HP 64783A, User Manual

Page: 652 / 816

b>th;ts
Emulation trace halted
--- Emulation Trace Status ---
User trace halted <- trace status
Arm ignored
Trigger not in memory
Arm to trigger ?
States 0 (0) ?..? <- number of states captured
Sequence term 2
Occurrence left 1
b>
If the trace status indicates that the trace was halted, look at the number of states
collected to decide how many bus cycles were executed. If the status indicates that
the user trace was completed, a large number of states were executed. If this is the
case, it may help to take another trace to see if bus cycles are still being executed.
Again, view the trace status to determine if bus cycles are executing.
If the "p>" prompt remains after target powerup, check:
•
mechanical installation of the probe.
•
blown fuses.
•
target system power supply voltage.
If the prompt is "c>", mechanical installation may be causing the problem, but the
most likely cause is a problem with the clock. Check clock quality. Look at the
voltage levels, edges, and duty cycle. If you suspect the clock, compare it to the
target system clock without the emulator. If there is a significant difference, you
may need to adjust the target system terminations to account for the emulator’s
termination.
If the prompt is "r>", either the target system never released reset, or the target
system reset itself because of some program error condition. If no bus cycles were
captured by the analyzer, the target system never released reset. You need to find
out which conditions must occur to release reset, and then investigate these
conditions to determine why reset isn’t being released.
An example of a failure to release reset might be a multicard system where the
master card starts the slave cards after verifying that they are installed in the system
by reading checksums from their ROMs. If a checksum is not read correctly, reset
to the associated slave card is not released. If the emulator interfered with the
reading of the checksum, then reset would not be released.
Chapter 18: Connecting the Emulator to a Target System
Verifying Operation Of The Emulator In Your Target System
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