RealView® Development Suite Glossary

The items in this glossary are listed in alphabetical order, with any symbols and numerics appearing at the end.

AAPCS

See Procedure Call Standard for the ARM® Architecture.

ABI for the ARM Architecture (base standard) (BSABI)

The ABI for the ARM Architecture is a collection of specifications, some open and some specific to ARM architecture, that regulate the inter-operation of binary code in a range of ARM architecture-based execution environments. The base standard specifies those aspects of code generation that must be standardized to support inter-operation and is aimed at authors and vendors of C and C++ compilers, linkers, and runtime libraries.

Adaptive clocking

A technique used by RealView ICE where it sends out a clock signal and then waits for the returned clock before generating the next clock pulse. The technique enables the RealView ICE run control unit to adapt to differing signal drive capabilities and differing cable lengths.

Advanced eXtensible Interface (AXI)

A bus protocol that supports separate address/control and data phases, unaligned data transfers using byte strobes, burst-based transactions with only start address issued, separate read and write data channels to enable low-cost DMA, ability to issue multiple outstanding addresses, out-of-order transaction completion, and easy addition of register stages to provide timing closure.

The AXI protocol also includes optional extensions to cover signaling for low-power operation.

AXI is targeted at high performance, high clock frequency system designs and includes a number of features that make it very suitable for high speed sub-micron interconnect.

Advanced Microcontroller Bus Architecture (AMBA®)

On-chip communications standard for high-performance 32-bit and 16-bit embedded microcontrollers.

Advanced High-performance Bus (AHB)

A bus protocol with a fixed pipeline between address/control and data phases. It only supports a subset of the functionality provided by the AMBA AXI protocol. The full AMBA AHB protocol specification includes a number of features that are not commonly required for master and slave IP developments and ARM Limited recommends only a subset of the protocol is usually used. This subset is defined as the AMBA AHB-Lite protocol.

See Also Advanced Microcontroller Bus Architecture and AHB-Lite.

AHB

See Advanced High-performance Bus.

AHB Access Port (AHB-AP)

CoreSight™ supports access to a system bus infrastructure using the AHB Access Port (AHB-AP) in the Debug Access Port (DAP). The AHB-AP provides an AHB master port for direct access to system memory. If an alternate bus protocol is implemented, you can use an AHB bridge to map transactions. For example, you can use an AHB to AXI bridge to enable access to an AXI bus matrix.

CoreSight also supports AHB bus tracing using an AHB Trace Macrocell (HTM).

See Also Advanced eXtensible Interface, AHB Trace Macrocell, CoreSight, and Debug Access Port.

AHB-AP

See AHB Access Port.

AHB-Lite

A subset of the full AMBA AHB protocol specification. It provides all of the basic functions required by the majority of AMBA AHB slave and master designs, particularly when used with a multi-layer AMBA interconnect. In most cases, the extra facilities provided by a full AMBA AHB interface are implemented more efficiently by using an AMBA AXI protocol interface.

AHB Trace Macrocell (HTM)

The AHB Trace Macrocell is a trace source that makes bus information visible that cannot be inferred from the processor trace using an ETM:

  • An understanding of multi-layer bus utilization.

  • Software debug. For example, visibility of access to memory areas and data accesses.

  • Bus event detection for trace trigger or filters, and for bus profiling.

See Also Advanced High-performance Bus.

AMBA

See Advanced Microcontroller Bus Architecture.

AMBA Trace Bus (ATB)

The AMBA Trace Bus transfers trace data through CoreSight infrastructure in a SoC. Trace sources are ATB masters, and sinks are ATB slaves. Link components provide both master and slave interfaces.

See Also CoreSight.

APB-AP

See Debug Access Port.

armar

The ARM librarian.

armasm

The ARM assembler.

armcc

The ARM compiler for C and C++ code.

ARM Advanced SIMD Extension

ARM Advanced SIMD Extension is an optional component of ARMv7 architecture. It is a 64/128 bit hybrid SIMD technology targeted at advanced media and signal processing applications and embedded processors. It is implemented as part of the ARM core, but has its own execution pipelines and a register bank that is distinct from the ARM core register bank.

