Table of Contents
To trigger when expected data does not appear when requested
To trigger when expected data does not appear when
requested
Go to the timing analyzer's Trigger menu.
1
Define a term called DATA to represent the expected data, the Edge1
2
term to represent the chip select line of the remote device, and the
Timer1 term to identify the time limit for receiving expected data.
You can rename the Edge1 and Timer1 terms to match the problem domain,
for example, to REM_SEL and ACK_TIME.
Under Timing Sequence Levels, enter the following sequence
3
specification:
•
Find "REM_SEL" Occurs "1" Else on "no state" go to level "1"
•
TRIGGER on "ACK_TIME > 16.00 µs" Occurs "1" Else on "DATA" go to
level "1"
You will need to start ACK_TIME timer (Timer1) upon entering this state.
You do this using the Timer Control field in the menu for sequence level 2.
This sequence specification causes the analyzer to trigger when the data does
not occur in 16 µs or less. If it does occur within 16 µs, the sequence restarts.
Specifications of this type are useful in finding intermittent problems. You
can set up and run the trace, then cycle the system through temperature and
voltage variations, using automatic equipment if necessary. The failure will be
captured and saved for later review.
Triggering when Data not Returned
Single-Machine Trigger Examples
6-17
Table of Contents
Troubleshooting
