Struct Address 

pub struct Address(/* private fields */);

Represents a validated Modbus device address, used for RTU communication over RS485.

Valid addresses are in the range 1 to 247 (inclusive). Use Address::try_from to create an instance from a u8. Provides constants and methods for reading/writing the device address itself via Modbus commands.

Implementations

impl Address

pub const ADDRESS: u16 = 254u16

The Modbus register address used to read or write the device’s own Modbus address.

Use Modbus function 0x03 (Read Holding Registers) to read (requires addressing the device with its current address or the broadcast address). Use function 0x06 (Write Single Register) to change the address (also requires addressing the device with its current address).

pub const QUANTITY: u16 = 1u16

The number of registers to read when reading the device address.

pub const MIN: u8 = 1u8

The minimum valid assignable Modbus device address (inclusive).

pub const MAX: u8 = 247u8

The maximum valid assignable Modbus device address (inclusive).

pub const BROADCAST: Address

The Modbus broadcast address (0xFF or 255).

Can be used for reading the device address when it’s unknown. This address cannot be assigned to a device as its permanent address.

pub fn decode_from_holding_registers(words: &[Word]) -> Result<Self, Error>

Decodes the device Address from a Modbus holding register value read from the device.

Expects words to contain the single register value read from the device address configuration register (Address::ADDRESS). It validates that the decoded address is within the assignable range (Address::MIN..=Address::MAX).

Arguments

• words: A slice containing the Word value read from the device address register. Expected to have length 1.

Returns

An Address struct containing the decoded and validated value, or an Error if decoding fails.

Errors

• Error::UnexpectedDataLength: if words does not contain exactly one element.
• Error::InvalidData: if the upper byte of the register value is non-zero.

pub fn encode_for_write_register(&self) -> Word

Encodes the Address into its Word representation for writing to the Modbus register.

Returns

The Word representation of the address.

Methods from Deref<Target = u8>

pub const MIN: u8 = 0u8

pub const MAX: u8 = 255u8

pub const BITS: u32 = 8u32

pub fn is_ascii(&self) -> bool

Checks if the value is within the ASCII range.

Examples

let ascii = 97u8;
let non_ascii = 150u8;

assert!(ascii.is_ascii());
assert!(!non_ascii.is_ascii());

pub fn as_ascii(&self) -> Option<AsciiChar>

🔬This is a nightly-only experimental API. (ascii_char)

If the value of this byte is within the ASCII range, returns it as an ASCII character. Otherwise, returns None.

pub unsafe fn as_ascii_unchecked(&self) -> AsciiChar

🔬This is a nightly-only experimental API. (ascii_char)

Converts this byte to an ASCII character, without checking whether or not it’s valid.

Safety

This byte must be valid ASCII, or else this is UB.

pub fn to_ascii_uppercase(&self) -> u8

Makes a copy of the value in its ASCII upper case equivalent.

ASCII letters ‘a’ to ‘z’ are mapped to ‘A’ to ‘Z’, but non-ASCII letters are unchanged.

To uppercase the value in-place, use make_ascii_uppercase.

Examples

let lowercase_a = 97u8;

assert_eq!(65, lowercase_a.to_ascii_uppercase());

pub fn to_ascii_lowercase(&self) -> u8

Makes a copy of the value in its ASCII lower case equivalent.

ASCII letters ‘A’ to ‘Z’ are mapped to ‘a’ to ‘z’, but non-ASCII letters are unchanged.

To lowercase the value in-place, use make_ascii_lowercase.

Examples

let uppercase_a = 65u8;

assert_eq!(97, uppercase_a.to_ascii_lowercase());

pub fn eq_ignore_ascii_case(&self, other: &u8) -> bool

Checks that two values are an ASCII case-insensitive match.

This is equivalent to to_ascii_lowercase(a) == to_ascii_lowercase(b).

Examples

let lowercase_a = 97u8;
let uppercase_a = 65u8;

assert!(lowercase_a.eq_ignore_ascii_case(&uppercase_a));

pub fn is_ascii_alphabetic(&self) -> bool

Checks if the value is an ASCII alphabetic character:

• U+0041 ‘A’ ..= U+005A ‘Z’, or
• U+0061 ‘a’ ..= U+007A ‘z’.

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(uppercase_a.is_ascii_alphabetic());
assert!(uppercase_g.is_ascii_alphabetic());
assert!(a.is_ascii_alphabetic());
assert!(g.is_ascii_alphabetic());
assert!(!zero.is_ascii_alphabetic());
assert!(!percent.is_ascii_alphabetic());
assert!(!space.is_ascii_alphabetic());
assert!(!lf.is_ascii_alphabetic());
assert!(!esc.is_ascii_alphabetic());

pub fn is_ascii_uppercase(&self) -> bool

Checks if the value is an ASCII uppercase character: U+0041 ‘A’ ..= U+005A ‘Z’.

