Fieldset

A fieldset is a collection of fields that make up the data of a register, command input or command output.

Each fieldset defines a type where each of the fields are accessible through operations with the names of the fields.

Note

As a user you should not have to construct your fieldsets manually in normal use. But it’s available to you for special cases.

Example usage:

use device_driver::Fieldset;

let mut reg = MyFieldSet::ZERO;
reg.set_foo(1234);
let foo = reg.foo();

Fieldsets also implement all bitwise operators for easier manipulation. These operations are done on all underlying bits, even ones that are not part of a field.

There’s also an Into and From implementation to byte arrays of the same size of the fieldset. All possible bitpatterns are legal.

Example usage:

let all_ones = !MyFieldSet::from([0x00, 0x00]);
let lowest_byte_set = MyFieldSet::from([0xFF, 0x00]);
let lowest_byte_inverted = all_ones ^ lowest_byte_set;

Example

/// doc comment line
fieldset Example {
    size-bytes: 8,
    byte-order: LE,
    bit-overlap: allow,
    default-access: RW,

    field node,
}

Table

Long properties

These properties are specified in the node body.

size-bytes

The size of the fieldset in number of bytes.

// number
size-bytes: 8

Info

• required: yes
• multiple allowed: no
• supports doc comments: no

byte-order

The byte order of the fieldset data.

// byte order
byte-order: LE

Info

• required: no
• multiple allowed: no
• supports doc comments: no

bit-overlap

Allows fields to overlap. This is not allowed by default to prevent copy-paste mistakes.

// allow
bit-overlap: allow

Info

• required: no
• multiple allowed: no
• supports doc comments: no

default-access

When set, all subobjects use this value as their access value (unless overridden) and don’t require an access specifier anymore

// access specifier
default-access: RW

Info

• required: no
• multiple allowed: no
• supports doc comments: no

Possible subnodes

Subnodes of the following types are allowed in the node body.

• field