Hello everyone
The problem is: I need to read voltages across a segment of a polymer display.
Some info about segment: There are two electrodes counter electrode (CE) and pixel electrode (PE). To change color from white to blue, need to apply 2-3 volts on counter electrode (CE) and 0 v on PE for enough time. similarly in order to make segment from blue to white need to apply 2-3 volts on PE and 0 v on CE. But by supplying these voltages some charge get developed across the segment and if you remove the battery and measure the voltages across the segment it shows 1.2 V for blue color and -1.9 v for white color. For measuring 1.2 v I am using an analog port which is connected at the same point where CE is connected to digital port 3. I implemented this by supplying 2.5 volts through a voltage divider as shown in attached figure. By making the digital port 3 as input it means it will no more supply any voltages to the segment and meanwhile I am measuring 1.2 v and printing on serial monitor. But the problem is it does not show 1.2 v but 0.13 v instead. Can anyone help with that?
I have arduino mega2560.
int PEA = A8;
int PE = 2; // PE:Pixel electrode of segment
int CE = 3; // CE: counter electrode of segment
int temp_val_PE = 0;
float val_PE;
void setup()
{
Serial.begin(9600);
pinMode(PE,OUTPUT);
pinMode(CE,OUTPUT);
Serial.println("PE Val");
}
void loop()
{
analogWrite(CE,0); // for white color
analogWrite(PE,255);
delay(1000);
analogWrite(CE,255); //for blue color
analogWrite(PE,0);
delay(3000);
pinMode(CE,INPUT);
pinMode(PE,INPUT);
temp_val_PE = analogRead(A8);
val_PE = temp_val_PE * (5.0 / 1023.0);
Serial.println("");
Serial.println(val_PE);
delay(10);
}
Thanks for reading the problem.
