Bosch Sensortec"| BST-BMP581-DS004-02 17 | 74
Modifications reserved | Data subject to change
without notice Document number: BST-BMP581-DS004-02
4.3.4 NORMAL mode
Normal mode performs pressure measurements with a configurable frequency, which is the output data rate (ODR).
The ODR can be set in ODR_CONFIG.odr. Normal mode continuously cycles between an (active) measurement
period and an (inactive) standby period. In normal mode, the most recent measurement result can be directly obtained
from the data registers. Alternatively, the latest measurement results can be obtained from the FIFO.
Normal mode is recommended if pressure needs to be sampled in regular intervals, but none of the conditions apply
where FORCED and CONTINOUS mode may be favorable.
The ODR_CONFIG.odr register field is used to define the output data rate (ODR) if the BMP581. Data rates of
0.125Hz up to 240 can be selected. For the full list of available ODRs, see the register description. Not all
combinations of OSR and ODRs are valid, as measurement times may not fit into an ODR cycle. Table 7: maximum
nominal ODR setting per OSR settings in NORMAL modeshows the maximum ODR for a given ODR setting.
Table 7: maximum nominal ODR setting per OSR settings in NORMAL mode
[Hz]
OSR_P
Table 8: Maximum nominal ODR setting per OSR settings in NORMAL mode for temperature only measurements
[Hz]
Configuration Check. BMP581 has an automatic configuration checking, which is functional in NORMAL mode and
when both temperature and pressure measurements are enabled. If a configuration is not valid, this will be indicated
by the OSR_EFF.odr_is_valid register field. If a measurement with an invalid setting is started, the BMP581 will run
with the specified ODR, but use a default setting for the ODRs:
For ODRs ≥ 160Hz, both OSRs will be set to 1
For all ODRs <160Hz, both OSRs will be set to 2
The effective ODRs are available in the register fields OSR_EFF.osr_t_eff and OSR_EFF.osr_p_eff. This action of
alignment and check is done in NORMAL mode only.
4.3.5 Low Power NORMAL mode
If the conditions for deep standby apply, as described in 3.3.1 above, then NORMAL mode will automatically apply
DEEP_STANDY phase in between the measurements. This reduces power consumption even further. If one of these
settings is changed, the BMP581 transitions back to NORMAL mode.
4.3.6 CONTINOUS mode
Continuous mode performs pressure measurements simular to NORMAL mode. However, the ODR setting is ignored.
Sampling is performed with the maximum frequency that is possible with the selected oversampling settings.
CONTINOUS mode stays in the (active) measurement period and does not cycle to a standby period. The resulting