Runtime environment: 1.IC:52840QIAA ； 2.SOFTDEVICE:s140_nrf52840_5.0.0-2.alpha_softdevice.hex Development: PWM signals of 10 groups of adjustable frequency and width in 30 channels IO output. Adjustment range: frequency 1 ～ 120Hz, width 50 ～ 400us. Result: Without writing SOFTDEVICE, frequency and width of 10 groups of output are stable. After writing SOFTDEVICE, frequency of 10 groups of output is stable, but when we tested random IO output signal, we found width would increase less than 100us. Video 1: After writing SOFTDEVICE, pulse width is changing when Bluetooth is working; Video 2: Without writing SOFTDEVICE, pulse width is accurate and stable when 52840 is working only as SCM.

This post is older than 2 years and might not be relevant anymore
More Info: Consider searching for newer posts

Writing SOFTDEVICE makes signal width increases

pump20 over 6 years ago

Runtime environment:

1.IC:52840QIAA；

2.SOFTDEVICE:s140_nrf52840_5.0.0-2.alpha_softdevice.hex

Development:

PWM signals of 10 groups of adjustable frequency and width in 30 channels IO output.
Adjustment range: frequency 1～120Hz, width 50～400us.

Result:

Without writing SOFTDEVICE, frequency and width of 10 groups of output are stable.
After writing SOFTDEVICE, frequency of 10 groups of output is stable, but when we tested random IO output signal, we found width would increase less than 100us.

Video 1: After writing SOFTDEVICE, pulse width is changing when Bluetooth is working;

Video 2: Without writing SOFTDEVICE, pulse width is accurate and stable when 52840 is working only as SCM.