Why "fifoBuffer" values of indexes 2,3,6,7,10,11 are not passed in the teapotPacket[] array?

Question

I'm using the MPU6050 library by Jeff Rowberg. In the code, while passing data to the Teapot library(for processing,i.e, graphics emulation), whole fifobuffer is not passed. Why is that so ?

Here's the code, see only few indices of fifobuffer array are passed.

teapotPacket[2] = fifoBuffer[0];
teapotPacket[3] = fifoBuffer[1];
teapotPacket[4] = fifoBuffer[4];
teapotPacket[5] = fifoBuffer[5];
teapotPacket[6] = fifoBuffer[8];
teapotPacket[7] = fifoBuffer[9];
teapotPacket[8] = fifoBuffer[12];
teapotPacket[9] = fifoBuffer[13];

Further, also clarify one more thing,

uint8_t teapotPacket[14] = { '$', 0x02, 0,0, 0,0, 0,0, 0,0, 0x00, 0x00, '\r', '\n' };

Why the teapotPacket[14] array is initialised with these weird hex numbers ?

Here's the full code, just in case you want to look at -https://codeshare.io/2j0RkK — Rohit Lal, Feb 17 '17 at 16:13
That depends on what `InvenSense Teapot demo format` is. I could not find any documentation about that: contact the developer. — Patrick Trentin, Feb 19 '17 at 10:24

score 0 · Accepted Answer · answered Mar 29 '19 at 14:14

In the code, while passing data to the Teapot library(for processing,i.e, graphics emulation), whole fifobuffer is not passed. Why is that so ?

Digging deeper into the library code, I found out that its just a "InvenSense Teapot demo" format for displaying the quaternion values.

Why the teapotPacket[14] array is initialised with these weird hex numbers ?

Its a packet structure format for InvenSense teapot, used for storing the sensor readings like quaternion values.

A little more information about : "Quaternion values" :

Quaternions is a number system that extends the complex numbers used for calculations involving three-dimensional rotations such as in three-dimensional computer graphics, computer vision, and crystallographic texture analysis.

Why "fifoBuffer" values of indexes 2,3,6,7,10,11 are not passed in the teapotPacket[] array?

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