Struct ModbusRtuClient 

pub struct ModbusRtuClient { /* private fields */ }

Modbus RTU client for serial communication

Implements async Modbus RTU protocol over RS-232/RS-485 serial ports.

Example

use oxirs_modbus::protocol::rtu::ModbusRtuClient;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let mut client = ModbusRtuClient::open("/dev/ttyUSB0", 9600, 1)?;
    let registers = client.read_holding_registers(0, 10).await?;
    println!("Registers: {:?}", registers);
    Ok(())
}

Implementations

impl ModbusRtuClient

pub fn open(port: &str, baud_rate: u32, unit_id: u8) -> ModbusResult<Self>

Open a Modbus RTU connection

Arguments

• port - Serial port path (e.g., “/dev/ttyUSB0”, “COM1”)
• baud_rate - Baud rate (typically 9600, 19200, 38400, 57600, or 115200)
• unit_id - Modbus unit/slave ID (1-247)

Returns

A connected ModbusRtuClient instance

pub fn open_with_settings( port: &str, baud_rate: u32, unit_id: u8, data_bits: DataBits, parity: Parity, stop_bits: StopBits, ) -> ModbusResult<Self>

Open with custom serial settings

Arguments

• port - Serial port path
• baud_rate - Baud rate
• unit_id - Modbus unit ID
• data_bits - Number of data bits
• parity - Parity setting
• stop_bits - Stop bits

pub fn set_timeout(&mut self, timeout: Duration)

Set response timeout

pub async fn read_holding_registers( &mut self, start_address: u16, count: u16, ) -> ModbusResult<Vec<u16>>

Read holding registers (function code 0x03)

Arguments

• start_address - Starting register address (0-based)
• count - Number of registers to read (1-125)

Returns

Vector of register values

pub async fn read_input_registers( &mut self, start_address: u16, count: u16, ) -> ModbusResult<Vec<u16>>

Read input registers (function code 0x04)

Arguments

• start_address - Starting register address (0-based)
• count - Number of registers to read (1-125)

Returns

Vector of register values

pub async fn write_single_register( &mut self, address: u16, value: u16, ) -> ModbusResult<()>

Write a single register (function code 0x06)

Arguments

• address - Register address
• value - Value to write

pub async fn read_coils( &mut self, start_address: u16, count: u16, ) -> ModbusResult<Vec<bool>>

Read coils (function code 0x01)

Arguments

• start_address - Starting coil address (0-based)
• count - Number of coils to read (1-2000)

Returns

Vector of coil states (true = ON, false = OFF)

pub async fn read_discrete_inputs( &mut self, start_address: u16, count: u16, ) -> ModbusResult<Vec<bool>>

Read discrete inputs (function code 0x02)

Arguments

• start_address - Starting address (0-based)
• count - Number of inputs to read (1-2000)

Returns

Vector of input states (true = ON, false = OFF)