Synchronization of local time between two LoPy's

[assia]

Hello

I want to have the same local time in nanoseconds for both lopys, I use at the moment time.time () * math.pow (10,9) but this returns the nanoseconds since the power up of lopys so i try to put them power up at the same time but there is a time lag.

Do you have any solution to synchronize the local time of two lopys using RTC for example?

@LoPy-2016-Kickstarter-Backers @LoPy-Beta-Summer-2016

[Majdoulina makbal]

Hi assia, did you solve the problem ?

[livius]

@assia said in Synchronization of local time between two LoPy's:

What is the problem knowing that my computer is connected to the Internet when i do it ?

Do you mean Lopy not computer right?
If your Lopy is connected to the router (STA or AP_STA mode)
then you can synchronise time by calling:

rtc.ntp_sync("pool.ntp.org")

[assia]

Hi @livius when i try to synchronize with the ntp server and i try to get the actual time using:

rtc.now()

i get :

(1970, 1, 1, 0, 9, 11, 833500, None)

but I want to have the current time like the year 2017 for example.
What is the problem knowing that my computer is connected to the Internet when i do it ?

thanks

[livius]

@assia
if you do not use deepsleep (reset)
then you can do this only once

but this still is not nanosecond ;-)

[assia]

@livius thanks for your response

if i use rtc.ntp_sync("pool.ntp.org") should the lopy's be connoted to the internet all the time or just at the time of synchronization?

[livius]

@assia said in Synchronization of local time between two LoPy's:

Do you have any solution to synchronize the local time of two lopys using RTC for example

rtc.ntp_sync("pool.ntp.org")

but do you really mean nanoseconds ?
What do you try to accomplish that you should have nanosecond precision - especially synchronized between two devices

• i suppose that also RTC is here not accurate.

you can use

utime.ticks_cpu()
 resolution (25 ns).