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| <title>Field - ARM Machine Readable Schema - 2.7.1</title> |
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| <div class="col-md-6 pull-left"><h1>AARCHMRS Schema <small>2.7.1</small></h1></div> |
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| <h2> |
| <span class="title-namespace">Fields.</span><span class=" title-type">Field</span> |
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| <!-- if oneOf is set, then type is ignored --> |
| <span class="type">object</span> |
| </h2> |
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| <div class="static-markdown"><p>A Field defines a named field with the meaning definition of each of its known values.</p></div> |
| </div> |
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| <div class="row"> |
| |
| <div> |
| <!-- A simple object --> |
| <h3 class="type">object</h3> |
| |
| <table class="table table-hover properties"> |
| <thead> |
| <tr> |
| <th class="col-md-4">Properties</th> |
| <th class="col-md-4">Type</th> |
| <th class="col-md-4">Description</th> |
| </tr> |
| </thead> |
| <tbody> |
| |
| <!-- properties --> |
| |
| |
| <tr id="/properties/_meta" class="property"> |
| <th class="col-md-4"> |
| <a href="#/properties/_meta">_meta</a> |
| </th> |
| <td class="col-md-4"> |
| <a href="../Meta_schema.html" class="schema_link">Meta</a> |
| </td> |
| <td class="col-md-4"> |
| |
| <div> |
| See |
| <a href="../Meta_schema.html" class="schema_link">Meta</a> |
| for more information. |
| </div> |
| |
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| |
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| </td> |
| </tr> |
| |
| <tr id="/properties/_type" class="property"> |
| <th class="col-md-4"> |
| <a href="#/properties/_type">_type</a> |
| </th> |
| <td class="col-md-4"> |
| </td> |
| <td class="col-md-4"> |
| <dl> |
| <dt>Enum</dt> |
| <dd> |
| <code>Fields.Field</code> |
| </dd> |
| </dl> |
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| </td> |
| </tr> |
| |
| <tr id="/properties/access" class="property"> |
| <th class="col-md-4"> |
| <a href="#/properties/access">access</a> |
| </th> |
| <td class="col-md-4"> |
| <a href="../Traits/HasFieldAccess_schema.html#/definitions/access" class="schema_link">Traits.HasFieldAccess</a> |
| </td> |
| <td class="col-md-4"> |
| |
| <div> |
| See |
| <a href="../Traits/HasFieldAccess_schema.html#/definitions/access" class="schema_link">definitions.access</a> in |
| <a href="../Traits/HasFieldAccess_schema.html#/definitions/access" class="schema_link">Traits.HasFieldAccess</a> |
| for more information. |
| </div> |
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| </td> |
| </tr> |
| |
| <tr id="/properties/description" class="property"> |
| <th class="col-md-4"> |
| <a href="#/properties/description">description</a> |
| </th> |
| <td class="col-md-4"> |
| <a href="../Traits/HasDescription_schema.html#/definitions/description" class="schema_link">Traits.HasDescription</a> |
| </td> |
| <td class="col-md-4"> |
| <div><p>Provides an architectural description of this field.</p> |
| <p>You can use a dictionary that contains <code>before</code> and <code>after</code> keys, where:</p> |
| <ul> |
| <li>The <code>before</code> key is used to define architectural information that should be rendered before the values are represented.</li> |
| <li>The <code>after</code> key is used to define architectural information that should be rendered description after the values are represented.</li> |
| </ul> |
| <p>If the property value is of type <code>string</code>, this behaves as having a description with just the <em>before</em> key, |
| <code>before</code> and <code>after</code> have no architectural significance, this is just for rendering.</p></div> |
| |
| <div> |
| See |
| <a href="../Traits/HasDescription_schema.html#/definitions/description" class="schema_link">definitions.description</a> in |
| <a href="../Traits/HasDescription_schema.html#/definitions/description" class="schema_link">Traits.HasDescription</a> |
| for more information. |
| </div> |
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| </td> |
| </tr> |
| |
| <tr id="/properties/display" class="property"> |
| <th class="col-md-4 deprecated"> |
| <a href="#/properties/display">display</a> |
| </th> |
| <td class="col-md-4"> |
| <ul class="inline list-type"> |
| <li class="inline type">string</li> |
| <li class="inline type">null</li> |
| </ul> |
| </td> |
| <td class="col-md-4"> |
| <dl> |
| <dt>Deprecated</dt> |
| <dd>this property is deprecated and should not be used.</dd> |
| </dl> |
| <div><p>The display name of the field.</p> |
| <p>When null the <code>name</code> property is used as the display name.</p> |
| <p>Some architectural fields use this property, it is preferred to use the <code>name</code> property instead.</p></div> |
