What is fifo buffer and dmp packet size?can anybody plz explain this whole sectn

// MPU control/status vars
bool dmpReady = false; // set true if DMP init was successful
uint8_t mpuIntStatus; // holds actual interrupt status byte from MPU
uint8_t devStatus; // return status after each device operation (0 = success, !0 = error)
uint16_t packetSize; // expected DMP packet size (default is 42 bytes)
uint16_t fifoCount; // count of all bytes currently in FIFO
uint8_t fifoBuffer[64]; // FIFO storage buffer

// orientation/motion vars
Quaternion q; // [w, x, y, z] quaternion container
VectorFloat gravity; // [x, y, z] gravity vector
float ypr[3]; // [yaw, pitch, roll] yaw/pitch/roll container and gravity vector

  1. Tell us which sensor you have

  2. Tell us which library you are using

  3. Show all your code.

But I recognise the acronym "DMP". It stands for Digital Motion Processing and it's a term used in some IMU chips to describe how the chip does the sensor fusion between all the sensors inside the chip.

"FIFO" stands for First-In, First-Out. The Serial buffer is an example of a FIFO. When you type characters into Serial Monitor for the Arduino, you always want the first one you typed to be the first one the Arduino looks at.

The FIFO on many IMU chips will allow the chip to record data at high speed while the Arduino is busy doing something else. Then the Arduino can later download a bunch of readings in a single block. Because it's a FIFO, the readings retain the original order: first is first.

When OP posts the code - please post it properly within tags.