[Ovmsdev] timestamps on push notifications and logs

Nikolay Shishkov nshishkov at yahoo.com
Mon Jun 16 22:16:14 HKT 2014

Thanks Mark, 
Isn't it too complicated to fetch the time from the GSM modem? 
How about changing the following 2 lines in the net.c code:
        if( b = strtokpgmram( net_buf+2, "," ) )
            ; // Time

To something like this
        if( b = strtokpgmram( net_buf+2, "," ) )
            gps_time_str = *b; // Time
            gps_time_acquired = car_time; // when was that time acquired

Then we can discuss if car_time should be the same as gps_time (probably not), or if gps_time could be used for logging and other selected functions? Or even if we can have a get_time() function (what would be a good location) that would encapsulate the time getting process and do some simple magic - say something like this:

        long get_time() {
if (gps_time_acquired != 0)
return gps_time_long + (car_time - gps_time_acquired); = *b; 
return car_time;

Any issues with such approach? Apart from GPS antenna not connected to the board?


Here: unsigned long car_time Time (in seconds), as measured by the car. The 0 value of this can be whatever the car module desires.
It is acceptable to merely initialize this to zero and increment it by 1 for every ticker1() received.
Alternatively, a more accurate method is to read the real time clock from the vehicle CAN bus (if available) and update from there.  I think the Tesla Roadster is the only vehicle actually updating it from the CAN bus. There was some (fairly recent) discussion about getting this from the GPS, and Tom did the foundation work (utils.{h,c} JDEpoch, JdToYMD, JdFromYMD, and datestring_to_timestamp  in net.c), but we haven't completed the changes to the core net.c (+CCLK handler) to do this yet. I attach the mailing list eMail showing how this will be done. Regards, Mark. On 15 Jun, 2014, at 9:35 pm, Nikolay Shishkov <nshishkov at yahoo.com> wrote: >Hi, >>I am getting strange time on my push notifications and on the logs. >Looking at the code it seem a variable called car_time is used to produce string indicating time. >Also looking at the code I can not seem to find where this car_time variable is set. The only place I could find is the
 vehicle_teslaroadster.c . >>If I am not missing something wouldn't it be beneficial to get the time from the GPS or the GSM network instead? >>I am attaching a screenshot of my app where the timestamp of the push notification is visible together with the time displayed on my phone. >>Nikolay
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