4 years, 5 months ago.

Why are sensor values not stable when I use BLE ?

Why are sensor values not stable when I use BLE ?

I'm new to programming and mbed. I want to send sensor values to iOS with BLE and I use MPU-9250 and HRM1017r3.

I tried some examples for them. MPU-9250 https://developer.mbed.org/components/MPU-9250/ works well and HRM1017 https://developer.mbed.org/teams/Switch-Science/code/BLE_HTM_HRM1017/ , too.

I made a new project and integrated them. And I was able to send sensor values to iOS. But Sensor values were weird.

That's why I commented out about BLE and it worked well. (MPU-9250's values were not weird. It was really stable) But if I initialize BLE (e.g. ble.init()) it doesn't work well. (MPU-9250's values were weird. It was like switching high and low. i.e. 100, 21, 143, 120, 32, 132, 100...)

I think that there is a problem around i2c or clock. But I didn't know how to solve it. Please help me.

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