VL53L1X - Timing budget and intermeasurement time

[VHavl.1]

Hi,

I´ve been asked for starting new topic for this question.

I have general question about speed - in manual, there is line about timing budget which is from 20ms -> 50Hz, but there is InterMeasurement time which is needed to be at least timingBuget + 4ms so single measurement takes (timingBudget + InterMeasurementTime + 4ms) - the measurement time is in this standard approach 25Hz? I know that there is some walkaround for shorter distances but I´m trying to solve this for long range measurements.

I´ve get response in another topic:

the intermeasurement time is the time from the start of one ranging operation to the next. if you want to go as fast as you can simply do not set it. The next range will start immediately. But if you do set it - presumably to put some dead time between each range you have to understand that the clock that manages the timing budget is different from the one that manages the intermeasurement period. If you put the two numbers too close to each other, your IM clock might tick over just BEFORE the timing budget clock. In this case the system will wait until the next IM period. So to be safe, if you use the IM clock make it a bit longer than the TB clock. 4ms is a safe distance.

Thank you for your reply. Intermeasurement time is showed in the manual but its little bit confusing (I didn´t notice smalle font under the picture).

I would like to ask something about setting new ROI. If there is Timing budget = 20ms and Intermeasurement budget = 25ms I have 5 ms for changing the ROI? So the new ROI will be active with new measurement? Is there any option to start measuring in One shot mode, So I would measure one ROI, change the ROI, start new measurement etc?

Final question - VL53L1X_StopRanging stops the current measuring in the middle of timing budget or current measurement will be finished (So I need to wait until timing budget timeout)?

Thank you, best regards Vojtech

There is snippet from the manual where I got confused.

[John E KVAM]

The best way to insure the new ROI is effective for the next range is to set it DURING the current range.

Don't wait until the current range is complete. That's too late.

I start the measurement, wait a ms or two, and then change the ROI (for next time). Once you get rolling, change the ROI, just after reading the prior result. It's tricky to keep the ROI one step ahead, but you can do it.