Can I use the serial value from a processing app to change an analog PIN's value of arduino with Serial.read() & analoWrite() & connect that analog pin to another arduino's Same/Another Analog PIN. Then use the analogRead() in the 2nd arduino to read the value coming over that PIN & set position of a servo according to the value. Can it be done? I can use an ATtiny in that case to drive the servo separate. This way it won't have to be dependent on the RADAR-ARDUINO's timers. there's a reason I want to do that
On anything but a Due, "analogWrite" modifies the duty cycle of a digital signal, so an "analogRead" of such a signal will not return the value expected, without filtering.
And more over, it would be just helpful if you could help me with the problem I raised here. This way you would be saved of a lot of burden. I need to know about the filtering as you said up there & modifying it in my code will help me better understand .
Thank you
Well I tried with both the low pass filter way & the i2c way. low pass filter had some glitches. Sometimes it worked just fine. The system is not dependable for crucious moments. moving on to I2C.
The code for the arduino which will receive serail data from the Processing app is :
#include <Wire.h>
int data = 0;
void setup()
{
Serial.begin(9600);
Wire.begin();
}
void loop()
{
while(Serial.available() == 0)
{
int data = Serial.read() - '0';
Wire.beginTransmission(4);
Wire.write(data);
Wire.endTransmission();
Serial.flush();
}
delay(50);
}
& the code for the arduino that is connected to the previous arduino with I2C & a servo is
#include <Wire.h>
#include <Servo.h>
Servo myservo;
int x = 0;
void setup()
{
Wire.begin(4); // join i2c bus with address #4
Wire.onReceive(receiveEvent); // register event
//Serial.begin(9600);
myservo.attach(9);
}
void loop()
{
//delay(100);
myservo.write(x);
//Servoflush();
}
void receiveEvent(int howMany)
{
while( Wire.available() == 0) // loop through all but the last
{
x = Wire.read(); // receive byte as an intege
}
}
The problem is the servo keeps on moving . Never stops & is not affected by the serial data coming over the first arduino.
I guess there is some random data like the -49 for the subtraction (- '0') that we are employing in the first arduino program is causing the problem. My best guess. Any more problems sorted out & fixable is needed. help again.
\until & unless the data over I2C is 0, it'll keep on reading & set that value to a variable x. This variable is then used to define the position of a servo
dattasaurabh82:
\until & unless the data over I2C is 0, it'll keep on reading & set that value to a variable x. This variable is then used to define the position of a servo
I've modified the reciever arduino code a little. But not working still. Is it because there is something missing in the code or since I've not used Pull ups in tn the I2C bus? The servo keeps on rotating.
Does your servo work correctly if you just call servo.write() with a sequence of values to move it through a sequence of positions? You need to prove it's working correctly before you try to control it remotely.
Is your interrupt actually being called and receiving the value that was sent? Rather than write it directly to the servo, I suggest you write it to a volatile variable and then in loop read that and call servo.write to move the servo to that position - then you can use Serial.print statements to show what movements were received.
My servo's working fine(ran the "sweep" example with success). Also I tried to read the data coming to the 2nd arduino in the serial monitor (for my case COM-4) as I applied on the slider in applet running by processing, sending serial data to the first arduino(COM-14). I was communicating successfully.
Here are the codes :
------------Processing applet code--------------
import processing.serial.*;
import controlP5.*;
Serial port;
ControlP5 cp5;
int tilt = 0;
void setup()
{
size(200, 200);
port = new Serial(this, "COM4", 9600);
//port.bufferUntil('\n');
cp5 = new ControlP5(this);
cp5.addSlider("tilt")
.setPosition(88,7)
.setSize(20,180)
.setRange(0,180)
.setValue(90)
;
}
void draw()
{
background(0);
println(tilt);
port.write(tilt);
}
Arduino code which will receive serial data from the Processing & communicate with other arduino through I2C.
------------Arduino One Code-------------------
#include <Wire.h>
void setup()
{
Wire.begin();
Serial.begin(9600);
}
int x = 0;
void loop()
{
while(Serial.available())
{
x = Serial.read();
Wire.beginTransmission(4);
Wire.write(x);
Wire.endTransmission();
Serial.flush();
delay(20);
}
}
the code for Arduino which will receive data fro the 1st arduino & print the results in the serial monitor.
----------------Arduino Two Code--------------------
I guess the servo is getting same value multiple times & thus is freaking out(As it is coming serially all the time). I need to use something that will let the servo pick up a changed values once (as they change) only to make it move & not the same value continuously coming over serially to first arduino & to it through I2C finaly.
Something to flush the excess data.
Can any body test anything on this & help with a modified code please?
Isn't the Wire event handler called from an interrupt? If so you want to avoid doing Serial I/O in that - I suggest using a volatile variable to store the received value and put code in loop() to pass it on to the servo, and print the value out from there. Is Arduino 2 receiving the correct values?