ARM Advanced SIMD Extension supports integer, fixed-point, and single-precision floating-point SIMD operations. These instructions are available in both ARM and Thumb-2.

ARM Advanced SIMD Extension is also known as ARM NEON Technology (NEON™).

ARM instruction

A word that encodes an operation for an ARM processor operating in ARM state. ARM instructions must be word-aligned.

See Also Thumb instruction, Thumb-2 instruction, and Thumb-2EE instruction.

armlink

The ARM linker.

ARM state

A processor that is executing ARM instructions is operating in ARM state. The processor switches to Thumb state (and to recognizing Thumb instructions) when directed to do so by a state-changing instruction such as BX, BLX.

See Also Jazelle® state, Thumb state, and ThumbEE state.

ATB

See AMBA Trace Bus.

AXI

See Advanced eXtensible Interface.

BCD file

See Board/Chip Definition (BCD) file.

Big-endian

In the context of the ARM architecture, big-endian is defined as the memory organization in which the least significant byte of a word is at a higher address than the most significant byte.

See Also Little-endian.

Board file

RealView Debugger uses this term to refer to the top-level configuration file, normally called rvdebug.brd, that references one or more other configuration files. A board file contains:

  • the Debug Configuration (connection-level) settings

  • references to the Debug Interface configuration file that identifies the targets on the development platform

  • references to any Board/Chip Definition (BCD) files assigned to a connection.

See Also Board/Chip Definition (BCD) file, Debug Configuration, Debug Interface, Development platform, and Target.

Board/Chip Definition (BCD) file

In the context of RealView Debugger, a BCD file enables you to define the memory map and memory mapped registers for a target development board or processor. Various BCD files are provided with RVDS for ARM development boards (for example AP.bcd) and processor core modules (for example CM940T.bcd).

See Also Board file and Debug Configuration.

Breakpoint unit

In the context of RealView Debugger, a unit within a Chained breakpoint that combines with other breakpoint units to create a complex hardware breakpoint.

See Also Chained breakpoint and Hardware breakpoint.

BSABI

See ABI for the ARM Architecture (base standard).

Canonical Frame Address (CFA)

In DWARF, this is an address on the stack specifying where the call frame of an interrupted function is located.

Captive thread

Captive threads are all threads that can be brought under the control of RealView Development Suite. Special threads, called non-captive threads, are essential to the operation of Running System Debug (RSD) and so are not under debugger control. Non-captive threads are grayed out in the GUI.

See Also Running System Debug.

CFA

See Canonical Frame Address.

Chained breakpoint

In the context of RealView Debugger, a complex breakpoint that comprises multiple hardware breakpoint units.

See Also Breakpoint unit, Conditional breakpoint, Data breakpoint, and Hardware breakpoint.

Chained tracepoint

In the context of RealView Debugger, a complex tracepoint that comprises multiple tracepoint units.

See Also Tracepoint and Tracepoint unit.

Conditional breakpoint

A breakpoint that has one or more condition qualifiers assigned. The breakpoint is activated when all assigned conditions are met, and either stops or continues execution depending on the action qualifiers that are assigned. The condition normally references the values of program variables that are in scope at the breakpoint location.

See Also Chained breakpoint, Data breakpoint, Hardware breakpoint, Instruction breakpoint, Software breakpoint, and Unconditional breakpoint.

Core module

In the context of the ARM Integrator™, an add-on development board that contains an ARM architecture-based processor and local memory. Core modules can run stand-alone, or can be stacked onto Integrator motherboards.

See Also Integrator.

CoreSight

CoreSight is an infrastructure that enables the debugging, monitoring, and optimization of performance of a complete System on Chip (SoC) design.

See Also CoreSight ECT, CoreSight ETB, CoreSight ETM, Trace Funnel, and Trace Port Interface Unit.

CoreSight ECT

CoreSight ECT is a control and access component that supports the interaction and synchronization of multiple triggering events within a SoC:

See Also CoreSight, Cross Trigger Interface, Cross Trigger Matrix, and Embedded Cross Trigger.

CoreSight ETB

CoreSight ETB is a trace sink that provides on-chip storage of trace data using a configurable sized RAM.

