Struct ClientSession 

pub struct ClientSession<'b, S, TX, TS, D = NoDelay> { /* private fields */ }

An active Modbus RTU → TCP client session.

Returned by Client::connect. Mutably borrows the client for its lifetime, preventing a second session from being opened until this one is finished.

Drive the session by calling next in a loop.

Implementations

impl<'b, S, TX, TS, D> ClientSession<'b, S, TX, TS, D>

pub fn into_stream(self) -> TS

Consumes the session and returns the underlying TCP stream.

Examples

let tcp_stream = session.into_stream();

impl<S, TX, TS> ClientSession<'_, S, TX, TS, NoDelay>

where S: Read + Write, TX: OutputPin, TS: Read + Write,

pub async fn next( &mut self, ) -> Result<BridgeEvent, BridgeError<S::Error, TS::Error>>

Drives one complete Modbus request/response cycle asynchronously.

Reads an RTU request from the serial port, forwards it to the upstream Modbus TCP server, and returns the response to the RTU master.

Errors

Returns BridgeError::RtuClosed when the RTU master closes the connection cleanly.

impl<S, TX, TS, D> ClientSession<'_, S, TX, TS, D>

where S: Read + Write, TX: OutputPin, TS: Read + Write, D: DelayNs,

pub async fn next( &mut self, ) -> Result<BridgeEvent, BridgeError<S::Error, TS::Error>>

Drives one complete Modbus request/response cycle asynchronously, with timeouts.

Reads an RTU request from the serial port, forwards it to the upstream Modbus TCP server, and returns the response to the RTU master. Applies rtu_timeout_ms around the RTU listen and tcp_timeout_ms around the TCP response.

Errors

• BridgeError::RtuClosed — RTU master sent EOF (normal disconnect).
• BridgeError::RtuIo — Serial port I/O error.
• BridgeError::RtuCrcMismatch — RTU request failed CRC-16 check.
• BridgeError::TcpClosed — Upstream TCP server closed the connection.
• BridgeError::TcpIo — TCP stream I/O error.
• BridgeError::BufferOverflow — Frame exceeded internal buffer capacity.
• BridgeError::Timeout — An I/O operation did not complete within the configured deadline.