Struct DataModel

Source

pub struct DataModel<const L: usize, T: Copy> { /* private fields */ }

Expand description

A data model for accessing values stored at unique 16-bit addresses.

§Examples

use modbus_rtu::slave::{DataModel, DataStructure};
 
// Define data structure first.
const DATA_STRUCTURE: DataStructure<4> = DataStructure::new([
    0x0001,
    0x0002,
    0x1234,
    0x5678,
]);
 
// And create a new data model instance with initial value array.
let data_model = DataModel::new(&DATA_STRUCTURE, [0; 4]);

Implementations§

Source §

impl<const L: usize, T: Copy> DataModel<L, T>

Source

pub fn new( structure: &'static DataStructure<L>, initial_values: [T; L], ) -> DataModel<L, T>

Creates and initializes a new data model using the given data structure.

§Arguments

structure: A reference to the constant data structure.
initial_values: The initial values to populate the data model.

§Returns

A new DataModel instance initialized with the provided structure and values.

§Examples

use modbus_rtu::slave::{DataModel, DataStructure};
 
const STRUCTURE: DataStructure<5> = DataStructure::new([
    0x0000,
    0x0001,
    0x0002,
    0x1234,
    0x5678,
]);
 
let data_model = DataModel::new(&STRUCTURE, [0; 5]);

Source

pub const fn get_value(&self, address: u16) -> T

Retrieves a value from the data model by using an address defined in the associated data structure.

This method uses the address defined in the data structure to access the corresponding value stored within the data model.

§Arguments

address: The address of the value to retrieve. Only addresses defined in the data structure are allowed.

§Returns

The value stored at the specified address.

§Examples

use modbus_rtu::slave::{DataModel, DataStructure};
 
const STRUCTURE: DataStructure<5> = DataStructure::new([
    0x0000,
    0x0001,
    0x0002,
    0x1234,
    0x5678,
]);
 
let data_model = DataModel::new(&STRUCTURE, [0; 5]);
 
assert_eq!(data_model.get_value(0x0001), 0);

The code below will panic at compile time.

// Will panic!!
let value = data_model.get_value(0x0003);

§Panics

…

Source

pub fn find_value(&self, address: u16) -> Option<T>

Retrieves a value from the data model using a given address, if it exists in the structure.

Unlike get_value, this method returns None instead of panicking if the address is not part of the structure. This makes it suitable for use with dynamic or external input.

§Arguments

address: The address of the value to look up. The address may or may not be defined in the structure.

§Returns

An Option<T> containing the value if the address is found, or None if it is not.

§Examples

use modbus_rtu::slave::{DataModel, DataStructure};

const STRUCTURE: DataStructure<5> = DataStructure::new([
    0x0000,
    0x0001,
    0x0002,
    0x1234,
    0x5678,
]);

let data_model = DataModel::new(&STRUCTURE, [10, 20, 30, 40, 50]);

assert_eq!(data_model.find_value(0x0002), Some(30));
assert_eq!(data_model.find_value(0x9999), None);

Source

pub fn set_value(&mut self, index: usize, value: T)

Sets a value in the data model at the specified index.

This function assumes the index is already validated and corresponds to a valid entry in the model.

§Args

index: The index at which to set the value. This must be valid, as obtained from get_index.
value: The value to be set at the specified index.

§Examples

// This is find.
let i = data_model.get_index(0x0000);
data_model.set_value(i, 5);
 
// This is fine too.
if let Some(i) = data_model.find_index(0x0008) {
    data_model.set_value(i, 5);
}
 
// But this might panic.
data_model.set_value(3, 5);

§Panics

Panics if the index is out of bounds.

Source

pub const fn get_index(&self, address: u16) -> usize

Retrieves the internal index for a given address defined in the data structure.

This is useful when you want to perform index-based operations on the values array.

§Args

address: The address whose index should be retrieved. Must be present in the structure.

§Returns

The index corresponding to the given address.

§Panics

Panics at compile time if the address is not found in the structure.

Source

pub fn find_index(&self, address: u16) -> Option<usize>

Attempts to find the index for a given address, if it exists in the data structure.

This method is safe to use with dynamic or externally provided addresses.

§Args

address: The address to search for.

§Returns

Some(index) if the address is present, or None otherwise.

Source

pub fn is_empty(&self) -> bool

Checks whether the data model is empty.

This returns true if the data model contains no entries, which occurs when its length L is zero.

§Returns

true if the data model is empty, false otherwise.

§Examples

use modbus_rtu::slave::DataModel;

let empty_model = DataModel::<0, u16>::empty();
assert!(empty_model.is_empty());

Source §

impl<T: Copy> DataModel<0, T>

Source

pub fn empty() -> DataModel<0, T>

Creates and returns an empty data model with no stored values.

This is useful when a data model is required but no data is needed or used.

§Returns

An empty DataModel instance with no associated data.

§Examples

use modbus_rtu::slave::{ModbusSlave, DataModel};

let holding_registers = DataModel::empty();
let input_registers = DataModel::empty();
 
// Create modbus slave instance with zero registers
let modbus_slave = ModbusSlave::new(0x01, holding_registers, input_registers);