Wire.endTransmission and Timer no function

Using Arduino Programming Questions
1

Hello,

For a project I am trying to read data from a Bosch BNO055 with the I2C connection every 20 ms. For reading data at the correct frequency I am using a timer (I tried MsTimer2, TimerOne, TimerThree, milis() and elapsedMilis). However everytime I call the function Wire.endTransmission for the I2C connection, the program seems to stop.
Does somebody know why this happens? And/or does know a solution to this problem?
Thanks!

Cheers,
Vivian

2

Does somebody know why this happens?

There is something wrong with your code.

And/or does know a solution to this problem?

Fix your code.

3

There is nothing wrong with my code, for in this simple code it doesn't work either.
Tell me where I made a mistake in this code.

#include <Wire.h>
#include <MsTimer2.h>

#define BNO055 0x29
#define EUL_DATA_X_LSB 0x1A
void setup() {
Serial.begin(9600);
MsTimer2::set(100,startLoop);
MsTimer2::start();
}

void loop() {
}

void startLoop(){
Wire.beginTransmission(BNO055); // Could also be left out, no difference.
Wire.write(EUL_DATA_X_LSB); // Could also be left out, no difference.
Wire.endTransmission(); // If this line is commentated out, it works fine.
Serial.println("Hello");
}

4

It looks to me that you might be calling something that requires interrupts to be enabled, inside an ISR.

So yes, there is something wrong with your code.

5

Also you haven't read the "sticky" about using code tags, so there is also something wrong with the way you posted your code.

6

Vivian_anoek:
There is nothing wrong with my code, for in this simple code it doesn't work either.

If the error is not in your code, where is it?

7

It looks to me that you might be calling something that requires interrupts to be enabled, inside an ISR.

Like Serial.print().

Wire.beginTransmission(BNO055);    // Could also be left out, no difference.

Perhaps you ought to pay some attention to what these functions ACTUALLY do. This sets up a buffer to hold some data. Of course not doing that won't cause the ISR problems.

Wire.write(EUL_DATA_X_LSB);         // Could also be left out, no difference.

Put some data in the buffer. Of course not doing that won't cause the ISR problems.

  Wire.endTransmission();                 // If this line is commentated out, it works fine.

Actually communicate with the device, sending the data in the buffer. If you don't do that, and you don't have a problem, then just stop doing it.

If you stop doing it, and you have a problem, then you need to stop pissing and moaning and figure out why the Arduino can't talk to the device!