Rust - RS232 Bricklet 2.0

This is the description of the Rust API bindings for the RS232 Bricklet 2.0. General information and technical specifications for the RS232 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).

Loopback

Download (example_loopback.rs)

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use std::{error::Error, io, thread};
use tinkerforge::{ip_connection::IpConnection, rs232_v2_bricklet::*};

// For this example connect the RX pin to the TX pin on the same Bricklet

const HOST: &str = "127.0.0.1";
const PORT: u16 = 4223;
const UID: &str = "XYZ"; // Change XYZ to the UID of your RS232 Bricklet 2.0

fn main() -> Result<(), Box<dyn Error>> {
    let ipcon = IpConnection::new(); // Create IP connection
    let rs232 = Rs232V2Bricklet::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 events.
    // 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 {
            match read {
                Some((payload, _)) => {
                    let message: String = payload.iter().collect();
                    println!("Message (Length: {}) {}", message.len(), message);
                }
                None => println!("Stream was out of sync."),
            }
        }
    });

    // Enable read callback
    rs232.enable_read_callback();

    // Write "test" string
    rs232.write(&['t', 'e', 's', 't'])?;

    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 Rs232V2Bricklet::new(uid: &str, ip_connection: &IpConnection) → Rs232V2Bricklet

Creates a new Rs232V2Bricklet 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 Rs232V2Bricklet::write(&self, message: char) → Result<usize, BrickletRecvTimeoutError>

Writes characters to the RS232 interface. The characters can be binary data, ASCII or similar is not necessary.

The return value is the number of characters that were written.

See Rs232V2Bricklet::set_configuration for configuration possibilities regarding baud rate, parity and so on.

pub fn Rs232V2Bricklet::read(&self, length: u16) → Result<Vec<char>, BrickletRecvTimeoutError>

Returns up to length characters from receive buffer.

Instead of polling with this function, you can also use callbacks. But note that this function will return available data only when the read callback is disabled. See Rs232V2Bricklet::enable_read_callback and Rs232V2Bricklet::get_read_callback_receiver callback.

pub fn Rs232V2Bricklet::set_configuration(&self, baudrate: u32, parity: u8, stopbits: u8, wordlength: u8, flowcontrol: u8) → ConvertingReceiver<()>

Sets the configuration for the RS232 communication. Available options:

  • Baud rate between 100 and 2000000 baud.
  • Parity of none, odd or even.
  • Stop bits can be 1 or 2.
  • Word length of 5 to 8.
  • Flow control can be off, software or hardware.

The default is: 115200 baud, parity none, 1 stop bit, word length 8.

The following constants are available for this function:

  • RS232_V2_BRICKLET_PARITY_NONE = 0
  • RS232_V2_BRICKLET_PARITY_ODD = 1
  • RS232_V2_BRICKLET_PARITY_EVEN = 2
  • RS232_V2_BRICKLET_STOPBITS_1 = 1
  • RS232_V2_BRICKLET_STOPBITS_2 = 2
  • RS232_V2_BRICKLET_WORDLENGTH_5 = 5
  • RS232_V2_BRICKLET_WORDLENGTH_6 = 6
  • RS232_V2_BRICKLET_WORDLENGTH_7 = 7
  • RS232_V2_BRICKLET_WORDLENGTH_8 = 8
  • RS232_V2_BRICKLET_FLOWCONTROL_OFF = 0
  • RS232_V2_BRICKLET_FLOWCONTROL_SOFTWARE = 1
  • RS232_V2_BRICKLET_FLOWCONTROL_HARDWARE = 2
pub fn Rs232V2Bricklet::get_configuration(&self) → ConvertingReceiver<Configuration>

Returns the configuration as set by Rs232V2Bricklet::set_configuration.

