Hi there,
Without Seeing the code, I can’t offer much help.
Yes, There is an Interrupts Library and a Timer Library both for Nrf52840 , I don’t have links but you can search here for the examples folks have posted. Sounds like that is what you need.
HTH
GL 
PJ
Hello PJ.
Yes, the example blink_print in the timer library is interesting. But I do not understand the toggle principle.
My timer needs pulse of 1 to 2 ms. Then, in the LOW time, the duration of the next pulse is calculated.
Then, after 8 ms since the beginning of the first pulse, everything happens again.
Could you lease look at that sketch, and give me an indication for the solution?
Kind regards,
Wolfgang
P.S Started 50 years ago with FORTRAN.
Hi there,
LOL, man I vaguely remember some Fortran77 back in the 80"s ? Punch cards too. WOW
The Nrf52840 has Several timers and the PWM’s You can use either.
to achieve the outcome, Check out how Arduino generates Pulses link
Basically set the pulse length, attach an Interrupt, In the ISR reset the timer value start the duty cycle timer with interrupt and rinse and repeat.
like this one, it’s also applicable to Xiao.
HTH
GL PJ
I’ll look at the blink_print time permitting 
and make some comments. 
Thanks for the suggestions,
The TimerOne library looked perfect, but it seems not to work with my Xiao Sense, The examples will not compile…
Tried also to change the frequency of the Servo library. Was not able to change the Refresh Interval to 8000 instead of 20000… Still stuck…
Rgards,
Wolfgang
Hi there,
Have you tried the other BSP? In the board selection Pick the second one. What is the BSP that is NOT compiling? Look at compiler output and see which it is.?
HTH
GL PJ
Hello PJ,
tried both BSPs. Compiler always says "class TimerOne " has no member named ‘initialize’
Rads
Wolfgang
Hi there,
Yes that’s not uncommon for older setups, and that’s for an AVR.
Try this one and you’ll see the Seeed board is called out and supported , BSP 1.0.X
HTH
GL PJ
PS> DO NOT USE Timer (0) ZERO… or 
Hello PJ,
Coming nearer.
Modifying TimerInterruptLEDDemo, I could use one timer for a short blink, following by a second timer for a longer pause.
But this sketch is only in milliseconds, and I need the first timer in microseconds…
Suggestion?
Thanks for your patience,
Wolfgang
Hello PJ,
Is there a way to reset the Bluetooth system? It is only used at the beginning of the sketch, to start the main program.
Regards,
Wolfgang
Hi there,
Great to hear that, There is a learning curve but it’s not Too heavy a lift though.
Here are some ways to stop BLE on an nRF52840:
- Start and stop advertising: Use
sd_ble_gap_adv_start()andsd_ble_gap_adv_stop() - Disconnect from the central: Use
sd_ble_gap_disconnect()while in a connection - Stop scanning with BLE.end(): While the peripheral is off, stop scanning with
BLE.end() - Disable completely the 2.4Ghz radio: After the 52840 has full soft device enabled and ble stack has been run, disable completely the 2.4Ghz radio
HTH
GL PJ
Hello PJ,
the sd commands were not accepted, but “BLE.end” worked!!! Golden Tip!!
Many thanks,
Wolfgang
Result:
Bye,
Wolfgang
Hi there,
SWEET!
Incrementally moving forward… NICE!
GL PJ
good to learn from it. dear.
Hello PJ,
my application allows only 6 milliseconds to measure x and y accelerations.
Using myIMU.readFloatAccelX(), each measurement takes between 651 and 670 microseconds. This allows for 8 measurements, which works, but I would like somewhat more samples. Is there a method to measure x and y at the same time?
Regards,
Wolfgang
Hi there,
Have a look at the data sheet that seems kind of low, If you use High performance mode, Higher clock, probably do better.
HTH
GL PJ
Hello PJ,
tried all the Arduino IMU examples, always >650 µs.
No idea how to modify IMU readings, or what is behind “!2C_MODE”.
Regards,
Wolfgang
Hi there,
What about I2C clock speed or buss speed? any adjustments there?
With out seeing the code , Hard to see where you can gain. What the use case your attempting to satisfy.
HTH
GL PJ
Hello PJ,
To use the acceleration sensors, I just copied the example HighLevelExample, as provided by Arduino.
It does not seem to allow any speed modifications.
Regards,
Wolfgang
Hi there,
Ok , I see. Well I know there’s a limit to the speed of getting the readings, even in the high level examples but seems kinda low. (pretty sure the config reg’s are NOT set to high performance)
imo. I would think using the fifo for example could improve that and also writing the values to memory with a DMA function. lots to see here too, I thought there was an interrupt driven one that yielded better speed.
Can you describe what it is you want to do more concisely as an overview.
is this a realtime app or a data logging situation?
Definitely use the search here for IMU readings etc. to find more solutions.
HTH
GL PJ