See Also CoreSight, CoreSight ETB, Embedded Trace Buffer, and Embedded Trace Macrocell.

CoreSight ETM

CoreSight ETM is a trace source that provides processor driven trace through an ATB compliant trace port.

See Also AMBA Trace Bus, CoreSight and Embedded Trace Macrocell.

CPSR

See Current Program Status Register.

Cross Trigger Interface (CTI)

The Cross Trigger Interface provides the interface between a component or subsystem and the Cross Trigger Matrix. The system requires a CTI for each subsystem that supports cross triggering.

See Also CoreSight, CoreSight ECT, Cross Trigger Matrix, and Embedded Cross Trigger.

Cross Trigger Matrix (CTM)

The Cross Trigger Matrix combines the trigger requests generated from CTIs and broadcasts them to all CTIs as channel triggers. This enables subsystems to interact, cross trigger, with one another. CTMs can be connected together to increase the number of CTIs

See Also CoreSight, CoreSight ECT, Cross Trigger Interface, and Embedded Cross Trigger.

CTI

See Cross Trigger Interface.

CTM

See Cross Trigger Matrix.

Current Program Status Register (CPSR)

A register containing the current state of control bits and flags.

See Also Program Status Register and Saved Program Status Register.

DAP

See Debug Access Port.

Data breakpoint

A hardware breakpoint that activates when a given location is accessed in a specific way. The breakpoint can also check for a specific data value being access at the given location, if required.

See Also Chained breakpoint, Conditional breakpoint, Hardware breakpoint, Instruction breakpoint, Software breakpoint, and Unconditional breakpoint.

DCC

See Debug Communications Channel.

Debug Agent (DA)

The Debug Agent resides on the target to provide target-side support for Running System Debug (RSD) in RealView Debugger. The Debug Agent can be a thread or built into the RTOS. The Debug Agent and RealView Development Suite communicate with each other using the Debug Communications Channel (DCC). This enables data to be passed between the debugger and the target using the ICE interface, without stopping the program or entering debug state.

See Also Running System Debug and Debug Communications Channel.

Debug Access Port (DAP)

The Debug Access Port is a control and access component that enables debug access to the complete SoC through system master ports.

External read/write access to the internal interface is provided by the JTAG Debug Port (JTAG-DP). The JTAG-DP is a standard JTAG interface for debug access and provides standard JTAG access to an SoC through the DAP. It interfaces to the DAP internal bus.

Internal access to on-chip busses and other interfaces is provided by the Access Ports (APs). The three APs are:

  • the AHB Access Port (AHB-AP) that provides an AHB-Lite master for access to a system AHB bus

  • the APB Access Port (APB-AP) that provides an AMBA 3 APB master for access to the Debug APB that configures all CoreSight components

  • the JTAG Access Port (JTAG-AP) that provides JTAG access to on-chip components and operates as a JTAG master port to drive JTAG chains throughout the SoC.

See Also CoreSight.

Debug Communications Channel (DCC)

A debug communications channel enables data to be passed between RealView Development Suite and the EmbeddedICE logic on the target using the JTAG interface, without stopping the program flow or entering debug state.

Debug Configuration

In the context of RealView Debugger, a Debug Configuration defines a debugging environment for your development platform.

See Also Board file, Board/Chip Definition (BCD) file, Debug Interface and Target.

Debug Interface

In the context of RealView Debugger, the Debug Interface identifies the targets on your development platform, and provides the mechanism that enables RealView Debugger to communicate with those targets. The Debug Interface corresponds directly to a piece of hardware or a software simulator.

See Also Debug Configuration and Target.

Deprecated

A deprecated option or feature is one that you are strongly discouraged from using. Deprecated options and features are to be removed in future versions of the product.

Development platform

The Development Platform contains the components, either hardware or simulated, that you are using to develop your application. It can include:

  • a base board, such as an Integrator/CP

  • peripherals

  • one or more ARM architecture-based processors

  • CoreSight components

  • one or more DSPs.

See Also CoreSight and Target.

Doubleword

In the context of the ARM architecture, a 64-bit unit of information. Contents are taken as being an unsigned integer unless otherwise stated.

