Data Sheet BMA456 Digital, triaxial acceleration sensor Bosch Sensortec Data Sheet BMA456 Part number(s) 0 273 141 282 Document revision 1.1 Release date 26 October 2017 Document number BST-BMA456-DS000-01 Notes Subject to change without notice. Product photos and pictures are for illustration purposes only and may differ from the real product’s appearance.
Data Sheet BMA456 Page 2 BMA456 16 bit, digital, triaxial acceleration sensor with intelligent on-chip motion-triggered interrupt features optimized for wearable applications. Key features Small package size Digital interface Programmable functionality On-chip FIFO On-chip interrupt features Ultra-low power (Secondary) Auxiliary Interface RoHS compliant, halogen-free LGA package (12 pins), footprint 2mm x 2mm, height 0.
Data Sheet BMA456 Page 3 Table of contents 1. SPECIFICATION............................................................................................................................. 7 2. ABSOLUTE MAXIMUM RATINGS .............................................................................................. 10 3. QUICK START GUIDE ................................................................................................................. 11 Note about using the BMA456: .........................
Data Sheet BMA456 4.9. Page 4 SENSOR SELF-TEST ............................................................................................................ 49 4.10. OFFSET COMPENSATION ..................................................................................................... 50 Manual Offset Compensation ................................................................................................... 50 Inline Calibration .....................................................................
Data Sheet BMA456 Page 5 Register (0x41) ACC_RANGE .................................................................................................. 80 Register (0x44) AUX_CONF ..................................................................................................... 81 Register (0x45) FIFO_DOWNS ................................................................................................ 81 Register (0x46) FIFO_WTM_0 .........................................................................
Data Sheet BMA456 Page 6 SPI ......................................................................................................................................... 116 I2C.......................................................................................................................................... 117 7.3. CONNECTION DIAGRAMS WITH AUXILIARY INTERFACE .......................................................... 117 SPI ............................................................................
Data Sheet BMA456 Page 7 1. Specification Unless stated otherwise, the given values are over lifetime, operating temperature and voltage ranges. Minimum/maximum values are ±3.
Data Sheet BMA456 Operating Temperature TA Page 8 -40 +85 °C OUTPUT SIGNAL Parameter Sensitivity Sensitivity Temperature Drift Zero-g Offset Zero-g Offset Temperature Drift Output Data Rate Output data rate and BW in Performance mode Symbol S2g S4g S8g S16g TCS Condition gFS2g, TA=25°C gFS4g, TA=25°C gFS8g, TA=25°C gFS16g, TA=25°C Off Nominal VDD and VDDIO, 25°C, gFS4g X/Y - Axes 20 mg 0.2 mg/K Z-Axis 0.35 mg/K TCO ODRPERF ODR12.
Data Sheet BMA456 Parameter Cross Axis Sensitivity Symbol S Alignment Error EA BST-BMA456-DS000-01 | Version 1.1 | October 2017 MECHANICAL CHARACTERISTICS Condition Min relative contribution between any two of the three axes relative to package outline Page 9 Typ 0.5 0.5 Max Units % ° Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties.
Data Sheet BMA456 Page 10 2. Absolute maximum ratings Absolute maximum ratings Parameter Condition Min Voltage at Supply Pin VDD Pin VDDIO Pin Voltage at any Logic Pin Passive Storage Temp. Range None-volatile memory (NVM) Data Retention Mechanical Shock Non-Supply Pin -0.3 ≤ 65% rel. H. -50 T = 85°C, 10 after 15 cycles Duration ≤ 200µs Duration ≤ 1.0ms Free fall onto hard surfaces HBM CDM MM ESD, at any pin -0.3 -0.3 Max Units 4 4 V V VDDIO+0.3, <4 +150 V °C y 10,000 2,000 1.
Data Sheet BMA456 Page 11 3. Quick Start Guide The purpose of this chapter is to help developers who want to start working with the BMA456 by giving you some very basic hands-on application examples to get started. Note about using the BMA456: The communication between application processor and BMA456 will happen either over i2c or spi interface. For more information about the interfaces, read the related chapter 6.
