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4.9. Additional Waveform Information The Options menu also includes possibilities to obtain additional information about the waveform. In both cases described below the display will be updated after each acquisition. The “Show Segment Timestamps” option shows a display like the one below: It gives you the information needed to better understand the trigger times of the individual segments of an acquisition. By definition the first trigger of an acquisition occurs at t1=0.0. There are two columns for each digitizer. For the n’th row, the first column contains the difference tn – tn-1 and the second column contains tn. The top line contains the average value of the tn in the left column and the standard deviation of the tn in the right one. The times are in ps. The “Show Parameters” option activates a display of pulse parameters for each active channel. Inactive channels will have parameter values of 0.0. The parameters will be calculated in a model in which the distribution of measured voltages has two distinct peaks. If this condition is not satisfied the results will be unreliable. 4.10. Display Features Display features in the Options menu include items for • turning the waveform display off (by de-selecting “Display Waveforms”), • overlaying segments of a sequence, • connecting displayed data points, • modifying the display refresh rate, • displaying the internal temperature of the currently selected module 4.11. Command Line Switches When starting the AcqirisLive application, the executable's name in the command line can be followed by one or more switches to change the running conditions. Syntax The syntax of the command line is the following: path\AcqirisLive.exe options where options are chosen from the following list [-a][-b][-B][-c][-d][-h][-i][-l][-m][-n][-p][-s][t][-v][-x] Available Switches List of available switches: -a start in Averager mode -b Buffer size for large waveforms -B Number of banks for SMAR mode -c no initial calibration -d use DMA for data transfers (default) -h high priority process (default) -i use acquisition interrupts -l low priority process -m medium priority process -n no DMA for data transfers -p Use acquisition polling -r start in Transient Recorder (digitizer) mode -s simulation mode -t temperature update off -v show acquisition state -x disable automatic multi-instruments Operation Mode Acqiris averagers can be operated in Averager Mode or in standard Digitizer Mode. AcqirisLive operates in either mode, but since these are mutually exclusive, only instruments that support the chosen mode are accessible in any given mode. E.g. only averagers are accessible in Averager Mode, while both digitizers and averagers are accessible in Digitizer Mode. The operation mode can be switched within the application. By default, AcqirisLive starts in Digitizer Mode. Buffer size Upon startup of the application, the available physical memory on the computer is checked. The total data buffer size is then limited to the available memory minus 10% of the total memory. It is also possible to limit the total data buffer size to a fixed value with the -bn option (where n is the limit in MB, e.g. -b200 will limit the buffer to 200 MB). The data buffer is then shared among the active channels. When the total acquisition memory (sum over all active channels) exceeds the data buffer size limit, readout of the data will be partial. The special operation modes such as Segments Average, Average, Digital Filter and FFT are not supported with partial data readout. Partial readout is controlled with the Very Long Memory panel (menu Options ->Very Long Memory...). The first segment and the first sample to read out can be specified. Note that if the buffer is large enough for at least 1 full segment, only full segments will be read (i.e. first sample control is ignored). When saving data to file, you will be prompted for a maximum number of segments per file. Banks for SMAR Some of the 10-bit Family modules are capable of acquiring data and being read out simultaneously. The -Bn option allows the internal memory of the digitizer to be divided into n banks. To observe the improved acquisition trigger rate achievable in this mode it is suggested to set up the desired conditions and then turn the event display off. The trigger out signal can be used to monitor the trigger rate; an interval width trigger can be used to check if triggers are missing. Calibration Before operation, the instruments must undergo an internal calibration. As this calibration can only proceed sequentially for each channel, the initialization time of AcqirisLive can become significant for systems with many channels. Therefore, it can sometimes be desirable to be able to start the application quickly by skipping the calibration (which must then be done "manually" before collecting correct data). DMA Data Transfers By default, data transfers on the PCI bus between the digitizer memory and the PC are done in DMA (Direct Memory Access) mod...

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