Hey Guys,
I'm trying to understand the output of BMP180 - I2C
In the Datasheet I found this Formular:
What exactly is meant with this formular.
UT= MSB << 8 + LSB
MSB is 0xf6 - this can be found on my output of the logic analyzer.. but where is LSB and how what is <<?
Can some give me a quick overview how I can comprehand this? MY goal is to calculate the Temperature with the formular in the datasheet in combination from the logic analyzer data.
Greetings
Most Significant Byte
Least Significant Byte.
<< is the logical left shift operator.
UT is assigned the sum of the MSB shifted left 8 places and added to LSB.
That code is most often used when two 8 bit bytes are read (for example from an I2C device). Those two bytes are called LSB (Least significant byte) and MSB (most significant byte). Eachbyte contains half of a 16 bit integer value.
Assuming thaz MSB was binary 0000001 and LSB was binary 00000011.
MSB << 8 would get 0000000100000000, adding in LSB would get a final result of 0000000100000011 which is a 16 bit integer with the value of 256 (from MSB) plus 3 (from LSB) equalling 259.
MSB LSB is a 16 bit binary number sent in two separate operations of 8 bits each
MSB LSB
01001010 10010100
<< is shift a binary number to the left. Being binary each time you shift you essentially multiply by 2 ( for decimal consider 10<<2 = 1000 ) so shifting by 8 is the same a multiplying by 256.
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