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DDisk Cursor Units Toggle
When a DDisk file (longer than 1024 samples) or static file (1024 samples) is open and in waveform display mode (Spectrum and Sgram off), this button allows the solid and dotted cursor position readouts to display X values in the units set via the DDisk Units buttons above it, relative to the start of the file instead of the normal start of the display frame.
One handy use for this control is when you have a long file with a separate list of event times, perhaps saved in a log file or Notes, and you want to scroll through the file to view each event. The DDisk Position readout at the lower right of the display area can be monitored as you scroll, until you are close to the recorded event time. Then the cursors can be dragged until the readout matches the event time.
Alternatively, you can enter the time directly in the DDisk Position control to jump directly to the event, then scroll back and use the cursor readouts to view whatever led to the onset of the event.
When the button is on and the units are are active, the solid and dotted position readouts will have pink backgrounds. In this mode, you can still use the small up/down buttons at the right end of each readout to scroll the cursor position, but you can't use direct entry.
For open DDisk files, you can change the units used without opening the DDisk control dialog by clicking the DDisk Position readout units button. Each click will scroll to the next units option. Alternatively, the ALT+SHIFT+D hot-key combination will scroll through the units.
For static files the DDisk Position readout isn't present, so you will either need to open the dialog, or use the hot-keys, both for scrolling the units and for toggling DDisk Cursor Units mode.
Note that when the Units are HMS, Local, or UTC, the seconds resolution is reduced to 3 decimal places (HH:MM:SS.nnn) to fit in the readout window. At the default sound card sample rate of 48000 Hz each sample is only 20.833 microseconds, or 0.000020833 seconds. You may thus have to move the cursor by as much as 48 samples to see a change in the readout value of 1 millisecond.
Important: As noted, when Cursor Units mode is active the readouts show values relative to the start of the file. For Bytes, Samples, Seconds, and HMS the start is always 0. But for Local and UTC the start is a clock time, which Daqarta derives by noting the time the file was saved and computing backwards to the start time from the sample rate and the number of samples. That means if you modify the file, such as by adding Notes and re-saving under the same name, the Local and UTC times will be wrong.
DDiskCurs=1 sets Cursor Units on, DDiskCurs=0 sets it off, and DDiskCurs=x toggles the current state.
DDiskCurs=A sets the state according to variable A (which may be an integer, float, or fixed-point variable), where an absolute value of 0.5 or more will set Cursor Units on, and anything less will set it off.
UA=DDiskCurs will set UA with the current 0 or 1 Cursor Units state.
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