how much time nRF51822 takes to comeout of reset.

[Anand Ramashetty]

Hi ,

Could anybody share me the details on the time taken by the nRF51822 to comeout from reset state for the below reset input.

1. Wakeup from OFF mode reset
2. Pin reset
3. Soft reset

Regards, Anand

[Hung Bui]

Hi Anand,

You can find the start up time from systemOFF and start up time from power-on at Section 8.2 Power management in the nRF51822 Product Spec.

I did a quick test here with pin reset when in systemON, and it takes about 0.2us faster than from systemOFF. The softreset also take about 2us faster. Please be noted that the startup time in the product spec doesn't mean it the time you get to main() because there is some start-up instruction before the PC get to main() for example the code in arm_startup_nrf51.s, system_nrf51.2

I'm expriencing here it's taking about 241~243us to get to main().

[Anand Ramashetty]

Hi Hung Bui,

Thanks for your answer.

[Hung Bui]

@Anand: if the answer worked for you, please accept it and we can close the case.

[Anand Ramashetty]

Hi Hung Bui,

We can close the close.

FYI. I have raised one more question "How to execute code from RAM on nRF51 using GCC Environment?" Currently we are executing code from flash and we are using "GNU Tools ARM Embedded" compiler in GCC environment. Please help me in how to achieve this and what are the changes needed in the code.

[Hung Bui]

@Anand: Sorry that you have the case unanswered. I have my co-worker Håkon working on that case, please follow up :)