Flowcode Support Board

Hi all!

Yes it´s me, who need help again, hope it´s ok

Using an Arduino Mega, ST7735 display and an ACS712.

To avoid flicker as much as possible in the display I only update when Amp is changing so I use " If new <> from old write the new and update Old"

It work fine in simulation , but in real world it update all time, without changing amp? Same issue with the ILI9341 display, but working fine with a
LCD display 4X20 serial. very stable.
I have try to use all kind of capacitors over the supply, ect.

Am I doing something wrong in my examble, or is there another way I can avoid or solve the problem or "flicker during update value", please.

Thank´s in advance

Jorgen

I would guess that the current reading is fluctuating enough to cause a refresh.

Maybe check if AmpOld and Amp differ by a certain 'threshold' amount and see if that helps?

Martin

Hi Martin!

Know I could count on you Thank you.

Already tested, no matter if I ground the ACS712 or use a battery, its always update, strange?

How quickly does the sensor refresh? - maybe add a delay in the loop. It will surely help - but maybe not in the right way (1s delay == 1s refresh)


Amp and oldAmp - are floats, cormparing them for equality might not work well..

Something like abs(oldAmp - amp) > 0.1might do the trick?

Would need to be fabs (#include <math.h>) or create your own (if(x < 0) return -x)

Martin

“Amp and oldAmp - are floats, cormparing them for equality might not work well..”
What i also thought, I try to change to byte 0-255 for test, same.

I Will test your suggest later today, you hear, Thank’s.

Br

Jorgen

I placed this in an calculationbox before compare

AmpOld = (AmpOld - Amp) > 0.1 rigth or ?

But still the same Neither the delay solve the issue.

Need to check if its negative as well (> -0.1 (hence the fabs - which would need to be in a C block)) - can you print out the readings? Do they look reasonable?

Martin

Hello MArtin!

Sorry take your time. When I remove the USB programming cable from the arduino it get much more stable

So this have some disturbtion on the reading. Thank you for your always helping.

Br Jorgen

Sounds like an interesting (and sensitive) sensor...

Good that you are getting some readings now.

Some displays are also very 'noisy' - I had issues with an SSD1306 - which introduced a huge amount of hum into a circuit.

Martin