wal...@edenconceptsllc.com schrieb am Donnerstag, 15. April 2021 um 18:35:20 UTC+2:
> So, STEPENABLE lets me enable the steps that I want to be executed. (I > missed that concept before.) > > So if I had an application that had a sensor A that needs to be read every > 10ms and sensor B that only needs to be read every minute, I could wire > channel 1 to sensor A and assign it to step 1 and wire channel 2 to sensor > B and assign it to step 2. > > Then at startup, when I want to read both sensors, I enable steps 1 and 2 > but not 3-16. This saves time on the read as channels 3-7 aren't needed > and steps 3-16 aren't needed so I don't use them. Then after the initial > read when I don't need to read sensor B until a minute passes, I can change > STEPENABLE so only step 1 is enabled and execute a read every 10 ms. Only > sensor A would be read. Then at one minute intervals, I change STEPENABLE > so steps 1 & 2 are enabled and when read is triggered, sensors A and B are > read. > There're 17 steps, one charge step and 16 sample steps. Each step configures not only the multiplexer (chanel 0-7), but also an open delay and a sample delay, as well as an avaraging number. That's explained at AdcUdt::setStep() <https://users.freebasic-portal.de/tjf/Projekte/libpruio/doc/html/class_adc_udt.html#a243d91f0b7b7a29ada9bc14364c3284f>, including a hint where to find further information in the ARM TRM. In order to write to the STEPENABLE register you've to stop the sequencer, write the new value and restart the sequencer again. This is 3 times L3 operation, which need at least 3 PRU cycles each (perhaps more in case of heavy travel). How do you what to ensure accurate ADC timing? The outnumber of step registers isn't thought of macroscopic asymmetry (in your case sample channel A and B at 10 ms and ignore the B value for a minute). It's made for microscopic asymmetry, ie when you want to sample A twice as often as B. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to beagleboard+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/def726b2-31f2-469b-a9fc-70fc429ffa59n%40googlegroups.com.
