# Mac Stevens

Member Since: May 7, 2012

Country: United States

• I tried the formula from the datasheet “B3 = ((AC14+X3) [left shift] oss + 2) / 4 ”, which through operator precedence(http://en.wikipedia.org/wiki/Operators_in_C_and_C%2B%2B#Operator_precedence) is “B3 = ((AC14+X3) [left shift] (oss + 2)) / 4 ” , and it gave results that were very wrong. Using the formula here (http://mitat.tuu.fi/?p=78) which you have incorrectly copied in case 3, worked well for me.

I am now wondering if I use the datasheet formula with parantheses as you have would work.

• I tried the formula from the datasheet “B3 = ((AC1*4+X3)

• I tried your values. Actually, you omitted ac5, so I used 24862 (if I remember right). I got about the same values as using my own parameters.

Here are values from two of my sensors: // sensor 1 //m_ac1 = 7400; //m_ac2 = -1068; //m_ac3 = -14497; //m_ac4 = 33662; //m_ac5 = 24862; //m_ac6 = 21258; //m_b1 = 5498; //m_b2 = 55; //m_mb = -32768; //m_mc = -11075; //m_md = 2432;

// sensor 2 //m_ac1 = 8479; //m_ac2 = -1394; //m_ac3 = -14477; //m_ac4 = 33727; //m_ac5 = 25258; //m_ac6 = 22936; //m_b1 = 5498; //m_b2 = 78; //m_mb = -32768; //m_mc = -11075; //m_md = 2432;

• I used the formula from the datasheet and got pressures that were way off.

Btw, the datasheet formula is “B3 = ((AC1*4+X3)

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