ARM ARM DUI 0137A manual CPU register access, Nonstop startup

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Debugging with RMHost

Note

This workaround is performed only if you have built RMTarget to support the

ExecuteCode packet (see RM_OPT_EXECUTECODE in the building chapter of the ARM

RMTarget Integration Guide).

It is recommended that you build RMTarget with support for either or both of the following:

word and/or halfword writes (see RM_OPT_WRITEWORDS and RM_OPT_WRITEHALFWORD in

the building chapter of the ARM RMTarget Integration Guide)

the ExecuteCode packet (see RM_OPT_EXECUTECODE in the building chapter of the ARM RMTarget Integration Guide).

3.1.3CPU register access

CPU registers can be read while your application is stopped. It is not possible to read/write CPU registers while your application is running.

Access to specific registers can be restricted using the register accessibility block built into RMTarget (see the RM_RegisterAccess section of the API chapter in the ARM RMTarget Integration Guide). If this is done, certain registers can become unreadable or unwritable. If marked as unreadable, AXD does not return an error, but it displays register values as zero.

Read and write access must not be removed from the program counter (pc) if start-stop debugging (such as the ability to set breakpoints and stop the application) is to be supported. Similarly, access to the unbanked registers must not be removed if semihosting is to be supported.

3.1.4Nonstop startup

When your application is running, and you establish connection to RMHost, your target application is typically stopped. With RMHost, you can select a mode that allows your application to continue to run when you establish connection to RMHost. If you connect using this method, you can then check the state of your application without having to stop it. You can do this using background memory accesses, which are supported by RMHost (see Background memory access on page 33).

This feature is enabled when you select the option ATTACH: Connect according to target properties. For more details, see the step on configuring the interface in Procedure for connecting to RMHost using AXD on page 22.

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Copyright © 2000 ARM Limited. All rights reserved.. All rights reserved.

ARM DUI 0137A

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Contents ARM RMHost ARM RMHost User GuideUser Guide Chapter Debugging with RMHostContents Preface About this book onIntended audience Using this bookAbout this book Typographical conventionsFurther reading ARM publicationsOther publications Feedback Feedback on RMHostFeedback on this book ARM DUI 0137A Overview of RMHost About RMHost on RMHost requirements onAbout RMHost Application/RTOSOverview of RMHost RMHost requirements RMHost packageConnecting to RMHost Procedure for connecting to RMHost using AXD Debuggers chapter of the Multi-ICE User Guide Select Configure Interface from the Options menu Configure interface dialog boxDescribes how to do this RealMonitor Configuration dialog box Jtag controller search dialog box Deselect the the option Fetch module information from target Cancel No pc write access messageNo pc read access message AXD connection messages Lines 2212 Debugging with RMHost Debugging with RMHost Nonstop debugBackground memory access CPU register access Nonstop startupProfiling Data messagingSemihosting Debugging with RMHost Error messages RDITarget does not include an ARM processor Memory map forbids reading from location RMHost could not load the specified Jtag controller Other messages from RMHost Yes312 Using RMHost with Trace Debug Tools AsicConfiguring AXD to enable tracing with RMHost Performance of RMHost with TDTSelect Debugger Internals from the System Views menu Index RmoptsdminfoRmoptdatalogging Rmoptgetpc