Software / API Bindings / Rust / API Reference and Examples / Bricklets / RS232 Bricklet

Rust - RS232 Bricklet¶

This is the description of the Rust API bindings for the RS232 Bricklet. General information and technical specifications for the RS232 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).

Loopback¶

Download (example_loopback.rs)

use std::{error::Error, io, thread};
use tinkerforge::{ip_connection::IpConnection, rs232_bricklet::*};

// For this example connect the RX1 and TX pin to receive the send message

const HOST: &str = "localhost";
const PORT: u16 = 4223;
const UID: &str = "XYZ"; // Change XYZ to the UID of your RS232 Bricklet.

fn main() -> Result<(), Box<dyn Error>> {
    let ipcon = IpConnection::new(); // Create IP connection.
    let rs232 = Rs232Bricklet::new(UID, &ipcon); // Create device object.

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

    let read_receiver = rs232.get_read_callback_receiver();

    // Spawn thread to handle received callback messages.
    // This thread ends when the `rs232` object
    // is dropped, so there is no need for manual cleanup.
    thread::spawn(move || {
        for read in read_receiver {
            let message: String = read.message.iter().collect();
            println!("Message (Length: {}) {}", read.length, message);
        }
    });

    // Enable read callback
    rs232.enable_read_callback();

    let mut chars = ['\0'; 60];
    let test_chars = ['t', 'e', 's', 't'];
    chars[0..4].copy_from_slice(&test_chars);

    // Write "test" string
    rs232.write(chars, 4);

    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 occurred.

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 Rs232Bricklet::new(uid: &str, ip_connection: &IpConnection) → Rs232Bricklet¶

Parameters:	uid – Type: &str ip_connection – Type: &IPConnection
Returns:	rs232 – Type: Rs232Bricklet

Creates a new Rs232Bricklet object with the unique device ID uid and adds it to the IPConnection ip_connection:

let rs232 = Rs232Bricklet::new("YOUR_DEVICE_UID", &ip_connection);

This device object can be used after the IP connection has been connected.

pub fn Rs232Bricklet::write(&self, message: [char; 60], length: u8) → ConvertingReceiver<u8>¶

Parameters:	message – Type: [char; 60] length – Type: u8, Range: [0 to 60]
Returns:	written – Type: u8, Range: [0 to 60]

Writes a string of up to 60 characters to the RS232 interface. The string can be binary data, ASCII or similar is not necessary.

The length of the string has to be given as an additional parameter.

The return value is the number of bytes that could be written.

See Rs232Bricklet::set_configuration for configuration possibilities regarding baudrate, parity and so on.

pub fn Rs232Bricklet::read(&self) → ConvertingReceiver<Read>¶

Return Object:	message – Type: [char; 60] length – Type: u8, Range: [0 to 60]

Returns the currently buffered message. The maximum length of message is 60. If the returned length is 0, no new data was available.

Instead of polling with this function, you can also use callbacks. See Rs232Bricklet::enable_read_callback and Rs232Bricklet::get_read_callback_receiver callback.

pub fn Rs232Bricklet::set_configuration(&self, baudrate: u8, parity: u8, stopbits: u8, wordlength: u8, hardware_flowcontrol: u8, software_flowcontrol: u8) → ConvertingReceiver<()>¶

Parameters:	baudrate – Type: u8, Range: See constants, Default: 11 parity – Type: u8, Range: See constants, Default: 0 stopbits – Type: u8, Range: See constants, Default: 1 wordlength – Type: u8, Range: See constants, Default: 8 hardware_flowcontrol – Type: u8, Range: See constants, Default: 0 software_flowcontrol – Type: u8, Range: See constants, Default: 0

Sets the configuration for the RS232 communication.

Hard-/Software flow control can either be on or off but not both simultaneously on.

