BMM350 datasheet(21/63 Pages) BOSCH

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Bosch Sensortec | BST-BMM350-DS001-27

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Document number: BST-BMM350-DS001-27

as well as in the event of applications for industrial property rights

INT_CTRL_IBI.clear_drdy_int_status_upon_ibi

allows to clear the interrupt status register automatically

upon sending an IBI.

An API function “BMM350_set_int_ctrl_ibi” is provided to configure and enable/disable the IBI.

5.6 Pad drive settings

To avoid problems with signal over- or undershoot with long wires the user can configure the relative pad driver strength

via register PAD_CTRL.drv<2:0>.Asetting of 0 selects the weakest drive strength, a setting of 7 selects the strongest

drive strength.

In I3C mode the user does not have control over the value of the pull-up resistor value, so care must be taken to not

select a too weak driver strength.

The default relative drive strength is 7 after boot.

An API function “BMM350_set_pad_drive” is provided to change the drive strength.

5.7 Enable/disable axis

The user can choose between converting all axes or only a selected set of axes.

Configuration is handled via register PMU_CMD.en_x/y/z .

An API function “BMM350_enable_axes” is provided to handle that configuration.

The function will ignore requests to disable all axes.

Enabling or disabling an axis is only working in suspend mode, a change on-the-fly in normal mode is ignored by the

sensor hardware.

The API function “BMM350_enable_axes” will turn the sensor into suspend mode, change the axes enable bits and

re-enable normal mode when the sensor is in normal mode at the moment the said API function is called.

5.8 Sensortime always available

For best power saving the internal clocks are only turned on when needed.

In suspend mode, all fast internal clocks are turned off, meaning that the sensortime counter is stopped.

User can decide to keep the main internal oscillator running, which makes sensortime information available all time.

An API function “BMM350_set_ctrl_user” is provided which makes sensortime all time available or not. The

sensortime reading is updated only when new data are available after data conversion.

5.9 I2C watchdog setting

When I2C communication stalls the bmm350 is able to reset the communication interface using a watchdog. It is possible

to choose between 2 timeout intervals, see register description I2C_WDT_SET.

An API function “BMM350_set_i2c_wdt” is provided to enable or disable the watchdog and choose the interval length.

5.10 Status information

A few registers provide status or error information.

5.10.1 CHIP_ID

CHIP_ID is located at address 0.

Its content is 0x33, read-only. This content is BST product-specific and helps e.g. to check initially whether the BMM350

is properly communicating with the host.

BMM350 Datasheet(PDF) 21 Page - Bosch Sensortec GmbH