Data Sheet BMA456 Page 12 start disable PWR_ CONF.adv_power_save write_reg(addr=0x7C,val=0x00) sleep(500us) write_reg(addr=0x59,val=0x00) init_array[]=read_file(init_file) wait for 500us prepare feature engine INIT_CTRL=0x00 load config file and save as array (little endian) (for config file see chapter 4.2) burst write to reg FEATURES_IN burst_write_reg(addr=0x5E,val=init_array[]) enable sensor features write_reg(addr=0x59,val=0x01) End c.
Data Sheet BMA456 Page 13 Example 2: Reading acceleration data from BMA456 (example: low power mode) -setting data processing parameters (power, bandwidth, range) and reading sensor data start enable acquisiton of acceleration data.
Data Sheet BMA456 Page 14 Further steps: The BMA456 has many more capabilities that are described in this document and include FIFO, power saving modes, synchronization capabilities with host processor, data synchronization and integration with third party sensors, many interrupts generation and more features like step counter, etc. BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights.
Data Sheet BMA456 Page 15 4. Functional Description Block Diagram SENSORTIME Accel ADC select SENSOR DATA AND SENSORTIME REGISTER SPI / I2C DIGITAL SIGNAL CONDITIONING FIFO ENGINE INT1, INT2 EXTERNAL MAGNET DATA PRIMARY DIGITAL INTERFACE Feature engine RAW DATA SECONDARY DIGITAL INTERFACE CONFIGURABLE AS: MAGNET (I2C MASTER) MAGNET (I2C) Magnet BST-BMA456-DS000-01 | Version 1.
Data Sheet BMA456 Page 16 4.1. Supply Voltage and Power Management BMA456 has two distinct power supply pins: VDD is the main power supply. VDDIO is a separate power supply pin used for supplying power for the interface including the auxiliary interface. There are no limitations with respect to the voltage level applied to the VDD and VDDIO pins, as long as it lies within the respective operating range.
Data Sheet BMA456 Page 17 4.2. Device Initialization After power up sequence the accelerometer is in suspend mode, device must initialized through the following procedure. Initialization has to be performed as well after every POR or soft reset. Disable advanced power save mode: PWR_CONF.adv_power_save =0b0 Wait for 450 us. The register SENSORTIME_0 increments every 39.25 µsec and may be used for accurate timing. Write INIT_CTRL.
Data Sheet BMA456 Page 18 4.3. Power Modes The power state of the BMA456 is controlled through the registers PWR_CONF and PWR_CTRL. The Register PWR_CTRL enables and disables the accelerometer and the auxiliary sensor. The Register PWR_CONF controls which power state the sensors enter if they are enabled or disabled in the Register PWR_CTRL. The power state impacts the behavior of the sensor with respect to start-up time, available functions, etc. but not the sensor data quality.
Data Sheet BMA456 Page 19 The auxiliary sensor functionality is supported only when the auxiliary interface is connected for the auxiliary sensor operation. If the auxiliary interface is not used for auxiliary sensor operation, then the auxiliary sensor interface must remain disabled by setting PWR_CTRL.aux_en=0b0 (default). To change the power mode of the auxiliary sensor, both the power mode of the auxiliary interface and the auxiliary sensor part needs to be changed, e.g.
Data Sheet BMA456 Page 20 4.4. Sensor Data Acceleration Data The width of acceleration data is 16 bits given in two´s complement representation in the registers DATA_8 to DATA_13. The 16 bits for each axis are split into an MSB upper part and an LSB lower part. Reading the acceleration data registers shall always start with the LSB part. In order to ensure the integrity of the acceleration data, the content of an MSB register is locked by reading the corresponding LSB register (shadowing procedure).
Data Sheet BMA456 Page 21 Accelerometer data processing for low power mode Low power mode can be enabled by PWR_CONF.adv_power_save=0b1 and ACC_CONF.acc_perf_mode=0b0. In this power mode, the accelerometer regularly changes between a suspend power mode phase where no measurement is performed and a performance power mode phase, where data is acquired. The period of the duty cycle for changing between suspend and performance mode will be determined by the output data rate (ACC_CONF.acc_odr).