The following constants are available for this function:

For baudrate:

RS232_BRICKLET_BAUDRATE_300 = 0
RS232_BRICKLET_BAUDRATE_600 = 1
RS232_BRICKLET_BAUDRATE_1200 = 2
RS232_BRICKLET_BAUDRATE_2400 = 3
RS232_BRICKLET_BAUDRATE_4800 = 4
RS232_BRICKLET_BAUDRATE_9600 = 5
RS232_BRICKLET_BAUDRATE_14400 = 6
RS232_BRICKLET_BAUDRATE_19200 = 7
RS232_BRICKLET_BAUDRATE_28800 = 8
RS232_BRICKLET_BAUDRATE_38400 = 9
RS232_BRICKLET_BAUDRATE_57600 = 10
RS232_BRICKLET_BAUDRATE_115200 = 11
RS232_BRICKLET_BAUDRATE_230400 = 12

For parity:

RS232_BRICKLET_PARITY_NONE = 0
RS232_BRICKLET_PARITY_ODD = 1
RS232_BRICKLET_PARITY_EVEN = 2
RS232_BRICKLET_PARITY_FORCED_PARITY_1 = 3
RS232_BRICKLET_PARITY_FORCED_PARITY_0 = 4

For stopbits:

RS232_BRICKLET_STOPBITS_1 = 1
RS232_BRICKLET_STOPBITS_2 = 2

For wordlength:

RS232_BRICKLET_WORDLENGTH_5 = 5
RS232_BRICKLET_WORDLENGTH_6 = 6
RS232_BRICKLET_WORDLENGTH_7 = 7
RS232_BRICKLET_WORDLENGTH_8 = 8

For hardware_flowcontrol:

RS232_BRICKLET_HARDWARE_FLOWCONTROL_OFF = 0
RS232_BRICKLET_HARDWARE_FLOWCONTROL_ON = 1

For software_flowcontrol:

RS232_BRICKLET_SOFTWARE_FLOWCONTROL_OFF = 0
RS232_BRICKLET_SOFTWARE_FLOWCONTROL_ON = 1

pub fn Rs232Bricklet::get_configuration(&self) → ConvertingReceiver<Configuration>¶

Return Object:	baudrate – Type: u8, Range: See constants, Default: 11 parity – Type: u8, Range: See constants, Default: 0 stopbits – Type: u8, Range: See constants, Default: 1 wordlength – Type: u8, Range: See constants, Default: 8 hardware_flowcontrol – Type: u8, Range: See constants, Default: 0 software_flowcontrol – Type: u8, Range: See constants, Default: 0

Returns the configuration as set by Rs232Bricklet::set_configuration.

The following constants are available for this function:

For baudrate:

RS232_BRICKLET_BAUDRATE_300 = 0
RS232_BRICKLET_BAUDRATE_600 = 1
RS232_BRICKLET_BAUDRATE_1200 = 2
RS232_BRICKLET_BAUDRATE_2400 = 3
RS232_BRICKLET_BAUDRATE_4800 = 4
RS232_BRICKLET_BAUDRATE_9600 = 5
RS232_BRICKLET_BAUDRATE_14400 = 6
RS232_BRICKLET_BAUDRATE_19200 = 7
RS232_BRICKLET_BAUDRATE_28800 = 8
RS232_BRICKLET_BAUDRATE_38400 = 9
RS232_BRICKLET_BAUDRATE_57600 = 10
RS232_BRICKLET_BAUDRATE_115200 = 11
RS232_BRICKLET_BAUDRATE_230400 = 12

For parity:

RS232_BRICKLET_PARITY_NONE = 0
RS232_BRICKLET_PARITY_ODD = 1
RS232_BRICKLET_PARITY_EVEN = 2
RS232_BRICKLET_PARITY_FORCED_PARITY_1 = 3
RS232_BRICKLET_PARITY_FORCED_PARITY_0 = 4

For stopbits:

RS232_BRICKLET_STOPBITS_1 = 1
RS232_BRICKLET_STOPBITS_2 = 2

For wordlength:

RS232_BRICKLET_WORDLENGTH_5 = 5
RS232_BRICKLET_WORDLENGTH_6 = 6
RS232_BRICKLET_WORDLENGTH_7 = 7
RS232_BRICKLET_WORDLENGTH_8 = 8

For hardware_flowcontrol:

RS232_BRICKLET_HARDWARE_FLOWCONTROL_OFF = 0
RS232_BRICKLET_HARDWARE_FLOWCONTROL_ON = 1

For software_flowcontrol:

RS232_BRICKLET_SOFTWARE_FLOWCONTROL_OFF = 0
RS232_BRICKLET_SOFTWARE_FLOWCONTROL_ON = 1

pub fn Rs232Bricklet::set_break_condition(&self, break_time: u16) → ConvertingReceiver<()>¶

Parameters:	break_time – Type: u16, Unit: 1 ms, Range: [0 to 2¹⁶ - 1]

Sets a break condition (the TX output is forced to a logic 0 state). The parameter sets the hold-time of the break condition.

