›

How to know when logger has completed logging data??

KamranKamran
edited September 2016 in iOS
I have connected Metawear C to an iOS device and from device I start logging data of accelerometer at 10Hz. Following are my queries :-

1) If Metawear can log 14000 entries maximum, at 10Hz the device will log data for 20-25 mins ? 
2) When i could exactly know that logger has finished logging on its own or when 14000 entries are completed ??
3) Once 14000 entries are logged how to clear those logs ??

Thanks,
Kamran Ahmed

Comments

  • EricEric
    1. Accelerometer takes 2 entries per data so only about 10 min.
    2. You can add a timer to your app to connect and download at the appropriate time based on your logging frequency.
    3. Logs are cleared when they are downloaded
  • KamranKamran
    "1. Accelerometer takes 2 entries per data so only about 10 min."

    How will i achieve 14000 entries then ? 

    Yet I was only able to log 3900 entries in 6 mins. How will i utilize maximum entries and time ?
  • EricEric
    You can't as mentioned in my previous post that acceleration data requires 2 entries.

    Where are you getting this 14000 number from?  The firmware for the new MetaWear C boards is larger than the other builds which does cut into the amount of flash memory available.
  • KamranKamran
    Hey Eric, 

    Thanks for quick response. I have read about 14000 entries for this link in logging section. 

    Oh okay, so in short if i have some activity to monitor human posture for 30 minutes I will have to log values for 5 minutes then download them and then again start logging?
  • EricEric
    You can simply stream the data if you aren't running the sensors that quickly.
  • KamranKamran
    Yes i could stream data but issue is i want to connect multiple metawears. They could be on arm and leg. So streaming both simoultaniously wont be good idea thats why wanted to log data.
  • EricEric
    Unfortunately you are limited in your options then.  The current boards do not have that much on board flash memory to hold a large quantity of accelerometer/gyro data so you either need to get a MetaMotion board, which comes with an external flash chip, or get a few more host devices to handle the stream.  
This discussion has been closed.