Figure 5. SPI Start Conversion Datagram
Command to Start Pressure and Temperature Conversion, 0x24
Figure 6. SPI Read Results Datagram
Pressure MSB
Pressure LSB
= 0x67
= 0xC0 Pressure
Temperature MSB = 0x80
Temperature LSB = 0x40 Temperature
= 0x67C0 = 0110 0111 11 00 0000
= 415 ADC counts
= 0x8040 = 1000 0000 01 00 0000
= 513 ADC counts
3.7 Example of Pressure Compensated Calculation in Floating-point Notation
a0 coefficient = 2107.875
b1 coefficient = -2.49512
b2 coefficient = -1.02069
c12 coefficient = 0.00086665
Pressure
= 415 ADC counts
Temperature = 513 ADC counts
Pressure Compensation:
Pcomp = a0 + (b1 + c12 ⋅ Tadc) ⋅ Padc + b2 ⋅ Tadc
MPL115A1
10
Sensors
Freescale Semiconductor, Inc.