Gage CompuScope 85GC, Hardware Manual And Driver Installation Manual

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20 Multiple Record for CS82GC
Multiple Record for the CompuScope 82GC
Even though the CompactPCI bus allows very fast data throughput to system RAM, there may still be
applications in which data bursts cannot be off-loaded either because of very fast trigger repeat frequency or
because of software limitations.
Multiple Recording allows CompuScope 82GC to capture data on successive triggers and stack it in the on-board
memory. The minimum record size is 256 samples in dual channel mode and 512 samples in single channel
mode. CompuScope 82GC models with 16M acquisition memory provide up to 21,845 records which can be
captured in Multiple Record mode.
The CompuScope 82GC is capable of capturing pre-trigger data in Multiple Record mode. Software can
configure the CompuScope 82GC to capture between 0 to 32K points of pre-trigger data.
GageScope software can display the stacked data as individual acquisitions. Software drivers also provide
support for accessing Multiple Record data.
Once the CompuScope 82GC has finished capturing a Multiple Record segment, the trigger circuitry is
automatically re-armed within 152 (
304 ) sample clock cycles in dual ( single ) channel mode to start looking for
the next trigger. No software intervention is required. This is required to ensure that the necessary pre-trigger
data is acquired. That is, data is acquired during this time, however, the trigger is only enabled once the
pre-trigger data has been recorded.
Figure 15: Multiple Record mode with Pre-Trigger data
Multiple Recording is useful for applications in which a series of bursts of data have to be captured in quick
succession and there is not enough time to off-load the data to the system RAM.
Another situation in which Multiple Recording may be used is when data storage has to be optimized. These are
cases in which only certain portions of the incoming signal are of interest and data capture during the dead time
between successive portions is not useful.
Examples of these situations are radar pulses, ultrasound data, lightning pulses, imaging signals and explosion
testing.