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(uppercase_a.is_ascii_uppercase());
assert!(uppercase_g.is_ascii_uppercase());
assert!(!a.is_ascii_uppercase());
assert!(!g.is_ascii_uppercase());
assert!(!zero.is_ascii_uppercase());
assert!(!percent.is_ascii_uppercase());
assert!(!space.is_ascii_uppercase());
assert!(!lf.is_ascii_uppercase());
assert!(!esc.is_ascii_uppercase());

pub fn is_ascii_lowercase(&self) -> bool

Checks if the value is an ASCII lowercase character: U+0061 ‘a’ ..= U+007A ‘z’.

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(!uppercase_a.is_ascii_lowercase());
assert!(!uppercase_g.is_ascii_lowercase());
assert!(a.is_ascii_lowercase());
assert!(g.is_ascii_lowercase());
assert!(!zero.is_ascii_lowercase());
assert!(!percent.is_ascii_lowercase());
assert!(!space.is_ascii_lowercase());
assert!(!lf.is_ascii_lowercase());
assert!(!esc.is_ascii_lowercase());

pub fn is_ascii_alphanumeric(&self) -> bool

Checks if the value is an ASCII alphanumeric character:

• U+0041 ‘A’ ..= U+005A ‘Z’, or
• U+0061 ‘a’ ..= U+007A ‘z’, or
• U+0030 ‘0’ ..= U+0039 ‘9’.

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(uppercase_a.is_ascii_alphanumeric());
assert!(uppercase_g.is_ascii_alphanumeric());
assert!(a.is_ascii_alphanumeric());
assert!(g.is_ascii_alphanumeric());
assert!(zero.is_ascii_alphanumeric());
assert!(!percent.is_ascii_alphanumeric());
assert!(!space.is_ascii_alphanumeric());
assert!(!lf.is_ascii_alphanumeric());
assert!(!esc.is_ascii_alphanumeric());

pub fn is_ascii_digit(&self) -> bool

Checks if the value is an ASCII decimal digit: U+0030 ‘0’ ..= U+0039 ‘9’.

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(!uppercase_a.is_ascii_digit());
assert!(!uppercase_g.is_ascii_digit());
assert!(!a.is_ascii_digit());
assert!(!g.is_ascii_digit());
assert!(zero.is_ascii_digit());
assert!(!percent.is_ascii_digit());
assert!(!space.is_ascii_digit());
assert!(!lf.is_ascii_digit());
assert!(!esc.is_ascii_digit());

pub fn is_ascii_octdigit(&self) -> bool

🔬This is a nightly-only experimental API. (is_ascii_octdigit)

Checks if the value is an ASCII octal digit: U+0030 ‘0’ ..= U+0037 ‘7’.

Examples

#![feature(is_ascii_octdigit)]

let uppercase_a = b'A';
let a = b'a';
let zero = b'0';
let seven = b'7';
let nine = b'9';
let percent = b'%';
let lf = b'\n';

assert!(!uppercase_a.is_ascii_octdigit());
assert!(!a.is_ascii_octdigit());
assert!(zero.is_ascii_octdigit());
assert!(seven.is_ascii_octdigit());
assert!(!nine.is_ascii_octdigit());
assert!(!percent.is_ascii_octdigit());
assert!(!lf.is_ascii_octdigit());

pub fn is_ascii_hexdigit(&self) -> bool

Checks if the value is an ASCII hexadecimal digit:

• U+0030 ‘0’ ..= U+0039 ‘9’, or
• U+0041 ‘A’ ..= U+0046 ‘F’, or
• U+0061 ‘a’ ..= U+0066 ‘f’.

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(uppercase_a.is_ascii_hexdigit());
assert!(!uppercase_g.is_ascii_hexdigit());
assert!(a.is_ascii_hexdigit());
assert!(!g.is_ascii_hexdigit());
assert!(zero.is_ascii_hexdigit());
assert!(!percent.is_ascii_hexdigit());
assert!(!space.is_ascii_hexdigit());
assert!(!lf.is_ascii_hexdigit());
assert!(!esc.is_ascii_hexdigit());

pub fn is_ascii_punctuation(&self) -> bool

Checks if the value is an ASCII punctuation character:

• U+0021 ..= U+002F ! " # $ % & ' ( ) * + , - . /, or
• U+003A ..= U+0040 : ; < = > ? @, or
• U+005B ..= U+0060 [ \ ] ^ _ `, or
• U+007B ..= U+007E { | } ~

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(!uppercase_a.is_ascii_punctuation());
assert!(!uppercase_g.is_ascii_punctuation());
assert!(!a.is_ascii_punctuation());
assert!(!g.is_ascii_punctuation());
assert!(!zero.is_ascii_punctuation());
assert!(percent.is_ascii_punctuation());
assert!(!space.is_ascii_punctuation());
assert!(!lf.is_ascii_punctuation());
assert!(!esc.is_ascii_punctuation());

pub fn is_ascii_graphic(&self) -> bool

Checks if the value is an ASCII graphic character: U+0021 ‘!’ ..= U+007E ‘~’.