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| </td> |
| </tr> |
| |
| <tr id="/properties/name" class="property"> |
| <th class="col-md-4"> |
| <a href="#/properties/name">name<sup>◊</sup></a> |
| </th> |
| <td class="col-md-4"> |
| <ul class="inline list-type"> |
| <li class="inline type">string</li> |
| <li class="inline type">null</li> |
| </ul> |
| </td> |
| <td class="col-md-4"> |
| <div><p>The canonical name of the field. The name must be unique within this fieldset.</p></div> |
| |
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| </td> |
| </tr> |
| |
| <tr id="/properties/rangeset" class="property"> |
| <th class="col-md-4"> |
| <a href="#/properties/rangeset">rangeset<sup>◊</sup></a> |
| </th> |
| <td class="col-md-4"> |
| <a href="../Rangeset_schema.html" class="schema_link">Rangeset</a> |
| </td> |
| <td class="col-md-4"> |
| <div><p>A rangeset indicates the location this field appears in it's parent.</p> |
| <ul> |
| <li><code>0</code>: This field appears at the 0th location.</li> |
| <li><code>3:0</code>: This field is a 4 bit field spanning from the 3rd most significant bit (msb) to the 0th least significant bit (lsb) of it's parent.</li> |
| <li><code>5, 3:2, 0</code>: This field's msb is at 5th bit and lsb is at the 0th bit, with 4th bit and 1st bit not being a part of this field.</li> |
| </ul> |
| <p>The width of the rangeset represents the width of this field.</p></div> |
| |
| <div> |
| See |
| <a href="../Rangeset_schema.html" class="schema_link">Rangeset</a> |
| for more information. |
| </div> |
| |
| |
| |
| |
| </td> |
| </tr> |
| |
| <tr id="/properties/resets" class="property"> |
| <th class="col-md-4"> |
| <a href="#/properties/resets">resets</a> |
| </th> |
| <td class="col-md-4"> |
| <a href="../FieldResets_schema.html" class="schema_link">FieldResets</a> |
| </td> |
| <td class="col-md-4"> |
| <div><p>The reset value that applies to this field</p></div> |
| |
| <div> |
| See |
| <a href="../FieldResets_schema.html" class="schema_link">FieldResets</a> |
| for more information. |
| </div> |
| |
| |
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| </td> |
| </tr> |
| |
| <tr id="/properties/values" class="property"> |
| <th class="col-md-4"> |
| <a href="#/properties/values">values</a> |
| </th> |
| <td class="col-md-4"> |
| <a href="../Valuesets/ValuesetAbstract_schema.html#/definitions/children" class="schema_link">Valuesets.ValuesetAbstract</a> |
| </td> |
| <td class="col-md-4"> |
| <div><p>A set of <strong>Value</strong> objects. Each object indicates one of the valid values that may be present in this field, along with a textual description of its meaning.</p></div> |
| |
| <div> |
| See |
| <a href="../Valuesets/ValuesetAbstract_schema.html#/definitions/children" class="schema_link">definitions.children</a> in |
| <a href="../Valuesets/ValuesetAbstract_schema.html#/definitions/children" class="schema_link">Valuesets.ValuesetAbstract</a> |
| for more information. |
| </div> |
| |
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| </td> |
| </tr> |
| |
| <tr id="/properties/volatile" class="property"> |
| <th class="col-md-4"> |
| <a href="#/properties/volatile">volatile</a> |
| </th> |
| <td class="col-md-4"> |
| <ul class="inline list-type"> |
| <li class="inline type">boolean</li> |
| </ul> |
| </td> |
| <td class="col-md-4"> |
| <div><p>The volatile property indicates whether a field's value may change between different accesses, even if it does not appear to be modified. In general, it means that the field's value might be updated by the hardware.</p> |
| <p>For Example:</p> |
| <ul> |
| <li>A status register field changing value.</li> |
| <li>A counter incrementing.</li> |
| </ul></div> |
| <div> |
| <b>Default</b> |
| <pre class="schema-json"><code class="language-json">false</code></pre> |
| </div> |
| |
| |
| |
| </td> |
| </tr> |
| |
| |
| <!-- patternProperties --> |
| |
| <!-- object property attributes --> |
| <tr> |
| <td colspan="3"> |
| <dl> |
| <dt>Additional Properties</dt> |
| <dd>Not Allowed</dd> |
| </dl> |
| </td> |
| </tr> |
| |
| <tr> |
| <td colspan="3"> |
| <dl> |
| <dt>◊ Required</dt> |
| <dd>Properties marked with ◊ are required properties.</dd> |
| </dl> |
| </td> |
| </tr> |
| </tbody> |
| </table> |
| |
| |
| |
| |
| <!-- array, and it has described items --> |
| </div> |
| |
| |
| <h5>Examples</h5> |
| <div> |
| <pre class="schema-json"><code class="language-json">{ |
| "_type": "Fields.Field", |
| "name": "F1", |
| "rangeset": [ |
| { |
| "_type": "Range", |
| "start": 2, |
| "width": 4 |
| } |
| ], |
| "description": { |
| "_type": "Description", |
| "before": "A field in a register called F1", |
| "after": "All other values are reserved" |
| }, |
| "values": { |
| "_type": "Valuesets.Values", |
| "values": [ |
| { |
| "_type": "Values.Value", |
| "meaning": "First value", |
| "value": "'00'" |