Data Sheet BMA456 Page 22 Sensor Time The BMA456 supports the concept of sensortime. Its core element is a free running counter with a width of 24 bits. It increments with a resolution of 39.0625us. The user can access the current state of the counter by reading registers SENSORTIME_0 to SENSORTIME_2. All sensor events e.g. updates of data registers are synchronous to this sensor time register as defined in the table below.
Data Sheet BMA456 Page 23 1/fODR, new 1/fODR Currently active ODR Current ODR > requested ODR Configuration change including ODR change written to register Confguration change becomes effective requested ODR t 1/fODR 1/fODR, new Currently active ODR Requested ODR > current ODR Configuration change including ODR change written to register requested ODR Confguration change becomes effective t 1/fODR Configuration change w/o ODR change Currently active ODR requested ODR Configuration change writt
Data Sheet BMA456 Page 24 4.5. FIFO The device supports the following FIFO operating modes: Streaming mode: overwrites oldest data on FIFO full condition FIFO mode: discards newest data on FIFO full condition The FIFO depth is 1024 byte and supports the following interrupts: FIFO full interrupt FIFO watermark interrupt FIFO is enabled with FIFO_CONFIG_1.fifo_acc_en=0b1 (0b0= disabled). To enable the FIFO for the auxiliary interface (magnetometer) set FIFO_CONFIG_1.fifo_aux_en=0b1 (0b0=disabled).
Data Sheet BMA456 Page 25 When FIFO__data is 0b1 (0b0) data for sensor x is included (not included) in the data part of the frame. The fh_ext<1:0> field are used for external tagging. The data format for data frames is identical to the format defined for the Register (0x0A) DATA_0 to Register (0x17) DATA_13 register. Only frames which contain data of at least one sensor will be written into the FIFO. E.g. fh_parm=0b0101 the data in the frame are shown below.
Data Sheet BMA456 Page 26 If the auxiliary sensor interface is enabled, the number of auxiliary sensor bytes in a FIFO frame is always AUX_IF_CONF.aux_rd_burst bytes (see chapter 4.8). If the burst length is less than 8, BMA456 will pad the values read form the auxiliary sensor. E.g. if AUX_IF_CONF.
Data Sheet BMA456 Page 27 Conditions and Details Frame rates The frame sampling rate of the FIFO is defined by the maximum output data rate of the sensors enabled for FIFO sampling. The FIFO sampling configuration is set in register FIFO_CONFIG_0 to FIFO_CONFIG_1. It is possible to select filtered or pre-filtered data as an input to the FIFO. If unfiltered data are selected in register FIFO_DOWNS.acc_fifo_filt_data for the accelerometer, the sample rate is 1600 Hz.
Data Sheet BMA456 Page 28 Skip Frame (fh_parm=0x0): In the case of FIFO overflows, a skip_frame is prepended to the FIFO content, when read out next time. The data for the frame consists of one byte and contains the number of skipped frames. When more than 0xFF frames have been skipped, 0xFF is returned. A skip frame is expected always as first frame in a FIFO read burst. A skip frame does not consume memory in the FIFO.
Data Sheet BMA456 Page 29 Sample drop frames will be inserted only for transition phases after configuration changes, not for samples dropped between sensor enable and first valid sample. For a detailed description of configuration changes see Section 4.4, Subsection “Configuration Changes”. FIFO Partial frame reads When a frame is only partially read through the Register FIFO_DATA it will be repeated completely with the next access both in headerless and in header mode.
Data Sheet BMA456 Page 30 FIFO synchronization with external interrupts External interrupts may be synchronized into the FIFO data. For this operation mode the FIFO_CONFIG_1.fifo_tag_int1_en and FIFO_CONFIG_1.fifo_tag_int2_en need to be enabled, as well as INT1_IO_CTRL.input_en and INT2_IO_CTRL.input_en. The fh_ext field in FIFO header will then be set according to the signal at the INT1/INT2 inputs.
