ARM DS-5 Using the Debug Hardware Configuration Utilities

Configuring debug hardware for GDB9.9 Connections to a target without built-in GDB support (RVI-GDB)These are connections to targets where no GDB stub has been built into the target application,or when you want to perform halt-mode debugging. Connections of this type use the built-inGDB protocol interpreter of debug hardware to control the CPU directly, and are referred to asRVI-GDB connections. When you want to examine the internal state of the CPU (such asregisters, memory, and variables), the image on the target stops executing. After examining therequired state, you must start the image again. The following figure shows the configuration:Debug hosttelnetDebug unitConfigurationMechanismSet up JTAGscan chainTargetGDB4000, 4001,...GDB protocolGDB protocolinterpreterJTAGrun controlApplicationFigure 9-1 RVI-GDB connectionsNoteGDB does not support Semihosting over JTAG. Therefore, any prompts and messages that areoutput by the application cannot be displayed in your debugger.9.9.1 RVI-GDB ScenariosUse the RVI-GDB connection method to:• perform run and stop debugging of a single ARM processor• perform run and stop debugging with GDB at the same time as debugging the application.That is, for example, if connecting to a target with a GDB stub (Target-GDB connections),or if your target application requires TCP/IP communication with the debug host(Target-GDB-Virtual Ethernet connections).NoteWhen the image stops, so does the handling of interrupt routines. This might not always bedesirable when debugging a real-time system.9.9.2 PrerequisitesTo use the RVI-GDB connection method, it is recommended that you compile your targetapplication using a GNU toolchain for ARM architectures.9.9.3 ProcedureIf your application does not have GDB support linked-in, you can use the GDB protocol builtinto the debug hardware unit to debug your application. However, this controls the CPU directly,and the CPU stops whenever you want to examine its internal state.To debug an application through a RVI-GDB connection:1. Power-up your target hardware and debug hardware unit.ARM DUI 0498F Copyright © 2010-2012 ARM. All rights reserved. 9-11ID021112Non-Confidential