Hello, I'm working on a project where I have 7 Led's and want to turn each one on based on their angle (from -3 to +3) using a GY-521. I'm using a new library MPU6050_Light and using example GetAngle.ino, I'm having some trouble trying to get the LED to turn on, since I'm not sure how to set a specific angle for an individual LED using this library. I tired using an IF statement for pin 7 as a test but I'm not sure what to include for "if () < 3" between the parenthesis, I get an error "expected primary-expression after < " when verifying.
[code]
/* Get tilt angles on X and Y, and rotation angle on Z
* Angles are given in degrees
*
* License: MIT
*/
#include "Wire.h"
#include <MPU6050_light.h>
MPU6050 mpu(Wire);
unsigned long timer = 0;
//declaring pins
int Pin_1= 4;
int Pin_2= 5;
int Pin_3= 6;
int Pin_4= 7;
int Pin_5= 8;
int Pin_6= 9;
int Pin_7= 11;
void setup() {
Serial.begin(115200);
Wire.begin();
byte status = mpu.begin();
Serial.print(F("MPU6050 status: "));
Serial.println(status);
while(status!=0){ } // stop everything if could not connect to MPU6050
Serial.println(F("Calculating offsets, do not move MPU6050"));
delay(1000);
// mpu.upsideDownMounting = true; // uncomment this line if the MPU6050 is mounted upside-down
mpu.calcOffsets(); // gyro and accelero
Serial.println("Done!\n");
pinMode(Pin_1, OUTPUT);
pinMode(Pin_2, OUTPUT);
pinMode(Pin_3, OUTPUT);
pinMode(Pin_4, OUTPUT);
pinMode(Pin_5, OUTPUT);
pinMode(Pin_6, OUTPUT);
pinMode(Pin_7, OUTPUT);
}
void loop() {
mpu.update();
if((millis()-timer)>10){ // print data every 10ms
Serial.print("X : ");
Serial.print(mpu.getAngleX());
Serial.print("\tY : ");
Serial.print(mpu.getAngleY());
Serial.print("\tZ : ");
Serial.println(mpu.getAngleZ());
timer = millis();
}
if (mpu.getAngleY())<3
digitalWrite(Pin_7, HIGH);
}
[/code]
no problem, thank you that helped. Also, do you know if it would be possible to use a switch break case instead of using if statements for this part? How should I do it?
The "light" library seems okay, but they should have fixed my Issue by now.
The mpu.update() retrieves new data from the sensor. A update of 100Hz is normal for the MPU-6050 and you have already a millis-timer of 100Hz.
You could try to put the mpu.update() also in the millis-timer. The examples with the library don't do that, but it is worth a try.
I would do the updating of the leds also inside the millis-timer.
Could you get the angles and put them in variables ? That is a more common way to use a library.
You could put the pin numbers for the leds in a array. That makes the code easier.
Go through your sketch and make the text of the source code look nice, that is enough to fix the bug.
Does this look better ?
unsigned long previousMillis;
void loop()
{
// millis-timer of 100Hz
unsigned long currentMillis = millis();
// Get the sensor data every time the loop runs.
// Could this be also put the millis-timer ?
mpu.update();
// -----------------------------------------------
// A millis-timer of 100Hz
// -----------------------------------------------
if( currentMillis - previousMillis >= 10)
{
previousMillis = currentMillis;
// Get the data
float x = mpu.getAngleX();
float y = mpu.getAngleY();
float z = mpu.getAngleZ();
// set the leds
if( y < 3.0)
{
digitalWrite(Pin_7, HIGH);
}
// print the values
Serial.print( "X : ");
Serial.print( x);
Serial.print( "\tY : ");
Serial.print( y);
Serial.print( "\tZ : ");
Serial.print( z);
Serial.println();
}
}
Why? Are you trying to earn your switch/case merit badge or something?
Sometimes if/else is better, sometimes switch/case works better.
Often you can do it either way. There are many things that go into choosing which to employ in a given circumstance. This may be a case where switching (see what I did there?) would be more trouble than it's worth.
What is true is that sometimes one or the other may be more convenient to use.
If there are more than 2 cases that already resolve to an integer then I would favour switch/case every time. It is so much easier to read and understand than if/else if/else and the more cases there are the better it gets
I'm working on converting my code using a switch case but running into the same "expected primary expression before ','" on for (pin_7) statement, what could be wrong?
[code]
/* Get tilt angles on X and Y, and rotation angle on Z
* Angles are given in degrees
*
* License: MIT
*/
#include "Wire.h"
#include <MPU6050_light.h>
MPU6050 mpu(Wire);
unsigned long timer = 0;
void setup() {
Serial.begin(115200);
Wire.begin();
byte status = mpu.begin();
Serial.print(F("MPU6050 status: "));
Serial.println(status);
while(status!=0){ } // stop everything if could not connect to MPU6050
Serial.println(F("Calculating offsets, do not move MPU6050"));
delay(1000);
// mpu.upsideDownMounting = true; // uncomment this line if the MPU6050 is mounted upside-down
mpu.calcOffsets(); // gyro and accelero
Serial.println("Done!\n");
for (int pin_1 =4;,mpu.getAngleX()<3 )
pinMode(pin_1, OUTPUT);
for (int pin_2 =7;,mpu.getAngleX()<2)
pinMode(pin_2, OUTPUT);
for (int pin_3 =6;,mpu.getAngleX()<1)
pinMode(pin_3, OUTPUT);
for (int pin_4 =7;,mpu.getAngleX()<0)
pinMode(pin_4, OUTPUT);
for (int pin_5 =8;,mpu.getAngleX()<-1)
pinMode(pin_5, OUTPUT);
for (int pin_6 =9;,mpu.getAngleX()<-2)
pinMode(pin_6, OUTPUT);
for ((int pin_7 =11); (mpu.getAngleX()<-3);)
pinMode(pin_7, OUTPUT);
}
void loop() {
mpu.update();
if((millis()-timer)>10){ // print data every 10ms
Serial.print("X : ");
Serial.print(mpu.getAngleX());
Serial.print("\tY : ");
Serial.print(mpu.getAngleY());
Serial.print("\tZ : ");
Serial.println(mpu.getAngleZ());
timer = millis();
}
switch (mpu.getAngleX())
{
case 'a';
digitalWrite(Pin_1, HIGH);
break;
case 'b'
digitalWrite(Pin_2, HIGH);
break;
case 'c';
digitalWrite(Pin_3, HIGH);
break;
case 'd';
digitalWrite(Pin_4, HIGH);
break;
case 'e';
digitalWrite(Pin_5, HIGH);
break;
case 'f';
digitalWrite(Pin_6, HIGH);
break;
case 'g';
digitalWrite(Pin_7, HIGH);
break;
}
[/code]
for loops do not work better than goto. They work differently, may be easier to understand and to debug, but they do they "work better" ?
As you say, "Work better" is meaningless without context
Does it mean that less memory is used ?
Does it mean that the code works faster ?
Both ?
Something else ?
Does it actually matter as long as the sketch works well enough to meet the requirements ?
Compared to C++ English is a terrible language, being so open to interpretation. What we need is the equivalent of K&R's " The C Programming Language" for English and that is before we introduce the idea of British English and American English into the discussion !