Data Sheet BMA456 Page 31 4.6. Interrupt Features Global Configuration The configuration of the interrupt feature engine is described in the Register FEATURES_IN. In order to reconfigure the features, the user must perform a burst read of the whole content from the Register FEATURES_IN, followed by a modification of the content, and finally a burst write of the modified content to the Register FEATURES_IN.
Data Sheet BMA456 Page 32 Axes remapping for interrupt features If the sensor orientation is different than described in chapter 8.2 the sensor axis must be remapped to use the integrated features. Axes remapping register allows the host to freely map individual axis to the coordinate system of the used platform. Individual axis can be mapped to any other defined axis. The sign value of the axis can be also configured. For example x axis can be mapped to –x axis, +y axis, - y axis, +z axis or –z axis.
Data Sheet BMA456 Page 33 Step Detector / Step Counter The Step Counter algorithm is optimized on high accuracy, while Step Detector is optimized on low latency. Both are running in parallel, once enabled, but the Step Detector interrupt output is mutually exclusive with the Step Counter watermark interrupt. The Step Counter is optimized for wearable devices and wrist use case. In addition the Step Counter implements the function required for step counting in Android 4.
Data Sheet BMA456 Parameter Name PARAM_1 PARAM_2 PARAM_3 PARAM_4 PARAM_5 PARAM_6 PARAM_7 PARAM_8 PARAM_9 PARAM_10 PARAM_11 PARAM_12 PARAM_13 PARAM_14 PARAM_15 PARAM_16 PARAM_17 PARAM_18 PARAM_19 PARAM_20 PARAM_21 PARAM_22 PARAM_23 PARAM_24 PARAM_25 Page 34 Phone Configuration Wrist Configuration 306 301 30950 31700 132 315 27804 31451 7 4 30052 31551 32426 27853 1375 1219 2750 2437 1375 1219 -5994 -6420 16879 17932 1 1 12 39 12 25 74 150 160 160 0 1 12 12 15600 1560
Data Sheet BMA456 Page 35 Configuration settings: 1. FEATURES_IN.step_counter.settings_26.watermark_level - Watermark level; the Stepcounter will trigger output every time this number of steps are counted. Holds implicitly a 20x factor, so the range is 0 to 20460, with resolution of 20 steps. If 0, the Step Counter watermark is disabled and Step Detector enabled. 2. FEATURES_IN.step_counter.settings_26.reset_counter – flag to reset the counted steps.
Data Sheet BMA456 Page 36 Walking activity recognition This feature can detect the actual walking activity status of a user. It can distinguish between walking, running and still. The change of the status can be read in INT_STATUS_0.activity_type_out; the status itself can be read in ACTIVITY_TYPE.activity_type_out. The walking activity recognition can be enabled by FEATURES_IN.step_counter.settings_26.en_activity. Step counter has to be enabled as well by FEATURES_IN.step_counter__settings_26.en_counter.
Data Sheet BMA456 Page 37 Tilt on Wrist How to perform the “Tilt on Wrist” gesture ideally: 1. Wrap the device on your wrist. 2. Lift the hand wearing the device up to a comfortable position and tilt it to minimum 12° to gravity (see the image below for the valid position) 3. Wait for a second. Wrist rotation Portrait up Sensor Min 12° g Valid position for Tilt on Wrist The Tilt on Wrist Interrupt is detected with one accelerometer axis.
Data Sheet BMA456 Portrait up 2 Top layer Pin#1 Marking g Portrait up Pin#1 Marking 3 Top layer g Portrait up 4 Pin#1 Marking g Portrait up Top layer Pin#1 Marking Bottom layer 5 g Portrait up 6 Bottom layer Pin#1 Marking g Portrait up Pin#1 Marking Bottom layer 7 g BST-BMA456-DS000-01 | Version 1.