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(uppercase_a.is_ascii_graphic());
assert!(uppercase_g.is_ascii_graphic());
assert!(a.is_ascii_graphic());
assert!(g.is_ascii_graphic());
assert!(zero.is_ascii_graphic());
assert!(percent.is_ascii_graphic());
assert!(!space.is_ascii_graphic());
assert!(!lf.is_ascii_graphic());
assert!(!esc.is_ascii_graphic());

pub fn is_ascii_whitespace(&self) -> bool

Checks if the value is an ASCII whitespace character: U+0020 SPACE, U+0009 HORIZONTAL TAB, U+000A LINE FEED, U+000C FORM FEED, or U+000D CARRIAGE RETURN.

Rust uses the WhatWG Infra Standard’s definition of ASCII whitespace. There are several other definitions in wide use. For instance, the POSIX locale includes U+000B VERTICAL TAB as well as all the above characters, but—from the very same specification—the default rule for “field splitting” in the Bourne shell considers only SPACE, HORIZONTAL TAB, and LINE FEED as whitespace.

If you are writing a program that will process an existing file format, check what that format’s definition of whitespace is before using this function.

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(!uppercase_a.is_ascii_whitespace());
assert!(!uppercase_g.is_ascii_whitespace());
assert!(!a.is_ascii_whitespace());
assert!(!g.is_ascii_whitespace());
assert!(!zero.is_ascii_whitespace());
assert!(!percent.is_ascii_whitespace());
assert!(space.is_ascii_whitespace());
assert!(lf.is_ascii_whitespace());
assert!(!esc.is_ascii_whitespace());

pub fn is_ascii_control(&self) -> bool

Checks if the value is an ASCII control character: U+0000 NUL ..= U+001F UNIT SEPARATOR, or U+007F DELETE. Note that most ASCII whitespace characters are control characters, but SPACE is not.

Examples

let uppercase_a = b'A';
let uppercase_g = b'G';
let a = b'a';
let g = b'g';
let zero = b'0';
let percent = b'%';
let space = b' ';
let lf = b'\n';
let esc = b'\x1b';

assert!(!uppercase_a.is_ascii_control());
assert!(!uppercase_g.is_ascii_control());
assert!(!a.is_ascii_control());
assert!(!g.is_ascii_control());
assert!(!zero.is_ascii_control());
assert!(!percent.is_ascii_control());
assert!(!space.is_ascii_control());
assert!(lf.is_ascii_control());
assert!(esc.is_ascii_control());

Trait Implementations

impl Clone for Address

fn clone(&self) -> Address

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Address

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Address

fn default() -> Self

Returns the factory default Modbus address.

impl Deref for Address

Allows direct access to the underlying u8 address value.

type Target = u8

The resulting type after dereferencing.

fn deref(&self) -> &Self::Target

Dereferences the value.

impl<'de> Deserialize<'de> for Address

Available on crate feature serde only.

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for Address

Provides a hexadecimal string representation (e.g., “0x01”, “0xf7”).

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Ord for Address

fn cmp(&self, other: &Address) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for Address

fn eq(&self, other: &Address) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Address

fn partial_cmp(&self, other: &Address) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl Serialize for Address

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl TryFrom<u8> for Address

fn try_from(value: u8) -> Result<Self, Self::Error>

Attempts to create an Address from a u8 value, validating its assignable range [Address::MIN, Address::MAX].

Arguments

• value: The Modbus address to validate.

Returns

• Ok(Address): If the value is within the valid assignable range [Address::MIN, Address::MAX].
• Err(ErrorAddressOutOfRange): If the value is outside the valid assignable range (e.g., 0 or > 247).

Example

assert!(matches!(Address::try_from(0), Err(ErrorAddressOutOfRange(_))));
assert!(Address::try_from(1).is_ok());
assert!(Address::try_from(247).is_ok());
assert_eq!(Address::try_from(248).unwrap_err(), ErrorAddressOutOfRange(248));
assert!(matches!(Address::try_from(255), Err(ErrorAddressOutOfRange(_)))); // Broadcast address is not valid for TryFrom

type Error = ErrorAddressOutOfRange

The type returned in the event of a conversion error.

impl Copy for Address

impl Eq for Address

impl StructuralPartialEq for Address