11.2.4. Effects of setting a breakpoint

Setting a breakpoint updates the Break/Tracepoints view, if it is visible, and the Output view shows the CLI command used to set the breakpoint:

Effect of memory type on breakpoints

The type of breakpoint set, either software or hardware, is determined by the memory type:

  • Setting breakpoints in source-level view inserts a software instruction breakpoint by default. This is set using a BREAKINSTRUCTION command. RealView Debugger attempts to set a software breakpoint if the code is in RAM.

  • If your code is in ROM or Flash, RealView Debugger sets a hardware breakpoint if one is available. This is set using a BREAKEXECUTION command. An error message is displayed if no such breakpoint is available.

  • If you attempt to set a software breakpoint at an address that you know is in RAM, and RealView Debugger unexpectedly sets a hardware breakpoint or fails, then check the Memory Map tab to see if memory mapping is enabled. If memory mapping is enabled, make sure the memory area of interest is defined as RAM. RealView Debugger always sets a hardware breakpoint in a memory area that is marked as Default Mapping.


In some instances, RealView Debugger fails to set a software breakpoint. This situation can arise when memory mapping is disabled, because RealView Debugger attempts to treat all memory as RAM by default. You can use the failover qualifier with the BREAKINSTRUCTION command to force the software breakpoint to be converted to a hardware breakpoint.

See also

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