Tornado

Tornado 2.0
User’s Guide
attach system
Switches the target connection into system mode (if supported by the target
agent) and stops the entire target system.
Or, select Target>Attach System from the CrossWind menu.
The response to a successful attach system is output similar to the following:
(gdb) attach system
Attaching to system.
0x5b58 in wdbSuspendSystemHere ()
Once in system mode, the entire target system stops. In the example above, the
system stopped in wdbSuspendSystemHere( ), the normal suspension point after
attach system.
! CAUTION: Not all targets support system mode, because the BSP must include a
special driver for that purpose (see 2.5 Host-Target Communication Configuration,
p.31). If your target does not support system mode, attempting to use attach
system produces an error.
7.5.2 Thread Facilities in System Mode
In system mode, the GDB thread-debugging facilities become useful. A thread is
the general term for processes with some independent context, but a shared
address space. In VxWorks, each task is a thread; the system context (including
ISRs and drivers) is also a thread. GDB identifies each thread with a thread ID, a
single arbitrary number internal to the debugger.
You can use the following GDB commands to manage thread context.
info threads
Displays summary information (including thread ID) for every thread in the
target system.
thread idNo
Selects the specified thread as the current thread.
break linespec thread idNo
Sets a breakpoint affecting only the specified thread.
For a general description of these commands, see GDB User’s Guide: Debugging
Programs with Multiple Threads. The sections below discuss the thread commands
in the context of debugging a VxWorks target in system mode.
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