The figure below displays the recorder parameter settings tab.
There are the following items in the menu:
- Ts min record - list that allows selecting the minimum sampling period, if less recording is disabled. In this case the minimum period equal to 10 uS (Fs =100 KHz) is set, i.e. sampling periods of 9 uS �5 uS (Fs =111 KHz...200 KHz) cannot be selected. Ts min record is determined by experiment on the basis of several measurements. For example, it is first necessary to set Ts min record = 5 uS, i.e. enable recording within any sampling period and perform the measurements for Ts=5 uS (Fs =200 KHz) as well, if there is not signal distortion it means that your computer and operating system can transfer data at the maximum speed. If there is distortion you need to increase the sampling period, e.g. up to 6 uS (167 KHz) and perform the measurements once again and etc. Upon determining the sampling period without distortion in the measurement results, it is expedient to set it as minimum. So, this option just disables to set the sampling periods if you consider that within those there is distortion while reading. What are the reasons?
- Ts min show - list that allows selecting the minimum sampling period if less the waveform plotting immediately in the record mode is disabled. The point of disable or enable plotting within measurements is that within the sampling period e.g. of 5 uS (200 KHz) each second 200 thousand dots are to be plotted on the screen, but it is out capabilities of even advanced computers and at this plotting rate it will be an obscure picture on the screen (waveform will be just leaping). But on the other hand, within the large sampling periods (less frequency) displaying the measurement results immediately in the recording mode enables to analyze the signal variation dynamics visually and probably stop recording under certain conditions. In addition, it is necessary to note that Ts min show is more or less dependent on a number of the recorded samples, e.g. in Athlon XP 1700, 512M you can record waveform with Ts min show for 20 ms (50 KHz) but in 3-5 minutes of recording (about 10 million samples) time for the next waveform portion plotting sufficiently increases due to necessity to calculate the additional diagram parameters.
- Disable averaging (Ts<10 ms) - this flag disables to decrease the sampling period (increase frequency) and perform averaging for several samples (arithmetic average). This flag is active only for the periods less than 10 ms (frequency higher than 100 Hz), with longer sampling periods (less frequency) averaging will be turned on automatically. When operating within the sampling periods close to Ts min show and Ts min record, it is recommended to disable averaging. In case if the sampling period is much longer than Ts min show, it is recommended to enable averaging based on considerations that the microcontroller data are read for 409 samples (512/1.25 (10 bits)) at a time and then plotting starts, e.g. for the sampling period of 10 ms (100) plotting will be performed every 409 * 0.01 = 4 seconds and if averaging is enabled and Ts min show is set, e.g. to 1 ms (1 KHz, i.e. when artificially limiting the maximum increase of sampling frequency up to 1 KHz) then plotting will be performed every 409 * 0.001 = 0.4 seconds for 409/10=50 samples, at that it will be much convenient to view the waveform variation.
- Scaling by Ts - enables the signal compression/stretch when changing the sampling period. The point is only when the mass signal compression is necessary if you need to view the general waveform pattern.
- Ask for color when new marker adds - if the flag is set, then upon adding (creating) a new marker the color settings dialog window automatically opens.
- Ask for comments when new marker adds - if the flag is set, then upon adding (creating) a new marker the comments input dialog window automatically opens.
- Fast waveform plotting - if the flag is set, then the measurement results plotting is performed with faster simplified functions. In the operating system Windows 98/Me the result show accuracy can be reduced in some way.
- Do not show intermediate (merging) points - if the flag is set, then when plotting the points with the same coordinate in pixels on the screen are not displayed. Waveform plotting will be much faster if a large waveform portion is shown concurrently, e.g. within mass compression but if there is the abrupt signal variation then it will be shown incorrectly within mass compression.
- Do not show the total record time during the recording - if the flag is set and the sampling period is fixed at which display of the measurement results is disabled immediately within the waveform record then the total record time will not be shown during the recording. At that, if the autostop time is not fixed, then the total record time has to be calculated by any external timer. It is recommended to set this flag at the maximum frequency and in low-speed computers, as the very bar plotting with the total time requires greater resources of CPU than the next data processing.
- Dynamic memory allocation (on demand) - if the flag is set, and autostop is not set, then the memory for the waveform samples storage is allocated immediately in the waveform record mode for which greater resources are consumed and the maximum sampling frequency for the low-speed computers decreases. If the flag is not set, then before start the program tries to allocate all available memory but at most 256M for which the waveform record starts with delay. If you know or can estimate the exact interval to record waveform it is strictly recommended to set the autostop time as it will enable program to allocate the necessary memory early (there is no excess memory allotment) before the record process starts.