The following constants are available for this function:

  • RS232_V2_BRICKLET_PARITY_NONE = 0
  • RS232_V2_BRICKLET_PARITY_ODD = 1
  • RS232_V2_BRICKLET_PARITY_EVEN = 2
  • RS232_V2_BRICKLET_STOPBITS_1 = 1
  • RS232_V2_BRICKLET_STOPBITS_2 = 2
  • RS232_V2_BRICKLET_WORDLENGTH_5 = 5
  • RS232_V2_BRICKLET_WORDLENGTH_6 = 6
  • RS232_V2_BRICKLET_WORDLENGTH_7 = 7
  • RS232_V2_BRICKLET_WORDLENGTH_8 = 8
  • RS232_V2_BRICKLET_FLOWCONTROL_OFF = 0
  • RS232_V2_BRICKLET_FLOWCONTROL_SOFTWARE = 1
  • RS232_V2_BRICKLET_FLOWCONTROL_HARDWARE = 2

Advanced Functions

pub fn Rs232V2Bricklet::set_buffer_config(&self, send_buffer_size: u16, receive_buffer_size: u16) → ConvertingReceiver<()>

Sets the send and receive buffer size in byte. In total the buffers have to be 10240 byte (10kb) in size, the minimum buffer size is 1024 byte (1kb) for each.

The current buffer content is lost if this function is called.

The send buffer holds data that is given by Rs232V2Bricklet::write and can not be written yet. The receive buffer holds data that is received through RS232 but could not yet be send to the user, either by Rs232V2Bricklet::read or through Rs232V2Bricklet::get_read_callback_receiver callback.

The default configuration is 5120 byte (5kb) per buffer.

pub fn Rs232V2Bricklet::get_buffer_config(&self) → ConvertingReceiver<BufferConfig>

Returns the buffer configuration as set by Rs232V2Bricklet::set_buffer_config.

pub fn Rs232V2Bricklet::get_buffer_status(&self) → ConvertingReceiver<BufferStatus>

Returns the currently used bytes for the send and received buffer.

See Rs232V2Bricklet::set_buffer_config for buffer size configuration.

pub fn Rs232V2Bricklet::get_error_count(&self) → ConvertingReceiver<ErrorCount>

Returns the current number of overrun and parity errors.

pub fn Rs232V2Bricklet::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 Rs232V2Bricklet::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 Rs232V2Bricklet::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 Rs232V2Bricklet::set_response_expected for the list of function ID constants available for this function.

pub fn Rs232V2Bricklet::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:

  • RS232_V2_BRICKLET_FUNCTION_ENABLE_READ_CALLBACK = 3
  • RS232_V2_BRICKLET_FUNCTION_DISABLE_READ_CALLBACK = 4
  • RS232_V2_BRICKLET_FUNCTION_SET_CONFIGURATION = 6
  • RS232_V2_BRICKLET_FUNCTION_SET_BUFFER_CONFIG = 8
  • RS232_V2_BRICKLET_FUNCTION_SET_WRITE_FIRMWARE_POINTER = 237
  • RS232_V2_BRICKLET_FUNCTION_SET_STATUS_LED_CONFIG = 239
  • RS232_V2_BRICKLET_FUNCTION_RESET = 243
  • RS232_V2_BRICKLET_FUNCTION_WRITE_UID = 248
pub fn Rs232V2Bricklet::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 Rs232V2Bricklet::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 Rs232V2Bricklet::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:

  • RS232_V2_BRICKLET_BOOTLOADER_MODE_BOOTLOADER = 0
  • RS232_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE = 1
  • RS232_V2_BRICKLET_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • RS232_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • RS232_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
  • RS232_V2_BRICKLET_BOOTLOADER_STATUS_OK = 0
  • RS232_V2_BRICKLET_BOOTLOADER_STATUS_INVALID_MODE = 1
  • RS232_V2_BRICKLET_BOOTLOADER_STATUS_NO_CHANGE = 2
  • RS232_V2_BRICKLET_BOOTLOADER_STATUS_ENTRY_FUNCTION_NOT_PRESENT = 3
  • RS232_V2_BRICKLET_BOOTLOADER_STATUS_DEVICE_IDENTIFIER_INCORRECT = 4
  • RS232_V2_BRICKLET_BOOTLOADER_STATUS_CRC_MISMATCH = 5
pub fn Rs232V2Bricklet::get_bootloader_mode(&self) → ConvertingReceiver<u8>

Returns the current bootloader mode, see Rs232V2Bricklet::set_bootloader_mode.

