User´s Manual - I+ME ACTIA GmbH

Buffer Handling
CAT uses the serial COM ports to communicate with the PC. So it is not possible to transfer and store
the bus traffic directly in real time on the PC. Not to miss any CAN message CAT Hardware provides
enough buffer space to store about 50,000 CAN frames.
The buffer is build up as a circular buffer. When logging more than 50,000 frames the first entries will
be overwritten (No. of Overflows is displayed in Status Bar). Use the filter possibilities or stop logging
by time to assure not to loose data by overwriting them.
The total 50.000 frame buffer on CAT Hardware contains two parts:
- - the Logging Buffer,
The logging buffer contains all CAN data that are received from the bus (unless there is no filter) and the
data that are transmitted by CAT.
- - the Diagnostic Buffer.
The diagnostic buffer contains the diagnostic data that are received from the bus (unless there is no filter)
and the data that are transmitted by CAT.
The user can configure how much of the total 50.000 frame space is used for the Logging and how
much for the Diagnostic Buffer. See Buffer Setup for details.
Being Online the Buffer content is first stored only on the Hardware. Only after uploading the buffer
there is access to this data in the Offline respectively Diagnostic Offline mode.
! If the user disconnects the Hardware from the Power Supply (by disconnecting the CAN
adapter cable) and has not uploaded the buffer the user will loose the logged data!
Analyzing Buffer content
After being Online the Buffer has to be uploaded before there is access to the logged data. Otherwise
the buffer data are still displayed that has been uploaded before. This could be helpful if a short review
of the last test is wished before opening the new results.
Being Offline, after uploading the buffer it is possible to Export Logging Buffer, respectively to Export
Diagnostic Buffer to save the results of a test. The created files are readable by Excel so the buffer
content can be analyzed using the typical Excel features.
Otherwise the user can scroll through the buffer using in CAT Offline respectively Diagnostic Offline
Mode the:
- Trace List View
In the Trace List View every buffer entry is visible.
- Diagnostic Output
In the Diagnostic Output every diagnostic related buffer entry is visible.
- Frame List View
In the Frame List View only the buffer entries are visible that are defined to be displayed.
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Note: There is no visible scrolling by changing the position of the entries only the data
change. Have a look to the Status Bar where the time is changing.
- Signal List View
In the Signal List View only the buffer entries are visible that are defined to be displayed. Each time
the same signal has been received again the color of the value character switches from black to red
and vice versa.