Getting Started with RealView Debugger
ARM DUI 0181B Copyright ©2002 ARM Limited. All rights reserved. 3-7
3.3 Working with memory
Before you load an image, you might have to define memory settings. This depends on
the debug target you are using to run your image. For example, if you are using the
default ARMulator to simulate an ARM processor, setting the value of top of memory
is not appropriate.
Where appropriate, defining memory gives you full access to all the memory on your
debug target. RealView Debugger enables you to do this in different ways, for example
using an include file, or defining the memory map as part of your target configuration
settings. These options are described in detail in RealView Debugger v1.6 User Guide.
Note
In the example in this section, you set up memory manually for the current session.
Target memory settings defined in this way are only temporary and are lost when you
exit RealView Debugger.
This section describes how to set up memory:
•Setting top of memory and stack values
•Setting top of memory for a session on page 3-8.
3.3.1 Setting top of memory and stack values
The top of memory variable is used to enable the semihosting mechanism to return the
top of stack and heap. If you are not using an ARM-based target, or if your target does
not use semihosting, this is ignored.
If you do not set these values, RealView Debugger uses default settings that are
dependent on the debug target. For ARM processors the default value used for top of
memory is
0x20000
.
When you first connect to an ARM-based target, RealView Debugger displays a
warning message in the Cmd tab:
Warning: No stack/heap or top of memory defined - using defaults.
You can set permanent values for top of memory, stack, and heap, using the Connection
Properties window. Configure your debug target and define these settings so that they
are used whenever you connect. See the chapter describing configuring custom targets
in RealView Debugger v1.6 Target Configuration Guide for an example of how to do
this.