DWARF

Debug With Arbitrary Record Format.

ECT

See Embedded Cross Trigger.

ELF

Executable and Linking Format.

Embedded assembler

Embedded assembler is assembler code that is included in a function, and is separate from other C or C++ functions.

Embedded Cross Trigger (ECT)

The Embedded Cross Trigger provides a standard interconnect mechanism to pass debug or profiling events around the SoC. It comprises:

  • Cross Trigger Interface (CTI)

  • Cross Trigger Matrix (CTM).

See Also CoreSight ECT.

Embedded Trace Buffer™ (ETB™)

The Embedded Trace Buffer provides logic inside the core that extends the information capture functionality of the Embedded Trace Macrocell.

See Also CoreSight ETB and Embedded Trace Macrocell.

Embedded Trace Macrocell™ (ETM)

A block of logic, embedded in the hardware, that is connected to the address, data, and status signals of the processor. It broadcasts branch addresses, and data and status information in a compressed protocol through the trace port. It contains the resources used to trigger and filter the trace output.

See Also CoreSight ETM.

EmbeddedICE® logic

The EmbeddedICE logic is an on-chip logic block that provides TAP-based debug support for ARM architecture-based processors. It is accessed through the TAP controller on the ARM architecture-based processor using the JTAG interface.

See Also IEEE1149.1.

Emulator

In the context of target connection hardware, an emulator provides an interface to the pins of a real core (emulating the pins to the external world) and enables you to control or manipulate signals on those pins.

ETB

See Embedded Trace Buffer.

ETM

See Embedded Trace Macrocell.

ETV

See Extended Target Visibility.

Execution vehicle

Part of the debug target interface, execution vehicles process requests from the client tools to the target.

See Also Debug Interface.

Execution view

The address of regions and sections after the image has been loaded into memory and started execution.

Extended Target Visibility (ETV)

Extended Target Visibility enables RealView Development Suite to access features of the underlying target, such as chip-level details provided by the hardware manufacturer or SoC designer.

Filtering

In the context of RealView Debugger Trace, a facility that enables you to refine the results of a trace capture that has already been performed in RealView Debugger. This is useful if you want to refine your area of interest within the display.

FIQ

Fast Interrupt.

fromelf

The ARM image conversion utility. This accepts ELF format input files and converts them to a variety of output formats. fromelf can also generate text information about the input image, such as code and data size.

GCC

GNU Compiler Collection.

GDB

GNU Debugger.

GPIO

General Purpose Input/Output.

Halfword

In the context of the ARM architecture, defined as a 16-bit unit of information. Contents are taken as being an unsigned integer unless otherwise stated.

Halted System Debug (HSD)

Usually used for OS aware debugging, Halted System Debug (HSD) means that a target can only be debugged when it is not running. Any target must be stopped before carrying out any analysis of the system. With the target stopped, RealView Debugger presents OS awareness information by reading and interpreting target memory.

See Also Running System Debug.

Hardware breakpoint

A breakpoint that is implemented using non-intrusive additional hardware. Hardware breakpoints are the only method of halting execution when the location is in Read Only Memory (ROM) or Flash. Using a hardware breakpoint often results in the processor halting completely. This is usually undesirable for a real-time system.

See Also Chained breakpoint, Conditional breakpoint, Data breakpoint, Instruction breakpoint, Software breakpoint, and Unconditional breakpoint.

Hint instruction

A hint instruction provides information to the hardware that the hardware can take advantage of. An implementation can choose whether to implement hint instructions or not. If they are not implemented, they execute as NOP.

HSD

See Halted System Debug.

HTM

See AHB Trace Macrocell.

ICE Extension Unit

A hardware extension to the EmbeddedICE logic that provides more breakpoint units.

IEEE 1149.1

The IEEE Standard that defines TAP. Commonly (but incorrectly) referred to as JTAG.

Image

An executable file that can be loaded onto a processor for execution.

A binary execution file that can be loaded onto a processor and given a thread of execution. An image can have multiple threads. An image is related to the processor that is running the default thread for the image.

