does not return x=0 and y=0 in the middle position, call this function while the joystick is standing still in the middle position.

The resulting calibration will be saved in non-volatile memory, thus you only have to calibrate it once.

pub fn JoystickV2Bricklet::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 JoystickV2Bricklet::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 JoystickV2Bricklet::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.

See JoystickV2Bricklet::set_response_expected for the list of function ID constants available for this function.

pub fn JoystickV2Bricklet::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 function ID constants are available for this function:

  • JOYSTICK_V2_BRICKLET_FUNCTION_CALIBRATE = 3
  • JOYSTICK_V2_BRICKLET_FUNCTION_SET_POSITION_CALLBACK_CONFIGURATION = 4
  • JOYSTICK_V2_BRICKLET_FUNCTION_SET_PRESSED_CALLBACK_CONFIGURATION = 7
  • JOYSTICK_V2_BRICKLET_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • JOYSTICK_V2_BRICKLET_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • JOYSTICK_V2_BRICKLET_FUNCTION_RESET = 243
  • JOYSTICK_V2_BRICKLET_FUNCTION_WRITE_UID = 248
pub fn JoystickV2Bricklet::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 JoystickV2Bricklet::get_spitfp_error_count(&self) → ConvertingReceiver<SpitfpErrorCount>

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.

pub fn JoystickV2Bricklet::set_bootloader_mode(&self, mode: u8) → ConvertingReceiver<u8>

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.

The following constants are available for this function:

  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_BOOTLOADER = 0
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE = 1
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_STATUS_OK = 0
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_STATUS_INVALID_MODE = 1
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_STATUS_NO_CHANGE = 2
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_STATUS_CRC_MISMATCH = 5
pub fn JoystickV2Bricklet::get_bootloader_mode(&self) → ConvertingReceiver<u8>

Returns the current bootloader mode, see JoystickV2Bricklet::set_bootloader_mode.

The following constants are available for this function:

  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_BOOTLOADER = 0
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE = 1
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • JOYSTICK_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
pub fn JoystickV2Bricklet::set_write_firmware_pointer(&self, pointer: u32) → ConvertingReceiver<()>

Sets the firmware pointer for JoystickV2Bricklet::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).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

pub fn JoystickV2Bricklet::write_firmware(&self, data: [u8; 64]) → ConvertingReceiver<u8>

Writes 64 Bytes of firmware at the position as written by JoystickV2Bricklet::set_write_firmware_pointer before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

pub fn JoystickV2Bricklet::set_status_led_config(&self, config: u8) → ConvertingReceiver<()>

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.

The following constants are available for this function:

  • JOYSTICK_V2_BRICKLET_STATUS_LED_CONFIG_OFF = 0
  • JOYSTICK_V2_BRICKLET_STATUS_LED_CONFIG_ON = 1
  • JOYSTICK_V2_BRICKLET_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • JOYSTICK_V2_BRICKLET_STATUS_LED_CONFIG_SHOW_STATUS = 3
pub fn JoystickV2Bricklet::get_status_led_config(&self) → ConvertingReceiver<u8>

Returns the configuration as set by JoystickV2Bricklet::set_status_led_config

The following constants are available for this function:

  • JOYSTICK_V2_BRICKLET_STATUS_LED_CONFIG_OFF = 0
  • JOYSTICK_V2_BRICKLET_STATUS_LED_CONFIG_ON = 1
  • JOYSTICK_V2_BRICKLET_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • JOYSTICK_V2_BRICKLET_STATUS_LED_CONFIG_SHOW_STATUS = 3
pub fn JoystickV2Bricklet::get_chip_temperature(&self) → ConvertingReceiver<i16>

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.

pub fn JoystickV2Bricklet::reset(&self) → ConvertingReceiver<()>

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!

pub fn JoystickV2Bricklet::write_uid(&self, uid: u32) → ConvertingReceiver<()>

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.

pub fn JoystickV2Bricklet::read_uid(&self) → ConvertingReceiver<u32>

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

pub fn JoystickV2Bricklet::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.

Callback Configuration Functions

pub fn JoystickV2Bricklet::set_position_callback_configuration(&self, period: u32, value_has_to_change: bool) → ConvertingReceiver<()>

The period in ms is the period with which the JoystickV2Bricklet::get_position_callback_receiver 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 at least one of the values has changed. If the values 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.

The default value is (0, false).

pub fn JoystickV2Bricklet::get_position_callback_configuration(&self) → ConvertingReceiver<PositionCallbackConfiguration>

Returns the callback configuration as set by JoystickV2Bricklet::set_position_callback_configuration.

pub fn JoystickV2Bricklet::set_pressed_callback_configuration(&self, period: u32, value_has_to_change: bool) → ConvertingReceiver<()>

The period in ms is the period with which the JoystickV2Bricklet::get_pressed_callback_receiver 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 at least one of the values has changed. If the values 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.

The default value is (0, false).

pub fn JoystickV2Bricklet::get_pressed_callback_configuration(&self) → ConvertingReceiver<PressedCallbackConfiguration>

Returns the callback configuration as set by JoystickV2Bricklet::set_pressed_callback_configuration.

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 JoystickV2Bricklet::get_position_callback_receiver(&self) → ConvertingCallbackReceiver<PositionEvent>

Receivers created with this function receive Position events.

This callback is triggered periodically according to the configuration set by JoystickV2Bricklet::set_position_callback_configuration.

The members of the received struct are the same as with JoystickV2Bricklet::get_position.

pub fn JoystickV2Bricklet::get_pressed_callback_receiver(&self) → ConvertingCallbackReceiver<bool>

Receivers created with this function receive Pressed events.

This callback is triggered periodically according to the configuration set by JoystickV2Bricklet::set_pressed_callback_configuration.

The members of the received struct are the same as with JoystickV2Bricklet::is_pressed.

Constants

JoystickV2Bricklet::DEVICE_IDENTIFIER

This constant is used to identify a Joystick Bricklet 2.0.

The JoystickV2Bricklet::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.

JoystickV2Bricklet::DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Joystick Bricklet 2.0.