User manual

UM0036 EMU3 emulator features
Doc ID 7705 Rev 11 313/385
1. Open the Trace window.
2. Right-click the mouse in the Trace window and select Show/Hide Columns from the
contextual menu. Ensure that you are able to view the Record, Event, Timestamp,
Timestamp Event and TIN (Trigger Input) fields.
3. Go to the record in the Trace window that corresponds to the first event. This record
should have Event 1 in the Event field and a value of 0xF in the TIN field. Note the
value (a) in the Timestamp column for this record on a piece of paper.
4. Go to the last record in the Trace window (that corresponds to the second event). This
record should have Event 2 in the Event field. Note the value (b) in the Timestamp
column for this record.
5. Next, you can search your trace record and count the number of times (n) that the
Restart message was found.
Each time the Restart message occurs, it means that the 30-bit timestamp counter was
filled and automatically reset. A 30-bit counter can measure up to (2
30
- 1) time periods.
Each time period is equal to the inverse of your Time Stamp Clock frequency. For
example, using an internal 20 MHz Time Stamp clock results in a period of 50 ns. So
the 30-bit Time Stamp counter is capable of measuring (2
30
- 1) time periods x 50 ns =
approximately 53.687 seconds. If you are using an external Timestamp clock, you
must recalculate this according to the clock frequency.
So, to have an absolute measurement of the time passed between the two events of
interest, perform this calculation:
a) Multiply n (the number of times the Restart message was found) by 53.687
seconds (or whatever you have calculated as the maximum time measurable by
the 30-bit counter if you are using an external timestamp clock with a frequency
other than 20 MHz).
b) Then add b (the value found in the Timestamp column of the trace record
corresponding to event 2).
c) Finally, subtract c (the value found in the Timestamp column of the trace record
corresponding to event 1).
Then you will have the true time between the two events of interest.
10.4 Using output triggers
Your ST7 EMU3 emulator has two output triggers, OUT1 and OUT2. You can program the
output signals to these triggers using Advanced Breakpoints in STVD.
From within Advanced Breakpoints, you can set a trigger output action with the following
options (schematically represented in Figure 247):
● output a pulse—where a signal of value 1 is sent during exactly one memory cycle.
● toggle—where the signal value is changed from 0 to 1 or from 1 to 0.
● set the output high—where the output signal is set equal to 1.
● set the output low—where the output signal is set equal to 0.
The following sections provide Trigger programming examples to help you learn to use
Advanced Breakpoints to control the sending of signals to the output triggers.