Immediate values

Values that are encoded directly in the instruction and used as numeric data when the instruction is executed. Many ARM and Thumb instructions enable small numeric values to be encoded as immediate values within the instruction that operates on them.

Implementation defined

In the context of the ARM architecture, this means that the behavior is not architecturally defined, but must be defined and documented by individual implementations.

In-Circuit Emulator

A device enabling access to and modification of the signals of a circuit while that circuit is operating.

Input section

Contains code or initialized data or describes a fragment of memory that must be set to zero before the application starts.

Instruction breakpoint

A location in the image containing an instruction that, if executed, activates a breakpoint. The breakpoint activation can be delayed by assigning condition qualifiers, and subsequent execution of the image is determined by any actions assigned to the breakpoint.

See Also Conditional breakpoint, Data breakpoint, Hardware breakpoint, Software breakpoint, and Unconditional breakpoint.

Instruction Register (IR)

When referring to a TAP controller, a register that controls the operation of the TAP.

Instruction Set System Model (ISSM)

In the context of RealView Development Suite, a set of models that simulate the ARM Cortex™ family of processors. These models are provided with RealView Development Suite.

Integrator

A range of ARM hardware development platforms. Core modules are available that contain the processor and local memory.

Interworking

A method of working that enables branches between ARM and Thumb code.

IRQ

Interrupt Request.

ISSM

See Instruction Set System Model.

IT block

A block of up to four instructions following the 16-bit Thumb-2 If-Then (IT) instruction. Each instruction in the block is conditional. The conditions for the instructions are either all the same, or some can be the inverse of others.

Jazelle

The Jazelle architecture extends the existing ARM architecture to enable direct execution of selected Java Virtual Machine (JVM) opcodes.

Jazelle state

A processor that is executing Jazelle bytecode instructions is operating in Jazelle state.

See Also ARM state, Thumb state, and ThumbEE state.

JTAG

Joint Test Action Group.

JTAG-AP

See Debug Access Port.

JTAG-DP

See Debug Access Port.

JTAG interface unit

In the context of ARM tools, a protocol converter that converts low-level commands from RealView Development Suite into JTAG signals to the processor, for example to the EmbeddedICE logic and the ETM.

Little-endian

In the context of the ARM architecture, little-endian is defined as the memory organization in which the most significant byte of a word is at a higher address than the least significant byte.

See Also Big-endian.

Load view

The address of regions and sections when the image has been loaded into memory but has not yet started execution.

LVDS

Low Voltage Digital Signaling.

Memory hint

In the context of the ARM architecture, a memory hint instruction enables a programmer to provide advance information to memory systems about future memory accesses, without actually loading or storing any data.

Monitor mode

In the context of TrustZone®, an ARM mode that is responsible for switching the core between the Secure and Normal state. Do not confuse Monitor mode with Monitor debug-mode.

See Also Normal state, Normal world, Secure state, Secure world, and TrustZone.

MPCore

An integrated Symmetric Multiprocessor system (SMP) delivered as a traditional uniprocessor core. The chip contains up to four ARM1136J-S™ based CPUs with cache coherency.

MPU

Multi-Processor Unit.

NEON

See ARM Advanced SIMD Extension.

Normal state

In the context of TrustZone, the processor is in Normal state if the Secure Configuration Register (SCR) NS-bit is 1, and the processor is in any mode other than Monitor mode. The core cannot access the Secure world.

See Also Monitor mode, Normal world, Secure state, Secure world, and TrustZone.

Normal world

In the context of TrustZone, all the hardware, both core and system, that is accessible when the core is in Normal state.

See Also Monitor mode, Normal state, Secure state, Secure world, and TrustZone.

Output section

A contiguous sequence of input sections that have the same RO, RW, or ZI attributes. The sections are grouped together in larger fragments called regions. The regions are grouped together into the final executable image.

See Also Region.

OS-awareness

OS-awareness is a feature provided by RealView Debugger that enables you to:

  • debug applications running on an embedded OS development platform, such as a Real Time Operating System (RTOS)

  • present thread information and scope some debugging operations to specific threads.

PC

Program Counter.

PCH

See PreCompiled Header.