Data Sheet BMA456 Portrait up 8 g Pin#1 Marking Bottom layer map_x_axis = 0 map_x_axis_sign = 0 map_y_axis = 1 map_y_axis_sign = 1 map_z_axis = 2 map_z_axis_sign = 1 Page 39 X = x axis Y = -y axis Z = -z axis y, z inverted Configuration settings FEATURES_IN.wrist_tilt.settings.enable – enables/disables the Tilt on Wrist feature. BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights.
Data Sheet BMA456 Page 40 Double tap / Tap detection The gesture “Tap / Double tap” can be enabled by FEATURES_IN.tap_doubletap.settings.enable. The detection is done by measuring the acceleration on z-direction. By default double tap detection is enabled. To enable single tap detection (and disable double tap), you can configure the parameter: FEATURES_IN.tap_doubletap.settings.single_tab_en – 1 bit – flag. The detection sensitivity can be customized using the register FEATURES_IN.tap_doubletap.settings.
Data Sheet BMA456 Page 41 Any Motion / No motion detection Any Motion Detection: The any-motion detection uses the slope between two acceleration signals to detect changes in motion. The interrupt is configured by setting at least one of the following flags: FEATURES_IN.any_motion.settings_2.en_x, FEATURES_IN.any_motion.settings_2.en_y and FEATURES_IN.any_motion.settings_2.en_z, respectively for each axis.
Data Sheet BMA456 Page 42 No Motion Detection: The interrupt engine can also be configured as a No-motion interrupt, when register FEATURES_IN.any_motion.settings_1.nomotion_sel is set. No-motion is generated when the slope on all selected axis remains smaller than a programmable FEATURES_IN.any_motion.settings_1.threshold for a programmable time. The signals and timings relevant to the no-motion interrupt functionality are depicted in the figure below.
Data Sheet BMA456 Page 43 4.7. General Interrupt Pin configuration Electrical Interrupt Pin Behavior Both interrupt pins INT1 and INT2 can be configured to show the desired electrical behavior. Interrupt pins can be enabled in INT1_IO_CTRL.output_en respectively INT2_IO_CTRL.output_en. The characteristic of the output driver of the interrupt pins may be configured with bits INT1_IO_CTRL.od and INT2_IO_CTRL.od.
Data Sheet BMA456 Page 44 4.8. Auxiliary Sensor Interface The auxiliary interface allows to attach one auxiliary sensor (e.g. magnetometer) on dedicated auxiliary sensor interface as shown in Figure… Application Processor I2C or SPI primary interface BMA456 I2C auxiliary interface BMM150 6-DOF Solution w/ BMA456 and BMM150 Structure and Concept The BMA456 controls the data acquisition of the auxiliary sensor and presents the data to the application processor through the primary I2C or SPI interface.
Data Sheet BMA456 Page 45 measurement of the auxiliary sensor using the auxiliary sensor forced mode and the data readout from the auxiliary sensor (data mode). In setup mode, the auxiliary sensor may be configured and trim data may be read out from the auxiliary sensor. In the data mode the auxiliary sensor data are continuously copied into BMA456 registers and may be read out from BMA456 directly over the primary interface.
Data Sheet BMA456 Page 46 Configuration phase of the auxiliary sensor. Example: Read bytes 5 and 6 of auxiliary sensor check that no manual auxiliary sensor op is running start I2C_READ( STATUS, 1) Yes STATUS.
Data Sheet BMA456 Page 47 Example: Write 0xEF into byte 3 of auxiliary sensor start check that no manual auxiliary sensor op is running I2C_READ(STATUS, 1) Yes STATUS<2>=1 ? No enable reads/writes I2C_READ(STATUS, 1) I2C_WRITE(AUX_IF_CONF, 0b01000000) write data to be written into BMA423 I2C_WRITE(AUX_WR_DATA, 0xEF) Issue I2C operation for byte 3 on auxiliary sensor I2C_WRITE(AUX_WR_ADDR, 0b00000011) Check if write completed (optional) I2C_READ(STATUS, 1) No STATUS<2>=1 ? Yes I2C_READ(STA
Data Sheet BMA456 Page 48 Data mode (AUX_IF_CONF.aux_manual_en=0) AUX_RD_ADDR.read_addr defines the address of the data register from which to read the number of data bytes configured in AUX_IF_CONF.aux_rd_burst from AUX_0… AUX_7 data of the auxiliary sensor. These data are stored in the DATA_0 up to DATA_7 register. The data ready status is set in STATUS.drdy_aux, it is typically cleared through reading one of the DATA_0 to DATA_7 registers. AUX_WR_ADDR.
