CMSIS-SVD  Version 1.3.9
CMSIS System View Description
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/device/peripherals element

All peripherals of a device are enclosed within the tag <peripherals>.




Parent Element Element Chain
device /device element
Child Elements Description Type Occurrence
peripheral Define the sequence of peripherals. peripheralType 1..*


/device/peripherals/peripheral element

At least one peripheral has to be defined.

  • Each peripheral describes all registers belonging to that peripheral.
  • The address range allocated by a peripheral is defined through one or more address blocks.
  • An address block and register addresses are specified relative to the base address of a peripheral. The address block information can be used for constructing a memory map for the device peripherals.

Starting version 1.3 of the SVD specification, arrays of peripherals can be specified. The single peripheral description gets duplicated automatically into an array. The number of array elements is specified by the <dim> element. To define arrays, the <name> needs the format myPeripheral[%s]. The tag <dimIncrement> specifies the address offset between two peripherals. To create copies of a peripheral using different names, you must use the derivedFrom attribute.

The memory map does not contain any information about physical memory. The memory of a device is described as part of the CMSIS-Pack device description.


<description>Timer 1 is a standard timer ... </description>
<description>Alternate Timer 1 is a special timer execution mode ... </description>

Two timer peripheral descriptions are specified for the same memory block. No redefined addresses will be reported for both peripherals.


Parent Element Element Chain
peripherals /device/peripherals element
Attributes Description Type Occurrence
derivedFrom Specify the peripheral name from which to inherit data. Elements specified subsequently override inherited values. dimableIdentifierType 0..1
Child Elements Description Type Occurrence
  Refer to dimElementGroup for details about the colored elements.
dim Define the number of elements in an array. scaledNonNegativeInteger 0..1
dimIncrement Specify the address increment, in Bytes, between two neighboring array members in the address map. scaledNonNegativeInteger 0..1
dimIndex Do not define on peripheral level. By default, <dimIndex> is an integer value starting at 0. dimIndexType 0..1
dimName Specify the name of the C-type structure. If not defined, then the entry of the <name> element is used. idnetifierType 0..1
dimArrayIndex Grouping element to create enumerations in the header file. dimArrayIndexType 0..1
name The string identifies the peripheral. Peripheral names are required to be unique for a device. The name needs to be an ANSI C identifier to generate the header file. You can use the placeholder [%s] to create arrays. dimableIdentifierType 1..1
version The string specifies the version of this peripheral description. xs:string 0..1
description The string provides an overview of the purpose and functionality of the peripheral. xs:string 0..1
alternatePeripheral All address blocks in the memory space of a device are assigned to a unique peripheral by default. If multiple peripherals describe the same address blocks, then this needs to be specified explicitly. A peripheral redefining an address block needs to specify the name of the peripheral that is listed first in the description. dimaleIdentifierType 0..1
groupName Define a name under which the System Viewer is showing this peripheral. xs:Name 0..1
prependToName Define a string as prefix. All register names of this peripheral get this prefix. identifierType 0..1
appendToName Define a string as suffix. All register names of this peripheral get this suffix. identifierType 0..1
headerStructName Specify the base name of C structures. The headerfile generator uses the name of a peripheral as the base name for the C structure type. If <headerStructName> element is specfied, then this string is used instead of the peripheral name; useful when multiple peripherals get derived and a generic type name should be used. dimableIdentifierType 0..1
disableCondition Define a C-language compliant logical expression returning a TRUE or FALSE result. If TRUE, refreshing the display for this peripheral is disabled and related accesses by the debugger are suppressed.

Only constants and references to other registers contained in the description are allowed: <peripheral>-><register>-><field>, for example, (System->ClockControl->apbEnable == 0). The following operators are allowed in the expression [&&,||, ==, !=, >>, <<, &, |].
Use this feature only in cases where accesses from the debugger to registers of un-clocked peripherals result in severe debugging failures. SVD is intended to provide static information and does not include any run-time computation or functions. Such capabilities can be added by the tools, and is beyond the scope of this description language.
stringType 0..1
baseAddress Lowest address reserved or used by the peripheral. scaledNonNegativeInteger 1..1
  Refer to registerPropertiesGroup for details about the colored elements.
size Define the default bit-width of any register contained in the device (implicit inheritance). scaledNonNegativeInteger 0..1
access Define default access rights for all registers. accessType 0..1
protection Define default protection rights for all registers. protectionStringType 0..1
resetValue Define the default value for all registers at RESET. scaledNonNegativeInteger 0..1
resetMask Identify which register bits have a defined reset value. scaledNonNegativeInteger 0..1
addressBlock Specify an address range uniquely mapped to this peripheral. A peripheral must have at least one address block, but can allocate multiple distinct address ranges. If a peripheral is derived from another peripheral, the addressBlock is not mandatory. addressBlockType 0/1..*
interrupt A peripheral can have multiple associated interrupts. This entry allows the debugger to show interrupt names instead of interrupt numbers. interruptType 0..*
registers Group to enclose register definitions. registersType 0..1


/device/peripherals/peripheral/addressBlock element

Specify an address range uniquely mapped to this peripheral. A peripheral must have at least one address block. If a peripheral is derived form another peripheral, the <addressBlock> is not mandatory.


Parent Element Element Chain
peripheral /device/peripherals/peripheral element
Child Elements Description Type Occurrence
offset Specifies the start address of an address block relative to the peripheral baseAddress. scaledNonNegativeInteger 1..1
size Specifies the number of addressUnitBits being covered by this address block. The end address of an address block results from the sum of baseAddress, offset, and (size - 1). scaledNonNegativeInteger 1..1
usage The following predefined values can be used:
  • registers
  • buffer
  • reserved.
enumerated token 1..1
protection Set the protection level for an address block. protectionStringType 0..1


/device/peripherals/peripheral/interrupt element

A peripheral can have multiple interrupts. This entry allows the debugger to show interrupt names instead of interrupt numbers.


Parent Element Element Chain
peripheral /device/peripherals/peripheral element
Child Elements Description Type Occurrence
name The string represents the interrupt name. stringType 1..1
description The string describes the interrupt. xs:string 0..1
value Represents the enumeration index value associated to the interrupt. xs:integer 1..1