Always check the trace buffer specs of any in circuit emulator. Cheaper
emulators don't have trace buffers at all; some middle priced emulators
have trace buffers, but only allow liner recording. The real thing will
allow complex triggering (including external lines) that can toggle the
trace on and off. This allows you to (for example) watch the critical
part of an interrupt routine that only screws up once every 30 hours,
stop on the screwup, and relate the last bunch of interrupt executions
to the crash. If you had to record all of the execution states for the
whole test, you would need a real state (RI or NH?) to hold the trace
buffer.

-- Tom Rogers  VP-R&D  Time Tech Inc.