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Increase delay between Radio Event and CPU cycle

Locky

I am using S110 7.1.0 which I know has the ability to unblock the CPU during Radio Event. However I would like to do the opposite and increase the time between a Radio event and a CPU cycle. The reason is for Battery measurement accuracy. I cannot guarantee that when my app_timer expires to trigger battery measurements, that it doesn't measure right after a Radio Event. Since the Radio Event will cause the voltage to drop, this drop could persist during the battery measurement causing a falsely low measurement. In an effort to increase the consistency of Battery Measurements, I would like to increase the time between a Radio Event and CPU cycles. Is this possible? If there is another method to making a Battery Measurement more accurate I'm all ears.

Thanks for the help guys,

-K

p.s. I am using averaging across several measurements, but still find the Battery Level report far lower then expect values. I even removed the battery to measure its capacity/level/IR is much higher than what the battery service is reporting.

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    You can use radio notifications in order to get a guaranteed distance of an application action from a radio event. A radio notification can trigger right after a radio event or with a predefined distance before a radio event. Radio notificaitons are documented in the S110 Softdevice Specificaiton v1.3, chapter 7. Here is an radio notifications example that runs with nRF51 SDK 6.1.0

    ble_app_template_with_radio_notification.zip

    Yes, the voltage will drop during a radio event as the radio uses more current than anything else on the chip. The voltage will drop more if the battery has large internal resistance. Lower quality batteries usually have higher internal resistance, which creates bigger voltage drop during a radio event. The most realistic time to measure the battery voltage is actually during a radio event because then the voltage is the lowest, but as you say, then the voltage may perhaps not be very stable.

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    You can use radio notifications in order to get a guaranteed distance of an application action from a radio event. A radio notification can trigger right after a radio event or with a predefined distance before a radio event. Radio notificaitons are documented in the S110 Softdevice Specificaiton v1.3, chapter 7. Here is an radio notifications example that runs with nRF51 SDK 6.1.0

    ble_app_template_with_radio_notification.zip

    Yes, the voltage will drop during a radio event as the radio uses more current than anything else on the chip. The voltage will drop more if the battery has large internal resistance. Lower quality batteries usually have higher internal resistance, which creates bigger voltage drop during a radio event. The most realistic time to measure the battery voltage is actually during a radio event because then the voltage is the lowest, but as you say, then the voltage may perhaps not be very stable.

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