Data Sheet BMA456 Page 49 4.9. Sensor Self-Test The BMA456 has a comprehensive self test function for the MEMS element by applying electrostatic forces to the sensor core instead of external accelerations. By actually deflecting the seismic mass, the entire signal path of the sensor can be tested.
Data Sheet BMA456 Page 50 4.10. Offset Compensation BMA456 offers manual compensation as well as inline calibration. Offset compensation is performed with pre-filtered data, and the offset is then applied to both, prefiltered and filtered data. If necessary the result of this computation is saturated to prevent any overflow errors (the smallest or biggest possible value is set, depending on the sign).
Data Sheet BMA456 Page 51 4.11. Non-Volatile Memory The registers NV_CONF and OFFSET_0 to OFFSET_2 have an NVM backup which are accessible by the user. The content of the NVM is loaded to the image registers after a reset (either POR or softreset). As long as the image update is in progress, STATUS.cmd_rdy is 0b0, otherwise it is 0b1. The image registers can be read and written like any other register. Writing to the NVM is a 4-step procedure: 1. Set PWR_CONF.adv_power_save = 0b0 2.
Data Sheet BMA456 Page 52 5. Register Description 5.1. General Remarks Registers can be read and written in all power configurations with the exception of FEATURES_IN and FIFO_DATA which need PWR_CONF.adv_power_save set to 0b0. 5.2.
Data Sheet BMA456 Page 53 INTERN 0x5F AL_ERR 0x00 reserved int_err_2 int_err_1 reserved reserved int1_drdy int1_fwm int1_ffull wrist_tilt_ activity_t step_cou out ype_out nter_out wrist_tilt_ activity_t step_cou out ype_out nter_out OR 0x5E FEATUR ES_IN 0x00 features_in 0x5D - - reserved ...
Data Sheet BMA456 0x47 0x46 0x45 0x44 0x43 0x42 0x41 0x40 FIFO_W TM_1 FIFO_W TM_0 FIFO_D OWNS AUX_CO NF 0x02 Page 54 reserved fifo_water_mark_12_8 0x00 0x80 fifo_water_mark_7_0 acc_fifo_ acc_fifo_downs filt_data 0x46 reserved aux_offset aux_odr - - reserved - - reserved ACC_RA NGE ACC_CO NF 0x01 0xA8 reserved acc_perf acc_range acc_bwp _mode acc_odr 0x3F - - reserved ...
Data Sheet BMA456 Page 55 STEP_C 0x1E OUNTER 0x00 step_counter_out_0 _0 0x1D 0x1C 0x1B 0x1A 0x19 0x18 INT_STA TUS_1 INT_STA TUS_0 EVENT SENSOR TIME_2 SENSOR TIME_1 SENSOR TIME_0 0x00 0x00 acc_drdy _int error_int _out reserved any_no_ motion_o ut aux_drdy reserved _int wakeup_ out 0x01 reserved wrist_tilt_ activity_t step_cou out ype_out nter_out sensor_time_23_16 0x00 sensor_time_15_8 0x00 sensor_time_7_0 DATA_13 0x00 acc_z_15_8 0x16 DATA_12 0x00 acc_z_7_0 0x15 DATA_11
Data Sheet BMA456 Page 56 FEATURES_IN Register Register Default Address Name Value 7 6 5 4 3 2 1 0 general_ 0x5E: 0x3F settings. axes_re 0x00 map_z_a reserved xis_sign mapping[ 1] general_ 0x5E: 0x3E settings. axes_re 0x88 map_z_axis mapping[ map_y_a xis_sign map_y_axis map_x_a xis_sign map_x_axis 0] general_ 0x5E: settings.c 0x3D onfig_id[ 0x00 identification 0x00 identification 0x00 reserved 1] general_ 0x5E: settings.
