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Element: SharedIODescription

Document type

SharedIODescription

Document XPath

/SharedIODescription

Schema XPath

/ConfigRecord/Module/SharedDataRegions/SharedData/SharedIODescription

Description

The SharedIODescription element is the root element of a SharedIODescription document that defines the configuration of a shared I/O region.

A shared I/O region is a memory area on the target that the platform provider can make available for access by applications in the CoreOSDescription document (see /CoreOSDescription/HardwareConfiguration/sharedIO). For example, the wrSbc750gx board has four user LEDs. If the platform provider has configured the platform to make the memory locations of the LEDs available as a shared I/O pool, the system integrator can configure a shared I/O region for access to those LEDs.

You create a SharedIODescription document as a file with SharedIODescription as its root element. You include the shared data configuration file into your system configuration using an xi:include element in the SharedData element. Optionally, you can include the shared data description inline in the SharedData element.

When creating a shared I/O description as a separate file, you should begin with an XML declaration:

<?xml version="1.0" encoding="UTF-8"?>
			

Following the XML declaration, insert the SharedIODescription element:

<SharedIODescription
 xmlns="http://www.windriver.com/vxWorks653/ConfigRecord"
 xmlns:xi="http://www.w3.org/2001/XInclude"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://www.windriver.com/vxWorks653/ConfigRecord ../cleanschema/Application.xsd">
 VirtualAddress="0x50001000"
 SystemAccess="READ_ONLY"
 CachePolicy="DEFAULT"
</SharedIODescription>
 

The SharedIODescription element must include the required XML attributes that identify the schema and namespace for the document. The first three attributes are standard and should be entered exactly as shown. The xsi:schemaLocation attribute associates the namespace (http://www.windriver.com/vxWorks653/ConfigRecord) with the schema file (Application.xsd). You should provide the correct path to your copy of the schema. The location of the schema files in the install is installDir/vxworks653-2.2/target/config/xml/cleanschema.

If you use a schema-aware XML editor to create your files, it will probably create these attributes for you.

The other attributes shown are part of the SharedIODescription element. They are described below.

Use

Required

Children

None

Attributes

CachePolicy

SystemAccess

VirtualAddress

Restrictions

None

Attribute: CachePolicy

Document XPath
/SharedIODescription/@CachePolicy
Schema XPath
/ConfigRecord/Module/SharedDataRegions/SharedData/SharedIODescription/@CachePolicy
Description

The caching policy for the shared I/O region.

Use

Optional

Target location

ConfigRecord

XML data type

CachePolicyType

Destination data type

Unsigned 32 bit integer

Behavior if not specified

A value of DEFAULT is used.

Values with special meanings

None

Restrictions

None

Attribute: SystemAccess

Document XPath
/SharedIODescription/@SystemAccess
Schema XPath
/ConfigRecord/Module/SharedDataRegions/SharedData/SharedIODescription/@SystemAccess
Description

The core OS access rights for the shared I/O region. Note that the values of this attribute may be interpreted differently, or may not all be supported, on different target architectures.

Use

Optional

Target location

ConfigRecord

XML data type

UserAccessRightsType

Destination data type

Signed 32 bit integer

Behavior if not specified

The core OS has read and write access to the region.

Values with special meanings

NONE: The core OS has no access to the region.

READ_ONLY: The core OS has read-only access to the region.

READ_WRITE: The core OS has read and write access to the region.

WRITE_ONLY: The core OS has write-only access to the region.

Restrictions

Attribute: VirtualAddress

Document XPath
/SharedIODescription/@VirtualAddress
Schema XPath
/ConfigRecord/Module/SharedDataRegions/SharedData/SharedIODescription/@VirtualAddress
Description

The virtual address of the shared I/O region.

Use

Optional

Target location

ConfigRecord

XML data type

DecOrHexValueType

Destination data type

Unsigned 32 bit integer

Behavior if not specified

The address is assigned at runtime.

Values with special meanings

0: The address is assigned at runtime.

Restrictions



Generated on 2007-10-15 17:17:22.