softdevice affecting the IR pulse timing

Question

Hello devzone...
My setup: nRF51422 and S110 peripheral
My setup transmits IR data on reception of Bluetooth data from a central device. I have used PWM for generating IR pulses. It is configured as GPIOTE, the timer compare event toggles the pin. This works fine without the softdevice enabled.
If the softdevice is enabled, it blocks the CPU for sometime to serve the radio events which mess up the IR mark and space timings. I have to start and stop the timer tasks and events at proper intervals. Since softdevice blocks the CPU there is delay which increases the IR data timings.
The IR is an integral part of my application, so i would like to avoid ble events till the application sends IR data.
Any suggestions and design improvements where in i can have a sync between IR and ble?
Can i disable the events from sd for the time IR data is being sent? 
 Thanks..:-)

RK · Accepted Answer

This is discussed here very often, you should search for similar questions, there's lots of good discussion and suggestions out there. 
 You can't stop the softdevice or disable it or block it from working and it will absolutely affect anything interrupt-based. 
 You can use the Multiprotocol Timeslot API to request a limited sized window where you have control of the chip, you'll get called back when your window starts. The max size of the window isn't that long, 100ms, and you have to wait for the softdevice to call you to tell you it's ready. is 100ms at random times enough for you? 
 You can use PPI (there are libraries available) to generate PWMs of different duty cycles, but you still have the problem of turning it on and off or changing the duty cycle which again usually requires interrupts. If you have some flexibility in turning the PWM on and off/changing the duty cycle, you may be able to use PPI for the generation and interrupts for control, if your timing is precise on that too, you won't be able to do what you want. 
 The latest revisions of the chip do allow the CPU to work when the radio is on, but the softdevice still will mess up any precise interrupt-based timing. 
 You can also buy an IR chip which does all the IR generation for you and talks serial or SPI and use that instead. A quick google and I found 3, sure there are more, that may be a better way to do what you want because generating precise waveforms with the softdevice running is .. not really possible.

softdevice affecting the IR pulse timing

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