AK09912 Datasheet, PDF (17/42 Pages) HuaXinAn Electronics CO.,LTD – 3-axis Electronic Compass

[AK09912]
6.4.3. Continuous Measurement Mode 1, 2, 3 and 4
When Continuous measurement mode 1 (MODE[4:0]=“00010”), 2 (MODE[4:0]=“00100”), 3 (MODE[4:0]=“00110”) or 4
(MODE[4:0]=“01000”) is set, magnetic sensor measurement is started periodically at 10 Hz, 20 Hz, 50 Hz or 100 Hz
respectively. After magnetic sensor measurement and signal processing is finished, measurement magnetic data is stored to
measurement data registers (HXL to HZH) and all circuits except for the minimum circuit required for counting cycle
length are turned off (PD). When the next measurement timing comes, AK09912 wakes up automatically from PD and
starts measurement again. When temperature sensor is enabled (TEM =“1”), temperature sensor measurement is started
together with magnetic sensor measurement, and measurement temperature data is stored to measurement data registers
(TMPS).
Continuous measurement mode ends when Power-down mode (MODE[4:0]=“00000”) is set. It repeats measurement until
Power-down mode is set.
When Continuous measurement mode 1 (MODE[4:0]=“00010”), 2 (MODE[4:0]=“00100”), 3 (MODE[4:0]=“00110”) or 4
(MODE[4:0]=“01000”) is set again while AK09912 is already in Continuous measurement mode, a new measurement starts.
ST1, ST2 and measurement data registers (HXL to TMPS) will not be initialized by this.
(N-1)th
Nth
(N+1)th
PD
Measurement
PD
Measurement
PD
10Hz,20Hz,50Hz or 100Hz
Figure 6.4 Continuous measurement mode
6.4.3.1. Data Ready
When measurement data is stored and ready to be read, DRDY bit in ST1 register turns to “1”. This is called “Data Ready”.
DRDY pin is in the same state as DRDY bit. When measurement is performed correctly, AK09912 becomes Data Ready on
transition to PD after measurement.
MS1547-E-02
- 17 -
2014/7