for my project for school that decides if I pass this year or not I have to work with an MPU-6050 and an Arduino Due. The MPU works via I2C and ive got that part working. I can get values and its linked. But there is one problem, with my code it seems that I am not getting the right values! Or that I am processing them wrongly. I will show you the Arduino C code and my code and maybe someone knows what I am doing wrong.
Here is the arduino code with output:
#include<Wire.h>
const int MPU_addr=0x68; // I2C address of the MPU-6050
int16_t AcX,AcY,AcZ,Tmp,GyX,GyY,GyZ;
void setup(){
Wire.begin();
Wire.beginTransmission(MPU_addr);
Wire.write(0x6B); // PWR_MGMT_1 register
Wire.write(0); // set to zero (wakes up the MPU-6050)
Wire.endTransmission(true);
Serial.begin(9600);
}
void loop(){
Wire.beginTransmission(MPU_addr);
Wire.write(0x3B); // starting with register 0x3B (ACCEL_XOUT_H)
Wire.endTransmission(false);
Wire.requestFrom(MPU_addr,14,true); // request a total of 14 registers
AcX=Wire.read()<<8|Wire.read(); // 0x3B (ACCEL_XOUT_H) & 0x3C (ACCEL_XOUT_L)
AcY=Wire.read()<<8|Wire.read(); // 0x3D (ACCEL_YOUT_H) & 0x3E (ACCEL_YOUT_L)
AcZ=Wire.read()<<8|Wire.read(); // 0x3F (ACCEL_ZOUT_H) & 0x40 (ACCEL_ZOUT_L)
Tmp=Wire.read()<<8|Wire.read(); // 0x41 (TEMP_OUT_H) & 0x42 (TEMP_OUT_L)
GyX=Wire.read()<<8|Wire.read(); // 0x43 (GYRO_XOUT_H) & 0x44 (GYRO_XOUT_L)
GyY=Wire.read()<<8|Wire.read(); // 0x45 (GYRO_YOUT_H) & 0x46 (GYRO_YOUT_L)
GyZ=Wire.read()<<8|Wire.read(); // 0x47 (GYRO_ZOUT_H) & 0x48 (GYRO_ZOUT_L)
Serial.print(" | GyY = "); Serial.print(GyY);
Serial.print("\n");
//Serial.print(" | GyZ = "); Serial.println(GyZ);
delay(100);
}
With output:
| AcX = 16676
| AcX = 16628
| AcX = 16740
| AcX = 16692
| AcX = 16660
| AcX = 16676
| AcX = 16780
| AcX = 16684
| AcX = 16612
| AcX = 16644
| AcX = 16588
Now this seems to be fine. But my c++ code is not working properly at all it seems. Here it is:
#include "hwlib.hpp"
#include <iomanip>
int main( void ){
// kill the watchdog
WDT->WDT_MR = WDT_MR_WDDIS;
namespace target = hwlib::target;
// int16_t zaxis, yaxis;
byte adress = 0x68;
auto scl = target::pin_oc{ target::pins::scl };
auto sda = target::pin_oc{ target::pins::sda };
auto i2c_bus = hwlib::i2c_bus_bit_banged_scl_sda{ scl,sda };
for(;;){
byte data[8] = {0x3B};
i2c_bus.write(adress, data, 1);
i2c_bus.read(adress, data, 8);
hwlib::cout << (int16_t)data[0] << (int16_t)data[1] << (int16_t)data[2]<< (int16_t)data[3] << (int16_t)data[4] << (int16_t)data[5] << (int16_t)data[6] << (int16_t)data[7] << "\n";
hwlib::wait_ms(500);
}
}
To the people wondering what hwlib is, its a library provided by school. So you see the read and write methods of hwlib and if you are wondering how they look:
void write( fast_byte a, const byte data[], fast_byte n ) override {
write_start();
write_byte( a << 1 );
for( fast_byte i = 0; i < n; i++ ){
read_ack();
write_byte( data[ i ] );
}
read_ack();
write_stop();
}
//
void read( fast_byte a, byte data[], fast_byte n ) override {
write_start();
write_byte( ( a << 1 ) | 0x01 );
read_ack();
for( fast_byte i = 0; i < n; i++ ){
if( i > 0 ){
write_ack();
}
data[ i ] = read_byte();
}
write_stop();
}
Now, it seems that it writes the data to the byte array that I send with the function. And with that i get the data and put it on the screen with hwlib::cout. It works just like the normal std::cout but the teacher said to use it.
Output:
651601120216235240
65522552160248235192
65200120184235240
642280321100235240
64244010812423616
650255208132235224
654004018235224
641320280208235224
654255236102360
65480480200235224
I will continue trying to figure it out because I can not fail this project haha, but if someone has an answer and they can tell me what im doing wrong and how I should be doing it that would make my year, litterally.
Thankyou in advance!
The values are 2 byte long, but you output one byte at a time. This only works for hex, but not for decimals.
Note that 16640=0x4100, and 0x41=65, so (at least) the first two digits of each line are correct.