Editing In-circuit emulation (section)

== On-chip debugging ==
''On-chip debugging'' is an alternative to in-circuit emulation. It uses a different approach to address a similar goal.

On-chip debugging, often loosely termed as ''Joint Test Action Group'' (JTAG), uses the provision of an additional debugging interface to the live hardware, in the production system. It provides the same features as in-circuit debugging, such as inspection of internal state or variables and may have the ability to set checkpoints, breakpoints and watchpoints. The difference is that this is provided by additional silicon within the production processor, rather than swapping the processor for an off-board debugging emulator.  For this reason, some of the functions of the ICE is changed by the specifications of the processor. An additional JTAG interface is added to the controller board, and this is required on every production system, but as this only requires a few signal pins the extra cost is minimal.  JTAG interfaces were originally developed for, and are still useful for, end of production testing.