TM4C123G: Need to validates the output result of MPU9150 sensor (QS-Logger o/p)

Pls. reply on above said post..........

Hello Pramod,

Did you check if there are calibrated devices in the market which can be used to compare or benchmark the same

Regards

Amit

Dear Amit,

Could you pls. suggest me one of them?

Regards,

Pramod

Hello Pramod,

Sorry, Can't help you there.

Regards

Amit

Dear Amit,

I want to verify the output of QS-Logger (MPU 9150, 9 Axis). So TI can provide us any guideline or document which will hep us to improve our base knowledge.

Your kind help is highly appreciated!

Regards,

Pramod

Hello Pramod,

If it about the MPU9150 that you want info on, then it is best seen at the vendor for MPU9150 documentation.

Regards

Amit

Amit,

Did you seen the o/p of MPU9150 on Tiva Dev. board TM4C123G? if yes then the o/p of this sensor which is displayed on OLED, can we use this o/p for a reference of our measurement unit?

and if "NO" then I would like to request your support, pls. get the information of QS-logger in depth like a application note.

Regards,

Pramod

Hello Pramod,

The Interface between the MPU9150 and TIVA is I2C, so seeing the output all the time is "not" possible. How do you propose to use the o/p on I2C as a reference for measurement unit?

Regards

Amit

That much of sense we have. Thanks

Kindly find the below conversions steps of Accel from QS logger:

1. // Get floating point version of angular velocities in rad/sec
                    MPU9150DataGyroGetFloat(&g_sMPU9150Inst, &g_pfGyro[X], &g_pfGyro[Y], &g_pfGyro[Z]);

2.   Conversion

                    g_i16Accel[0]= (int16_t) ((g_pfAccel[0] /9.81f)*100.f);
                    g_i16Accel[1]= (int16_t) ((g_pfAccel[1] /9.81f)*100.f);
                    g_i16Accel[2]= (int16_t) ((g_pfAccel[2] /9.81f)*100.f);

3. Print result on consol

            for(int i = 0; i <= 2;i++)
                    {
                        static char pcViewerBuf1[24];
                    
                        int16_t i16Accel = g_i16Accel[i];
                        i16Accel *= (i16Accel < 0) ? -1 : 1;
                        usnprintf(pcViewerBuf1, sizeof(pcViewerBuf1), "%c: %c%d.%02u g\t",
                                         i+'X',    g_i16Accel[i] < 0 ? '-' : '+',
                                         i16Accel / 100, i16Accel % 100);
                        
                        UARTprintf(pcViewerBuf1);
                        ROM_SysCtlDelay(100000);

                    }

My question is very simple, we want a reference, which TI was used for their QS logger code. If this conversion is at actual of its physical measurements, then can we used Tiva TM4C123G dev. board as a measuring device which helps to get the measurements readouts.

pls. reply

Hello Pramod

Checking this internally. I would come back with some question (in case clarification is required) and post a response.

Regards

Amit

Hello Pramod,

There is no real calibration done for the MPU9150 device. There could be some errors due to soldering and device mount. One of the methods to calibrate the system is to use a standard horizontal level and mount the board to get the offset error and calibrate the same.

Regards

Amit

Amit,

On above said clarification is valid for mounting and soldering the chip on board, did you not understand what I mean,once again I repeat the que.,we want a reference measurement  i/p for  Accel, Gyro & e-composs, we found the same in TI code example like QS logger, If we run this program on Dev. Board its start to shows the current reading on display. Just like a Digital multimeter(for measurement of any electrical quantity). So can we used Tiva TM4C123G dev. board with function of QS-logger as a measuring device for Accel, Gyro and e-composs measurement readouts.

Regards,

Pramod

Hello Pramod,

Yes, with the certain degree of %error.

Regards

Amit

Thanks Amit,