PreCompiled Header (PCH)

A header file that is precompiled. This avoids the compiler having to compile the file each time it is included by source files.

Procedure Call Standard for the ARM Architecture (AAPCS)

Procedure Call Standard for the ARM Architecture defines how registers and the stack will be used for subroutine calls.

Profiling

In the context of RealView Debugger Trace, the accumulation of statistics during execution of a program being debugged, to measure performance or to determine critical areas of code.

Program Counter (PC)

In the context of the ARM architecture, integer register R15.

Program image

See Image.

Program Status Register (PSR)

Contains some information about the current program and some information about the current processor. Also referred to as Current PSR (CPSR), to emphasize the distinction between it and the Saved PSR (SPSR). The SPSR holds the value the PSR had when the current function was called, and which will be restored when control is returned.

An Enhanced Program Status Register (EPSR) contains an additional bit (the Q bit, signifying saturation) used by some ARM architecture-based processors, including the ARM9E.

See Also Current Program Status Register and Saved Program Status Register.

Project template

A collection of RealView Debugger and RVCT configuration files for specific target development platforms. These templates enable you to create a target-specific development project in the Eclipse IDE.

See Also RealView Compilation Tools (RVCT) and RealView Debugger.

PSR

See Program Status Register.

PU

Protection Unit.

Read-Only Position Independent (ROPI)

In the context of the ARM architecture, code or read-only data that can be placed at any address.

Read Write Position Independent (RWPI)

In the context of the ARM architecture, read/write data addresses that can be changed at runtime.

RealMonitor

A small program that, when integrated into your target application or Real-Time Operating System (RTOS), enables you to observe and debug your target while parts of your application continue to run.

Real Time System Model (RTSM)

A Real Time System Model contains a hard-coded system containing one or more specific simulated processors.

RealView ARMulator ISS (RVISS)

One of the ARM simulators supplied with RealView Development Suite.

RVISS is a collection of programs that simulate the instruction sets and architecture of various ARM processors. This provides instruction-accurate simulation and enables ARM and Thumb executable programs to be run on non-native hardware.

RVISS provides modules that model:

  • the ARM processor core

  • the memory used by the processor.

There are alternative predefined models for each of these parts. However, you can create your own models if a supplied model does not meet your requirements.

RealView Compilation Tools (RVCT)

RealView Compilation Tools is a suite of tools, together with supporting documentation and examples, that enables you to write and build applications for the ARM family of RISC processors.

RealView Debugger

The latest debugger software from ARM Limited that enables you to make use of a debug agent in order to examine and control the execution of software running on a debug target. RealView Debugger is supplied in both Windows and Red Hat Linux versions.

RealView Debugger Trace

Part of the RealView Development Suite product that extends the debugging capability with the addition of real-time program and data tracing. It is available from the RealView Debugger Code window.

RealView Development Suite (RVDS)

The latest suite of software development applications, together with supporting documentation and examples, that enable you to write and debug applications for the ARM family of RISC processors.

See Also ARM Developer Suite.

RealView ICE (RVI)

A JTAG-based debug solution to debug software running on ARM architecture-based processors. RealView ICE must be purchased as a separate product.

RealView Trace (RVT)

Works in conjunction with ARM RealView ICE to provide real-time trace functionality for software running in leading edge System-on-Chip devices with deeply embedded processor cores. The RealView Trace hardware must be purchased as a separate product.

Region

In an image, a region is a contiguous sequence of one to three output sections (RO, RW, and ZI). A region typically maps onto a physical memory device, such as ROM, RAM, or peripheral.

See Also Root region.

ROPI

See Read-Only Position Independent.

Root region

In an image, regions having the same load and execution address. A non-root region is a region that must be copied from its load address to its execution address.

RSD

See Running System Debug.

RTSM

See Real Time System Model.

Running System Debug (RSD)

Used for OS-aware debugging, Running System Debug (RSD) means that a target can be debugged when it is running. This means that the debug target does not have to be stopped before carrying out any analysis of the system. RSD gives access to the application using a Debug Agent (DA) that resides on the target. The Debug Agent is scheduled along with other tasks in the system.

See Also Debug Agent and Halted System Debug.

