Hello everyone,
I am currently working on a rather simple project which includes a RGB LED which is supposed to fade at certain coordinates coming from a GPS module.
Although I'm not a routined programmer I managed to collect and merge two codes for reading the GPS data and fading the LED.
The only issue I have now (as far as I can tell) is that the delay in the fade code is interrupting the GPS data input. I read many threads concerning the same issue and methods regarding multithreading such as blinking led without delay but I just cannot get my head around how to implement the millis() function instead of the delay in this case.
This is the part of the code with the delay
void crossFade(int color[3]) {
// Convert to 0-255
int R = (color[0] * 255) / 100;
int G = (color[1] * 255) / 100;
int B = (color[2] * 255) / 100;
int stepR = calculateStep(prevR, R);
int stepG = calculateStep(prevG, G);
int stepB = calculateStep(prevB, B);
for (int i = 0; i <= 1020; i++) {
redVal = calculateVal(stepR, redVal, i);
grnVal = calculateVal(stepG, grnVal, i);
bluVal = calculateVal(stepB, bluVal, i);
analogWrite(redPin, redVal); // Write current values to LED pins
analogWrite(grnPin, grnVal);
analogWrite(bluPin, bluVal);
delay(wait); // Pause for 'wait' milliseconds before resuming the loop
}
It would be amazing if you could help me with this last step to (hopefully) solving my problem.
Here's the full code:
#include <SoftwareSerial.h>
#include <TinyGPS.h>
long lat,lon; // create variable for latitude and longitude object
long lat2,lon2; // copy of lat lon
// Output RGB LED
int redPin = 9; // Red LED, connected to digital pin 9
int grnPin = 10; // Green LED, connected to digital pin 10
int bluPin = 11; // Blue LED, connected to digital pin 11
// Color arrays
int black[3] = { 0, 0, 0 };
int dimPurple[3] = { 20, 0, 30 };
// Set initial color
int redVal = black[0];
int grnVal = black[1];
int bluVal = black[2];
int wait = 3; // 10ms internal crossFade delay; increase for slower fades
int hold = 0; // Optional hold when a color is complete, before the next crossFade
int repeat = 0; // How many times should we loop before stopping? (0 for no stop)
// Initialize color variables
int prevR = redVal;
int prevG = grnVal;
int prevB = bluVal;
SoftwareSerial gpsSerial(2,3); //create sensor connection
TinyGPS gps; // create GPS Object
void setup() {
pinMode(redPin, OUTPUT); // sets the pins as output
pinMode(grnPin, OUTPUT);
pinMode(bluPin, OUTPUT);
lat2=lat; // copy variables
lon2=lon;
Serial.begin(9600); // connect serial
gpsSerial.begin(9600); // connect gps sensor
}
void loop() {
while(gpsSerial.available()){ // check for gps data
if(gps.encode(gpsSerial.read())){ // encode gps data
gps.get_position(&lat,&lon); // get latitude and longitude
// serial display position
Serial.println("Position: ");
Serial.print("lat ");Serial.print(lat);Serial.print(" lon ");Serial.println(lon);
}
}
if( (lat <= 51456200 && lat2 >= 51456000) && (lon <= 5468950 && lon2 >= 5468600) ){
crossFade (black);
crossFade (dimPurple);
}
}
/* BELOW THIS LINE IS THE MATH -- YOU SHOULDN'T NEED TO CHANGE THIS FOR THE BASICS
*
* The program works like this:
* Imagine a crossfade that moves the red LED from 0-10,
* the green from 0-5, and the blue from 10 to 7, in
* ten steps.
* We'd want to count the 10 steps and increase or
* decrease color values in evenly stepped increments.
* Imagine a + indicates raising a value by 1, and a -
* equals lowering it. Our 10 step fade would look like:
*
* 1 2 3 4 5 6 7 8 9 10
* R + + + + + + + + + +
* G + + + + +
* B - - -
*
* The red rises from 0 to 10 in ten steps, the green from
* 0-5 in 5 steps, and the blue falls from 10 to 7 in three steps.
*
* In the real program, the color percentages are converted to
* 0-255 values, and there are 1020 steps (255*4).
*
* To figure out how big a step there should be between one up- or
* down-tick of one of the LED values, we call calculateStep(),
* which calculates the absolute gap between the start and end values,
* and then divides that gap by 1020 to determine the size of the step
* between adjustments in the value.
*/
int calculateStep(int prevValue, int endValue) {
int step = endValue - prevValue; // What's the overall gap?
if (step) { // If its non-zero,
step = 1020/step; // divide by 1020
}
return step;
}
/* The next function is calculateVal. When the loop value, i,
* reaches the step size appropriate for one of the
* colors, it increases or decreases the value of that color by 1.
* (R, G, and B are each calculated separately.)
*/
int calculateVal(int step, int val, int i) {
if ((step) && i % step == 0) { // If step is non-zero and its time to change a value,
if (step > 0) { // increment the value if step is positive...
val += 1;
}
else if (step < 0) { // ...or decrement it if step is negative
val -= 1;
}
}
// Defensive driving: make sure val stays in the range 0-255
if (val > 255) {
val = 255;
}
else if (val < 0) {
val = 0;
}
return val;
}
/* crossFade() converts the percentage colors to a
* 0-255 range, then loops 1020 times, checking to see if
* the value needs to be updated each time, then writing
* the color values to the correct pins.
*/
void crossFade(int color[3]) {
// Convert to 0-255
int R = (color[0] * 255) / 100;
int G = (color[1] * 255) / 100;
int B = (color[2] * 255) / 100;
int stepR = calculateStep(prevR, R);
int stepG = calculateStep(prevG, G);
int stepB = calculateStep(prevB, B);
for (int i = 0; i <= 1020; i++) {
redVal = calculateVal(stepR, redVal, i);
grnVal = calculateVal(stepG, grnVal, i);
bluVal = calculateVal(stepB, bluVal, i);
analogWrite(redPin, redVal); // Write current values to LED pins
analogWrite(grnPin, grnVal);
analogWrite(bluPin, bluVal);
delay(wait); // Pause for 'wait' milliseconds before resuming the loop
}
// Update current values for next loop
prevR = redVal;
prevG = grnVal;
prevB = bluVal;
delay(hold);
}
Thanks a lot