| }, |
| { |
| "_type": "Values.Value", |
| "meaning": "Second value", |
| "value": "'10'" |
| }, |
| { |
| "_type": "Values.Value", |
| "meaning": "Third value", |
| "value": "'01'" |
| } |
| ] |
| }, |
| "resets": { |
| "_type": "FieldResets", |
| "domains": { |
| "cold": { |
| "_type": "Values.Value", |
| "value": "'00'", |
| "meaning": "The reset value, which resets to First value" |
| } |
| } |
| }, |
| "volatile": false |
| }</code></pre> |
| </div> |
| |
| |
| |
| |
| </div> |
| |
| <div class="row schema"> |
| <h3>Schema <small><a href="http://json-schema.org/draft-04/schema#">http://json-schema.org/draft-04/schema#</a></small></h3> |
| <pre class="schema-json"><code class="language-json">{ |
| "info": [ |
| "A Field defines a named field with the meaning definition of each of its known values." |
| ], |
| "properties": { |
| "_meta": { |
| "$ref": "../Meta.json" |
| }, |
| "_type": { |
| "enum": [ |
| "Fields.Field" |
| ] |
| }, |
| "access": { |
| "$ref": "../Traits/HasFieldAccess.json#/definitions/access" |
| }, |
| "description": { |
| "$ref": "../Traits/HasDescription.json#/definitions/description", |
| "info": [ |
| "Provides an architectural description of this field.", |
| "You can use a dictionary that contains `before` and `after` keys, where:", |
| [ |
| " - The `before` key is used to define architectural information that should be rendered before the values are represented.", |
| " - The `after` key is used to define architectural information that should be rendered description after the values are represented." |
| ], |
| [ |
| "If the property value is of type `string`, this behaves as having a description with just the _before_ key, ", |
| "`before` and `after` have no architectural significance, this is just for rendering." |
| ] |
| ] |
| }, |
| "display": { |
| "info": [ |
| "The display name of the field.", |
| "When null the `name` property is used as the display name.", |
| "Some architectural fields use this property, it is preferred to use the `name` property instead." |
| ], |
| "deprecated": true, |
| "type": [ |
| "string", |
| "null" |
| ] |
| }, |
| "volatile": { |
| "info": [ |
| "The volatile property indicates whether a field's value may change between different accesses, even if it does not appear to be modified. In general, it means that the field's value might be updated by the hardware.", |
| "For Example:", |
| [ |
| "- A status register field changing value.", |
| "- A counter incrementing." |
| ] |
| ], |
| "default": false, |
| "type": "boolean" |
| }, |
| "name": { |
| "info": [ |
| "The canonical name of the field. The name must be unique within this fieldset." |
| ], |
| "type": [ |
| "string", |
| "null" |
| ] |
| }, |
| "rangeset": { |
| "$ref": "../Rangeset.json", |
| "info": [ |
| "A rangeset indicates the location this field appears in it's parent.", |
| [ |
| " - `0`: This field appears at the 0th location.", |
| " - `3:0`: This field is a 4 bit field spanning from the 3rd most significant bit (msb) to the 0th least significant bit (lsb) of it's parent.", |
| " - `5, 3:2, 0`: This field's msb is at 5th bit and lsb is at the 0th bit, with 4th bit and 1st bit not being a part of this field." |
| ], |
| "The width of the rangeset represents the width of this field." |
| ] |
| }, |
| "resets": { |
| "$ref": "../FieldResets.json", |
| "info": [ |
| "The reset value that applies to this field" |
| ] |
| }, |
| "values": { |
| "$ref": "../Valuesets/ValuesetAbstract.json#/definitions/children", |
| "info": [ |
| "A set of __Value__ objects. Each object indicates one of the valid values that may be present in this field, along with a textual description of its meaning." |
| ] |
| } |
| }, |
| "required": [ |
| "name", |
| "rangeset" |
| ], |
| "title": "Field", |
| "type": "object", |
| "examples": [ |
| { |
| "_type": "Fields.Field", |
| "name": "F1", |
| "rangeset": [ |
| { |
| "_type": "Range", |
| "start": 2, |
| "width": 4 |
| } |
| ], |
| "description": { |
| "_type": "Description", |
| "before": "A field in a register called F1", |
| "after": "All other values are reserved" |
| }, |
| "values": { |
| "_type": "Valuesets.Values", |
| "values": [ |
| { |
| "_type": "Values.Value", |
| "meaning": "First value", |
| "value": "'00'" |
| }, |
| { |
| "_type": "Values.Value", |
| "meaning": "Second value", |
| "value": "'10'" |
| }, |
| { |
| "_type": "Values.Value", |
| "meaning": "Third value", |
| "value": "'01'" |
| } |
| ] |
| }, |
| "resets": { |
| "_type": "FieldResets", |
| "domains": { |
| "cold": { |
| "_type": "Values.Value", |
| "value": "'00'", |
| "meaning": "The reset value, which resets to First value" |
| } |
| } |
| }, |
| "volatile": false |
| } |
| ], |
| "$schema": "http://json-schema.org/draft-04/schema#", |
| "additionalProperties": false |
| }</code></pre> |
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