RVCT

See RealView Compilation Tools.

RVDS

See RealView Development Suite.

RVISS

See RealView ARMulator ISS.

RVT

See RealView Trace.

RWPI

See Read Write Position Independent.

Saved Program Status Register (SPSR)

A register that holds a copy of what was in the Current Program Status Register before the most recent exception. Each exception mode has its own SPSR.

Scatter-loading

Assigning the address and grouping of code and data sections individually rather than using single large blocks.

Section

In the context of applications targeted at ARM architecture-based processors, a block of software code or data for an Image.

See Also Input section and Output section.

Secure state

In the context of TrustZone, the processor is in Secure state if the Secure Configuration Register (SCR) NS-bit is 0, or the processor is in Monitor mode. The core can access both the Secure and Normal worlds.

See Also Monitor mode, Normal state, Normal world, Secure world, and TrustZone.

Secure World

In the context of TrustZone, all the hardware, both core and system, that is only accessible when the core is in Secure state.

See Also Monitor mode, Normal state, Normal world, Secure state, and TrustZone.

Semihosting

A mechanism whereby the target communicates I/O requests made in the application code to the host system, rather than attempting to support the I/O itself.

Simple tracepoint

A type of tracepoint that enables you to set trigger points, trace start and end points, or trace ranges for memory and data accesses.

See Also Tracepoints.

Simulator

In the context of the ARM tools, a simulator executes non-native instructions in software (simulating a core).

See Also Instruction Set System Model, RealView ARMulator ISS, and SoC Designer Simulator.

SoC Designer Simulator

SoC Designer Simulator is part of the RealView SoC Designer toolset that can be used for fast modeling, simulation and debugging of complex System-on-Chip (SoC) designs. System and processor models created with the RealView SoC Designer tools can be debugged with SoC Designer Simulator in conjunction with RealView Debugger.

Software breakpoint

A breakpoint that is implemented by replacing an instruction in memory with one that causes the processor to take exceptional action. Because instruction memory must be altered software breakpoints cannot be used where instructions are stored in read-only memory. Using software breakpoints can enable interrupt processing to continue during the breakpoint, making them more suitable for use in real-time systems.

See Also Chained breakpoint, Conditional breakpoint, Data breakpoint, Hardware breakpoint, Instruction breakpoint, Software breakpoint, and Unconditional breakpoint.

SPSR

Saved Program Status Register.

See Also Program Status Register.

Stack Pointer (SP)

Integer register R13.

Supervisor Call (SVC)

An instruction that causes the processor to call a programmer-specified subroutine. Used by the ARM standard C library to handle semihosting. This replaces software interrupt (SWI).

SVC

See Supervisor Call.

SWI

See Supervisor Call.

TAP

See Test Access Port.

TAP Controller

Logic on a device which enables access to some or all of that device for test purposes. The circuit functionality is defined in IEEE1149.1.

See Also Test Access Port and IEEE1149.1.

Target

In the context of RealView Debugger, a Target is the part of your development platform to which RealView Debugger can connect, and on which debugging operations can be performed. A target can be:

  • A runnable target, such as an ARM architecture-based processor or a DSP. When connected to a runnable target, you can perform execution-related debugging operations on that target, such as stepping and tracing.

  • A non-runnable CoreSight component. CoreSight components provide a system wide solution to real-time debug and trace.

See Also CoreSight, Debug Configuration, and Debug Interface.

Target Vehicle

Target vehicles provide RealView Development Suite with a standard interface to disparate targets so that the debugger can connect easily to new target types without having to make changes to the debugger core software.

TCM

Tightly Coupled Memory.

TDI

Test Data Input.

TDO

Test Data Output.

Thumb instruction

One halfword or two halfwords that encode an operation for an ARM architecture-based processor operating in Thumb state. Thumb instructions must be halfword-aligned.

See Also ARM instruction, Thumb-2 instruction, and Thumb-2EE instruction.

Thumb state

A processor that is executing Thumb instructions is operating in Thumb state. The processor switches to ARM state (and to recognizing ARM instructions) when directed to do so by a state-changing instruction such as BX, BLX.