The following constants are available for this function:

  • RS232_V2_BRICKLET_BOOTLOADER_MODE_BOOTLOADER = 0
  • RS232_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE = 1
  • RS232_V2_BRICKLET_BOOTLOADER_MODE_BOOTLOADER_WAIT_FOR_REBOOT = 2
  • RS232_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_REBOOT = 3
  • RS232_V2_BRICKLET_BOOTLOADER_MODE_FIRMWARE_WAIT_FOR_ERASE_AND_REBOOT = 4
pub fn Rs232V2Bricklet::set_write_firmware_pointer(&self, pointer: u32) → ConvertingReceiver<()>

Sets the firmware pointer for Rs232V2Bricklet::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 Rs232V2Bricklet::write_firmware(&self, data: [u8; 64]) → ConvertingReceiver<u8>

Writes 64 Bytes of firmware at the position as written by Rs232V2Bricklet::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 Rs232V2Bricklet::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:

  • RS232_V2_BRICKLET_STATUS_LED_CONFIG_OFF = 0
  • RS232_V2_BRICKLET_STATUS_LED_CONFIG_ON = 1
  • RS232_V2_BRICKLET_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • RS232_V2_BRICKLET_STATUS_LED_CONFIG_SHOW_STATUS = 3
pub fn Rs232V2Bricklet::get_status_led_config(&self) → ConvertingReceiver<u8>

Returns the configuration as set by Rs232V2Bricklet::set_status_led_config

The following constants are available for this function:

  • RS232_V2_BRICKLET_STATUS_LED_CONFIG_OFF = 0
  • RS232_V2_BRICKLET_STATUS_LED_CONFIG_ON = 1
  • RS232_V2_BRICKLET_STATUS_LED_CONFIG_SHOW_HEARTBEAT = 2
  • RS232_V2_BRICKLET_STATUS_LED_CONFIG_SHOW_STATUS = 3
pub fn Rs232V2Bricklet::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 Rs232V2Bricklet::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 Rs232V2Bricklet::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 Rs232V2Bricklet::read_uid(&self) → ConvertingReceiver<u32>

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

pub fn Rs232V2Bricklet::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 Rs232V2Bricklet::enable_read_callback(&self) → ConvertingReceiver<()>

Enables the Rs232V2Bricklet::get_read_callback_receiver callback.

By default the callback is disabled.

pub fn Rs232V2Bricklet::disable_read_callback(&self) → ConvertingReceiver<()>

Disables the Rs232V2Bricklet::get_read_callback_receiver callback.

By default the callback is disabled.

pub fn Rs232V2Bricklet::is_read_callback_enabled(&self) → ConvertingReceiver<bool>

Returns true if the Rs232V2Bricklet::get_read_callback_receiver callback is enabled, false otherwise.

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 Rs232V2Bricklet::get_read_callback_receiver(&self) → ConvertingHighLevelCallbackReceiver<char, ReadResult, ReadLowLevelEvent>

Receivers created with this function receive Read events.

This callback is called if new data is available.

To enable this callback, use Rs232V2Bricklet::enable_read_callback.

pub fn Rs232V2Bricklet::get_error_count_callback_receiver(&self) → ConvertingCallbackReceiver<ErrorCountEvent>

Receivers created with this function receive Error Count events.

This callback is called if a new error occurs. It returns the current overrun and parity error count.

Constants

Rs232V2Bricklet::DEVICE_IDENTIFIER

This constant is used to identify a RS232 Bricklet 2.0.

The Rs232V2Bricklet::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.

Rs232V2Bricklet::DEVICE_DISPLAY_NAME

This constant represents the human readable name of a RS232 Bricklet 2.0.