New in version 2.0.2 (Plugin).

pub fn Rs232Bricklet::read_frame(&self) → ConvertingReceiver<ReadFrame>¶

Return Object:	message – Type: [char; 60] length – Type: u8, Range: [0 to 60]

Returns up to one frame of bytes from the read buffer. The frame size is configured with Rs232Bricklet::set_frame_readable_callback_configuration. If the returned length is 0, no new data was available.

New in version 2.0.4 (Plugin).

Advanced Functions¶

pub fn Rs232Bricklet::get_identity(&self) → ConvertingReceiver<Identity>¶

Return Object:

Return Object:	uid – Type: String, Length: up to 8 connected_uid – Type: String, Length: up to 8 position – Type: char, Range: ['a' to 'h', 'z'] hardware_version – Type: [u8; 3] 0: major – Type: u8, Range: [0 to 255] 1: minor – Type: u8, Range: [0 to 255] 2: revision – Type: u8, Range: [0 to 255] firmware_version – Type: [u8; 3] 0: major – Type: u8, Range: [0 to 255] 1: minor – Type: u8, Range: [0 to 255] 2: revision – Type: u8, Range: [0 to 255] device_identifier – Type: u16, Range: [0 to 2¹⁶ - 1]

uid – Type: String, Length: up to 8
connected_uid – Type: String, Length: up to 8
position – Type: char, Range: ['a' to 'h', 'z']
hardware_version – Type: [u8; 3]

0: major – Type: u8, Range: [0 to 255]
1: minor – Type: u8, Range: [0 to 255]
2: revision – Type: u8, Range: [0 to 255]

firmware_version – Type: [u8; 3]

0: major – Type: u8, Range: [0 to 255]
1: minor – Type: u8, Range: [0 to 255]
2: revision – Type: u8, Range: [0 to 255]

device_identifier – Type: u16, Range: [0 to 2¹⁶ - 1]

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', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.

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 Rs232Bricklet::enable_read_callback(&self) → ConvertingReceiver<()>¶

Enables the Rs232Bricklet::get_read_callback_receiver callback. This will disable the Rs232Bricklet::get_frame_readable_callback_receiver callback.

By default the callback is disabled.

pub fn Rs232Bricklet::disable_read_callback(&self) → ConvertingReceiver<()>¶

Disables the Rs232Bricklet::get_read_callback_receiver callback.

By default the callback is disabled.

pub fn Rs232Bricklet::is_read_callback_enabled(&self) → ConvertingReceiver<bool>¶

Returns:	enabled – Type: bool, Default: false

Returns true if the Rs232Bricklet::get_read_callback_receiver callback is enabled, false otherwise.

pub fn Rs232Bricklet::set_frame_readable_callback_configuration(&self, frame_size: u8) → ConvertingReceiver<()>¶

Parameters:	frame_size – Type: u8, Unit: 1 B, Range: [0 to 100], Default: 0

Configures the Rs232Bricklet::get_frame_readable_callback_receiver callback. The frame size is the number of bytes, that have to be readable to trigger the callback. A frame size of 0 disables the callback. A frame size greater than 0 enables the callback and disables the Rs232Bricklet::get_read_callback_receiver callback.

By default the callback is disabled.

New in version 2.0.4 (Plugin).

pub fn Rs232Bricklet::get_frame_readable_callback_configuration(&self) → ConvertingReceiver<u8>¶

Returns:	frame_size – Type: u8, Unit: 1 B, Range: [0 to 100], Default: 0

Returns the callback configuration as set by Rs232Bricklet::set_frame_readable_callback_configuration.

