Hi
I’ve just purchased a Leonardo and plan to use it to drive programmable LEDs and I’m having a weird error.
I have a company called electric pedals that uses bicycles to power outdoor cinema. Because we use ultra capacitors and not batteries, it’s critical that during a performance that we are aware of the capacitor voltage. If people don’t pedal enough and the voltage falls to a low level, everything turns off. Traditionally we use small LED displays, but of course they are difficult to see from a distance.
So I plan to build a LED tower:
4x 1m strips of 60 addressable LEDs (pololu)
1x Arduino Leonardo
2x DCDC 12v to 5v Power supplies (15W)
I’m using pins:
a0: Vin (from external system)
gnd: Vo
12: LED controller
I’ve already written the code and tested (see below) it and it works perfectly.
This is the issue:
When I disconnect the computer and connect Arduino to an external power supply, it appears that the readings I’m getting from analogRead are nonsense.
Could it be some sort of GND issue?
Thanks
Colin
#include <PololuLedStrip.h>
int incomingByte = 0;
// Create an ledStrip object and specify the pin it will use.
PololuLedStrip<12> ledStrip;
// Create a buffer for holding the colors (3 bytes per color).
#define LED_COUNT 60
rgb_color colors[LED_COUNT];
int offset;
int delayvalue;
const float referenceVolts = 16; // the default reference on a 5-volt board
//const float referenceVolts = 3.3; // use this for a 3.3-volt board
const float R1 = 15000; // value for a maximum voltage of 10 volts
const float R2 = 6560;
// determine by voltage divider resistors, see text
const float resistorFactor = 1023.0 / (R2/(R1 + R2));
const int batteryPin = 0; // +V from battery is connected to analog pin 0
void setup()
{
Serial.begin(9600);
//turn LEDs off
for (int i = 0; i < LED_COUNT; i++)
{
colors[i] = (rgb_color){0, 0, 0};
}
ledStrip.write(colors, LED_COUNT);
}
void loop()
{
delayvalue = 1200;
int val = analogRead(batteryPin); // read the value from the sensor
float volts = (val / resistorFactor) * referenceVolts ; // calculate the rati
volts = ((referenceVolts/5)*volts); // print the value in volts
Serial.println(volts);
//turn off all LEDs
for (int j = 0; j < LED_COUNT; j++)
{
colors[j] = (rgb_color){0, 0, 0};
}
//bottom 10 red
for (int j = 0; j < 10; j++)
{
colors[j] = (rgb_color){255, 0, 0};
}
//top 10 green
for (int j = 50; j < LED_COUNT; j++)
{
colors[j] = (rgb_color){0, 255, 0};
}
//position based on voltage
if (volts < 13)
{
offset=11;
delayvalue = 100;
}
else if (volts >= 13 && volts < 13.05)
{
offset = 11;
delayvalue = 200;
}
else if (volts >= 13.05 && volts < 13.10)
{
offset = 12;
delayvalue = 300;
}
else if (volts >= 13.10 && volts < 13.15)
{
offset = 13;
delayvalue = 400;
}
else if (volts >= 13.15 && volts < 13.20)
{
offset = 13;
delayvalue = 500;
}
else if (volts >= 13.20 && volts < 13.25)
{
offset = 13;
delayvalue = 600;
}
else if (volts >= 13.25 && volts < 13.30)
{
offset = 14;
delayvalue = 700;
}
else if (volts >= 13.30 && volts < 13.35)
{
offset = 15;
delayvalue = 800;
}
else if (volts >= 13.35 && volts < 13.40)
{
offset = 16;
delayvalue = 900;
}
else if (volts >= 13.40 && volts < 13.45)
{
offset = 17;
delayvalue = 1000;
}
else if (volts >= 13.45 && volts < 13.50)
{
offset = 17;
delayvalue = 1100;
}
else if (volts >= 13.50 && volts < 13.55)
{
offset = 18;
delayvalue = 1200;
}
else if (volts >= 13.55 && volts < 13.60)
{
offset = 19;
}
else if (volts >= 13.60 && volts < 13.65)
{
offset = 20;
}
else if (volts >= 13.65 && volts < 13.70)
{
offset = 20;
}
else if (volts >= 13.70 && volts < 13.75)
{
offset = 21;
}
else if (volts >= 13.75 && volts < 13.80)
{
offset = 22;
}
else if (volts >= 13.80 && volts < 13.85)
{
offset = 23;
}
else if (volts >= 13.85 && volts < 13.90)
{
offset = 24;
}
else if (volts >= 13.90 && volts < 13.95)
{
offset = 24;
}
else if (volts >= 13.95 && volts < 14.00)
{
offset = 25;
}
else if (volts >= 14.00 && volts < 14.05)
{
offset = 26;
}
else if (volts >= 14.05 && volts < 14.10)
{
offset = 27;
}
else if (volts >= 14.10 && volts < 14.15)
{
offset = 28;
}
else if (volts >= 14.15 && volts < 14.20)
{
offset = 28;
}
else if (volts >= 14.20 && volts < 14.25)
{
offset = 29;
}
else if (volts >= 14.25 && volts < 14.30)
{
offset = 30;
}
else if (volts >= 14.30 && volts < 14.35)
{
offset = 31;
}
else if (volts >= 14.35 && volts < 14.40)
{
offset = 32;
}
else if (volts >= 14.40 && volts < 14.45)
{
offset = 32;
}
else if (volts >= 14.45 && volts < 14.50)
{
offset = 33;
}
else if (volts >= 14.50 && volts < 14.55)
{
offset = 34;
}
else if (volts >= 14.55 && volts < 14.60)
{
offset = 35;
}
else if (volts >= 14.60 && volts < 14.65)
{
offset = 35;
}
else if (volts >= 14.65 && volts < 14.70)
{
offset = 36;
}
else if (volts >= 14.70 && volts < 14.75)
{
offset = 37;
}
else if (volts >= 14.75 && volts < 14.8)
{
offset = 38;
}
else if (volts >= 14.80 && volts < 14.85)
{
offset = 39;
}
else if (volts >= 14.85 && volts < 14.90)
{
offset = 40;
}
else if (volts >= 14.90)
{
offset = 41;
}
else
{}
for (int j = offset-1; j < offset+9; j++)
{
colors[j] = (rgb_color){255, 255, 255};
}
ledStrip.write(colors, LED_COUNT);
//delay(delayvalue);
if (volts <= 13.5)
{
for (int j = 0; j < 10; j++)
{
//colors[j] = (rgb_color){0, 0, 0};
}
}
ledStrip.write(colors, LED_COUNT);
delay(delayvalue);
}
