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Super Chart showing incorrect data

Hi,

I need help with historical data on a superchart. I have two sensors updating code to blynk. I can view the live data but not the historical. When I change it to historical, it gives me a trend that shows much different numbers. See the trend, it should be around 650psi or so and its showing ±50 on the trend with no data.


See code below

 pressureValue = analogRead(pressureInput);
  pressureValue = ((pressureValue - pressureZero) * pressuretransducermaxPSI) / (pressureMax - pressureZero);

  Blynk.virtualWrite(V5, pressureValue, 1);

  pressureValue1 = analogRead(pressureInput1);
  pressureValue1 = ((pressureValue1 - pressureZero1) * pressuretransducermaxPSI1) / (pressureMax1 - pressureZero1);

  Blynk.virtualWrite(V6, pressureValue1, 1);

I assume that what you are trying to do here is to tell Blynk that you want the pressureValue variable to be sent to Blynk with one decimal place resolution, hence the ,1 in your virtualWrite copmmand?

That isn’t how the virtualWrite command works, and what you are actually doing is sending an array of values to the virtual pin.

You should remove the ,1 from your virtualWrite command.

You should also be aware that Blynk Legacy stores all the values sent to a virtual pin over a 1 minute period, then averages them before writing them to the database. It’s these stored averaged values that are displayed in SuperChart in the 15min to 1 day views.

Pete.