Re: NM Galileo project - Computer controlled watering system

I made some progress this weekend. My Jameco order came in so I go out my breadboards and went crazy.

I seem to be able to read all the voltages so far, but I haven't tried to turn on or off the transistors.

I measured the voltage out of the solar panel and read it into the Galialeo, I can also read the

battery voltage. I needed more MS Excel experience so I figured out how to calculate the line

using Excel. It was pretty easy but I hadn't done it before so it was good experience.

Here's the spreadsheet/line equation for my solar voltage. I needed that to display the

voltage in the Arduino serial window. I tested by moving my desk lamp closer to or farther from the

panel.

I still need to check the current drain of the Galileo and also see if I can turn on and
off the voltage at the battery. Here's the circuit so far (with the code used to read/print voltages).

/* Solar cell battery charger/regulator
All this does is read the voltage at solar cell (A0) and
The battery voltage (A1). It blinks the LED to show that
it's looping - in case the serial didn't work ;-)
*/
#define voltage_in 0
#define voltage_out 1
#define charge_enable 11

int x;
int y;
// Pin 13 has an LED connected on most Arduino boards.
// give it a name:
int led = 13;

int chon = 5000; // charge on time
int choff = 2000; // charge off time

void setup() {
    Serial.begin(9600); // opens serial port, sets data rate to 9600 bps
    // initialize the digital pin as an output.
    pinMode(led, OUTPUT);
    //digitalWrite(charge_enable, LOW);
}

void loop()   {
  digitalWrite(led, HIGH);   // turn the LED on (HIGH is the voltage level)
  //delay(1000);               // wait for a second
  x = analogRead(voltage_in); // voltage from solar panel
  y = analogRead(voltage_out); // voltage on battery

  Serial.print("Solar A/D count is: ");
  Serial.print(x);
  Serial.print(". Which is about this many volts: ");
  Serial.println((x * .0579) + .6249);

  Serial.print("Battery A/D is: ");
  Serial.print(y);
  Serial.print(". Which is about this many volts: ");
  Serial.println((y * .0579) + .6249);

  delay(1000);
  digitalWrite(led, LOW);    // turn the LED off by making the voltage LOW
  delay(1000);
}