See Also ARM state, Jazelle state, and ThumbEE state.

Thumb-2 instruction

Thumb-2 is a major enhancement of the Thumb instruction set, and is defined by ARMv6T2 and ARMv7M architectures. Thumb-2 provides almost exactly the same functionality as the ARM instruction set. It has both 16-bit and 32-bit instructions, and achieves performance similar to ARM code, but with code density similar to Thumb code.

See Also ARM instruction, Thumb instruction, and Thumb-2EE instruction.

Thumb-2EE instruction

Thumb-2 Execution Environment (Thumb-2EE) is defined by ARMv7 architecture. The Thumb-2EE instruction set is based on Thumb-2, with some changes and additions to make it a better target for dynamically generated code, that is, code compiled on the device either shortly before or during execution.

See Also ARM instruction, Thumb instruction, and Thumb-2 instruction.

ThumbEE state

A processor that is executing Thumb-2EE instructions is operating in ThumbEE state. In this state, the instruction set is almost identical to the Thumb instruction set. However, some instructions have modified behavior, some instructions are not available, and some new instructions become available.

See Also ARM state, Jazelle state, and Thumb state.

TPA

Trace Port Analyzer.

TPIU

See Trace Port Interface Unit.

Trace Funnel

The Trace Funnel combines up to eight trace sources (ETM or HTM) on a single funnel. However, in this release, trace data can be captured only from a single ETM at a time.

See Also AHB Trace Macrocell, CoreSight, CoreSight ETM, and Embedded Trace Macrocell.

Trace Port Interface Unit (TPIU)

The Trace Port Interface Unit is a trace sink that drains trace data off-chip to a TPA, such as RealView Trace.

See Also CoreSight, CoreSight ETB, and CoreSight ETM.

Tracepoint

A tracepoint can be set on a line of source code, a line of assembly code, or a memory address. In RealView Development Suite, you can set a variety of tracepoints to determine exactly what program information is traced.

See Also Chained tracepoint and Tracepoint unit.

Tracepoint unit

In the context of RealView Debugger, a unit within a Chained tracepoint that combines with other tracepoint units to create a complex tracepoint.

See Also Chained tracepoint and Tracepoint.

Trigger

In the context of breakpoints, a trigger is the action of noticing that the breakpoint has been reached by the target and that any associated conditions are met.

In the context of tracing, a trigger is an event that instructs the debugger to stop collecting trace and display the trace information around the trigger position, without halting the processor. The exact information that is displayed depends on the position of the trigger within the buffer.

TrustZone

ARM technology-optimized software that provides a secure execution environment to enable trusted programs and data to be separated from the operating system and applications.

See Also Monitor mode, Normal state, Normal world, Secure state, and Secure world.

Unconditional breakpoint

A breakpoint that does not have a conditional qualifier assigned. The breakpoint activates immediately it is hit, but subsequent image execution is determined by any actions assigned to the breakpoint.

See Also Conditional breakpoint, Data breakpoint, Hardware breakpoint, Instruction breakpoint, Software breakpoint, and Unconditional breakpoint.

Undefined

In the context of the ARM architecture, an attempt to execute an undefined instruction causes an Undefined Instruction exception.

Unpredictable

In the context of the ARM architecture, the result of an unpredictable instruction cannot be relied upon. Unpredictable instructions or results must not represent security holes. Unpredictable instructions must not halt or hang the processor, or any parts of the system.

Veneer

In the context of the ARM architecture, a small block of code used with subroutine calls when there is a requirement to change processor state or branch to an address that cannot be reached in the current processor state.

VFP

A standard for floating-point coprocessors where several data values can be processed by a single instruction.

VLSI

Very Large Scale Integration.

Watch

In RealView Debugger, a watch is a variable or expression that you require the debugger to display at every step or breakpoint so that you can see how its value changes. The Watch pane is part of the RealView Debugger Code window. It displays the watchpoints you have defined.

Watchpoint

In RealView Development Suite, this is a hardware breakpoint.

Word

In the context of the ARM architecture, a word holds a value held in four contiguous bytes. A 32-bit unit of information. Contents are taken as being an unsigned integer unless otherwise stated.

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