+@item @b{Watchdog Timers}...
+Watchog timers are typically used to automatically reset systems if
+some application task doesn't periodically reset the timer. (The
+assumption is that the system has locked up if the task can't run.)
+When a JTAG debugger halts the system, that task won't be able to run
+and reset the timer ... potentially causing resets in the middle of
+your debug sessions.
+
+It's rarely a good idea to disable such watchdogs, since their usage
+needs to be debugged just like all other parts of your firmware.
+That might however be your only option.
+
+Look instead for chip-specific ways to stop the watchdog from counting
+while the system is in a debug halt state. It may be simplest to set
+that non-counting mode in your debugger startup scripts. You may however
+need a different approach when, for example, a motor could be physically
+damaged by firmware remaining inactive in a debug halt state. That might
+involve a type of firmware mode where that "non-counting" mode is disabled
+at the beginning then re-enabled at the end; a watchdog reset might fire
+and complicate the debug session, but hardware (or people) would be
+protected.@footnote{Note that many systems support a "monitor mode" debug
+that is a somewhat cleaner way to address such issues. You can think of
+it as only halting part of the system, maybe just one task,
+instead of the whole thing.
+At this writing, January 2010, OpenOCD based debugging does not support
+monitor mode debug, only "halt mode" debug.}
+
+@item @b{ARM Semihosting}...
+@cindex ARM semihosting
+When linked with a special runtime library provided with many
+toolchains@footnote{See chapter 8 "Semihosting" in
+@uref{http://infocenter.arm.com/help/topic/com.arm.doc.dui0203i/DUI0203I_rvct_developer_guide.pdf,
+ARM DUI 0203I}, the "RealView Compilation Tools Developer Guide".
+The CodeSourcery EABI toolchain also includes a semihosting library.},
+your target code can use I/O facilities on the debug host. That library
+provides a small set of system calls which are handled by OpenOCD.
+It can let the debugger provide your system console and a file system,
+helping with early debugging or providing a more capable environment
+for sometimes-complex tasks like installing system firmware onto
+NAND or SPI flash.
+