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Time interval for superchart data for 1 second interval?

hi, Can blynk collect accelerometer data for every 1 second interval? i want to obtain 3 data of accelerometer (x,y,z) using nodemcu from MPU6050 sensor. it will be logged into superchart widget before export to csv file. But unfortunately it only collect data for 1 minute interval. I want to collect data for 1 second interval. how can i do that with nodemcu and suprchart widget? please help

No.

Data is buffered over a one minute period then averaged and the average written to the database, so one minute granularity is the best you can get.

Superchart supports currently 2 types of granularity:

  • Minute granularity - 1h , 6h , 1d ;
  • Hour granularity - 1w , 1m , 3m ;

This means that minimum chart update interval is 1 minute for 1h , 6h , 1d periods. 1 hour for 1w , 1m and 3m periods. As Blynk Cloud is free to use we have a limit on how many data you can store. At the moment Blynk Cloud accepts 1 message per minute per pin. In case you send your data more frequently your values will be averaged. For example, in case you send value 10 at 12:12:05 and than again 12 at 12:12:45 as result in chart you’ll see value 11 for 12:12.

You could try Adafruit IO Plus at around $100 per year, which allows 1 second granularity, or you could set-up a device such as a Raspberry Pi with some additional attached storage and write the data to a database, probably via MQTT and Node-Red.

Pete,

thanks for the explanation. I will try MQTT with nodemcu. (if available). thx again

You can certainly use a NodeMCU to send data via MQTT, that’s how all of my home automation projects work.
You’ll need a Pi or similar, or a Windows machine that’s on 24/7 with no sleep enabled, as your MQTT/Node-Red server and to run your database on.

Pete.