How to use sd_rand_application ?? or use Random number with NRF51 ?

RE: How to use sd_rand_application ?? or use Random number with NRF51 ?

Daniel T. Lee — Thu, 23 Mar 2017 08:05:16 GMT

Thanks! really, But It would be really helpful if API Documentation's explanation gets little bit more specific.

Such as It would need some time to full random numbers in buffers, so User might to wait little bit before calling sd_rand_application_bytes_available_get(...).

RE: How to use sd_rand_application ?? or use Random number with NRF51 ?

Sigurd — Wed, 22 Mar 2017 11:53:35 GMT

Hi,

Q1: But Actually I can't find any appropriate document for this function. Is there any document for this function's usage?

A1: You can find the API documentation here.

Q2: Does this function needs for NRF_RNG_Driver enabled? do I have to include nrf_drv_rng.c to use this function?

A2: This is a SoftDevice API function, you don’t need to enable NRF_RNG_Driver. And you don’t need to include nrf_drv_rng.c. You only need to have enabled the SoftDevice.

Your code looks correct, but if you call the function very close to the time you enable the SoftDevice, the SoftDevice hasn't had enough time to fill the buffer of random numbers. It takes some time after the SoftDevice is enabled to the buffer with random numbers is filled. Wait a couple of milliseconds, and call sd_rand_application_bytes_available_get(..) again until you have available bytes in the pool.

RE: How to use sd_rand_application ?? or use Random number with NRF51 ?

Alex — Tue, 21 Mar 2017 09:27:07 GMT

Ah, sorry, you call SD functions directly.

RE: How to use sd_rand_application ?? or use Random number with NRF51 ?

Daniel T. Lee — Tue, 21 Mar 2017 09:22:37 GMT

do I have to use nrf_drv_rng even if I don't use RNG?

OR does sd_rand_application is consisted of RNG?

RE: How to use sd_rand_application ?? or use Random number with NRF51 ?

Alex — Tue, 21 Mar 2017 09:19:25 GMT

Have you called nrf_drv_rng_init(NULL) before running code above?