AK9720 Datasheet, PDF (20/31 Pages) Asahi Kasei Microsystems – IR Sensor Module with I2C I/F

[AK9720]
5.2 Read-out data within a measurement period
The measurement data register is retained within a measurement period, so the data can
be read out within the measurement period. When data is read out within the measurement
period, the previous data retained is read out.
(N-1) (N)
(N+1)
PD _Measurement
SD
Measurement
SD
Measuremant data register
data(N-1)
data(N)
DRDY
Read-out data
ST1 data(N)
ST2
ST1 data(N)
ST2
Fig.7. Read-out data within a measurement period
5.3 Skipping Data
When measurement data is not read out between the end points of (N+1)^th and N^th
measurement, DRDY is held the until measurement data is read out. In this case, because
the N^th data was skipped, the DRDY bit is “1”. (Fig.8)
When a data read begins after the end of the N^th measurement, and when the data read
cannot be completed until the end of the (N+1) ^th measurement, the measurement data
registers are protected to read data normally. In this case, because the (N+1) ^th data has
been skipped, the DOR bit transitions to “1”. (Fig.9)
In both of these cases, the DOR bit changes to “0” from “1”, at the start of reading data if
DRDY is “1”.
(N-1) (N)
PD Measurement
PD
Measurement data registers
data(N-1)
data^(N)
(N+1)
Meas urem ent
PD
data(N+1)
DRDY
DOR
Read-out data
Fig.8. Skipping Data
ST1 data(N+1)
ST2
Rev.02
AKM Confidential
- 20 -
2012/11