AK8975 Datasheet, PDF (14/34 Pages) Asahi Kasei Microsystems – 3-axis Electronic Compass

[AK8975/C]
6.4.2.2. Data Error
When data reading is started out of data readable period, read data is not correct. In this case, DERR bit of ST2
register turns to “1” so that read data can be checked at the end of data reading. DERR turns to “0” when ST2
register is read.
(N-1)th Nth
(N+1)th
PD Measurement
PD
Measurement
PD
Data Readable Period
Data Readable Period
Measurement Data Register
(N-1)th Indefinite
Nth
Indefinite
(N+1)th
Ind
DRDY
DERR
Register Read
ST1 Data ST2
Register
ST1 Data ST2
Register
Figure 6.4 Data Error
ST1 Data ST2
Register


6.4.2.3. Magnetic Sensor Overflow
AK8975/C has the limitation for measurement range that the sum of absolute values of each axis should be
smaller than 2400μT.
|X|+|Y|+|Z| < 2400μT
When the magnetic field exceeded this limitation, data stored at measurement data are not correct. This is
called Magnetic Sensor Overflow.
When magnetic sensor overlow occurs, HOFL bit turns to “1”. When the next measurement starts, it returns to
“0”.
MS1187-E-02
- 14 -
2010/05