New in version 2.0.4 (Plugin).

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 Rs232Bricklet::get_read_callback_receiver(&self) → ConvertingCallbackReceiver<ReadEvent>¶

Event Object:	message – Type: [char; 60] length – Type: u8, Range: [1 to 60]

Receivers created with this function receive Read events.

This callback is called if new data is available. The message has a maximum size of 60 characters. The actual length of the message is given in addition.

To enable this callback, use Rs232Bricklet::enable_read_callback.

pub fn Rs232Bricklet::get_error_callback_receiver(&self) → ConvertingCallbackReceiver<u8>¶

Event:	error – Type: u8, Range: See constants

Receivers created with this function receive Error events.

This callback is called if an error occurs. Possible errors are overrun, parity or framing error.

The following constants are available for this function:

For error:

RS232_BRICKLET_ERROR_OVERRUN = 1
RS232_BRICKLET_ERROR_PARITY = 2
RS232_BRICKLET_ERROR_FRAMING = 4

New in version 2.0.1 (Plugin).

pub fn Rs232Bricklet::get_frame_readable_callback_receiver(&self) → ConvertingCallbackReceiver<u8>¶

Event:	frame_count – Type: u8, Range: [0 to 255]

Receivers created with this function receive Frame Readable events.

This callback is called if at least one frame of data is readable. The frame size is configured with Rs232Bricklet::set_frame_readable_callback_configuration. The frame count parameter is the number of frames that can be read. This callback is triggered only once until Rs232Bricklet::read or Rs232Bricklet::read_frame is called. This means, that if you have configured a frame size of X bytes, you can read exactly X bytes using the Rs232Bricklet::read_frame function, every time the callback triggers without checking the frame count received variable.

New in version 2.0.4 (Plugin).

Virtual Functions¶

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.

pub fn Rs232Bricklet::get_api_version(&self) → [u8; 3]¶

Return Object:	api_version – Type: [u8; 3] 0: major – Type: u8, Range: [0 to 255] 1: minor – Type: u8, Range: [0 to 255] 2: revision – Type: u8, Range: [0 to 255]

Returns the version of the API definition 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 Rs232Bricklet::get_response_expected(&mut self, function_id: u8) → bool¶

Parameters:	function_id – Type: u8, Range: See constants
Returns:	response_expected – Type: 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 Rs232Bricklet::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 sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For function_id:

RS232_BRICKLET_FUNCTION_ENABLE_READ_CALLBACK = 3
RS232_BRICKLET_FUNCTION_DISABLE_READ_CALLBACK = 4
RS232_BRICKLET_FUNCTION_SET_CONFIGURATION = 6
RS232_BRICKLET_FUNCTION_SET_BREAK_CONDITION = 10
RS232_BRICKLET_FUNCTION_SET_FRAME_READABLE_CALLBACK_CONFIGURATION = 11

pub fn Rs232Bricklet::set_response_expected(&mut self, function_id: u8, response_expected: bool) → ()¶

Parameters:	function_id – Type: u8, Range: See constants response_expected – Type: 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.

The following constants are available for this function:

For function_id:

RS232_BRICKLET_FUNCTION_ENABLE_READ_CALLBACK = 3
RS232_BRICKLET_FUNCTION_DISABLE_READ_CALLBACK = 4
RS232_BRICKLET_FUNCTION_SET_CONFIGURATION = 6
RS232_BRICKLET_FUNCTION_SET_BREAK_CONDITION = 10
RS232_BRICKLET_FUNCTION_SET_FRAME_READABLE_CALLBACK_CONFIGURATION = 11

pub fn Rs232Bricklet::set_response_expected_all(&mut self, response_expected: bool) → ()¶

Parameters:	response_expected – Type: bool

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

Constants¶

pub const Rs232Bricklet::DEVICE_IDENTIFIER¶

This constant is used to identify a RS232 Bricklet.

The Rs232Bricklet::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.

pub const Rs232Bricklet::DEVICE_DISPLAY_NAME¶: This constant represents the human readable name of a RS232 Bricklet.