Data Sheet BMA456 Page 57 step_cou 0x5E: nter.setti 0x34 ngs_25[0 0x0E param_25 0x00 param_24 0x01 param_24 0x00 param_23 0x03 param_23 0x00 param_22 0x01 param_22 0x01 param_21 0x00 param_21 0x3C param_20 0xF0 param_20 ] step_cou 0x5E: nter.setti 0x33 ngs_24[1 ] step_cou 0x5E: nter.setti 0x32 ngs_24[0 ] step_cou 0x5E: nter.setti 0x31 ngs_23[1 ] step_cou 0x5E: nter.setti 0x30 ngs_23[0 ] step_cou 0x5E: nter.setti 0x2F ngs_22[1 ] step_cou 0x5E: nter.
Data Sheet BMA456 Page 58 step_cou 0x5E: nter.setti 0x29 ngs_19[1 0x00 param_19 0x0C param_19 0x00 param_18 0x01 param_18 0x00 param_17 0xA0 param_17 0x00 param_16 0x96 param_16 0x00 param_15 0x19 param_15 0x00 param_14 ] step_cou 0x5E: nter.setti 0x28 ngs_19[0 ] step_cou 0x5E: nter.setti 0x27 ngs_18[1 ] step_cou 0x5E: nter.setti 0x26 ngs_18[0 ] step_cou 0x5E: nter.setti 0x25 ngs_17[1 ] step_cou 0x5E: nter.setti 0x24 ngs_17[0 ] step_cou 0x5E: nter.
Data Sheet BMA456 Page 59 step_cou 0x5E: nter.setti 0x1E ngs_14[0 0x27 param_14 0x00 param_13 0x01 param_13 0x46 param_12 0x0C param_12 0xE6 param_11 0xEC param_11 0x04 param_10 0xC3 param_10 0x09 param_9 0x85 param_9 0x04 param_8 ] step_cou 0x5E: nter.setti 0x1D ngs_13[1 ] step_cou 0x5E: nter.setti 0x1C ngs_13[0 ] step_cou 0x5E: nter.setti 0x1B ngs_12[1 ] step_cou 0x5E: nter.setti 0x1A ngs_12[0 ] step_cou 0x5E: nter.
Data Sheet BMA456 0x5E: 0x12 0x5E: 0x11 0x5E: 0x10 0x5E: 0x0F 0x5E: 0x0E 0x5E: 0x0D 0x5E: 0x0C 0x5E: 0x0B 0x5E: 0x0A 0x5E: 0x09 0x5E: 0x08 0x5E: 0x07 0x5E: 0x06 0x5E: 0x05 0x5E: 0x04 Page 60 step_cou nter.setti 0xC3 param_8 0x6C param_7 0xCD param_7 0x7B param_6 0x3F param_6 0x00 param_5 0x04 param_5 0x7A param_4 0xDB param_4 0x01 param_3 0x3B param_3 0x7B param_2 0xD4 param_2 0x01 param_1 0x2D param_1 ngs_8[0] step_cou nter.setti ngs_7[1] step_cou nter.
Data Sheet BMA456 0x5E: 0x03 0x5E: 0x02 0x5E: 0x01 0x5E: 0x00 Page 61 any_moti on.settin 0x00 z_en y_en x_en duration gs_2[1] any_moti on.settin 0x05 duration gs_2[0] any_moti on.settin 0x00 gs_1[1] reserved nomotion _sel threshold any_moti on.settin 0xAA threshold gs_1[0] BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights.
Data Sheet BMA456 Page 62 Register (0x00) CHIP_ID DESCRIPTION: Chip identification code RESET: 0x16 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x00) CHIP_ID 7 6 R R 0 0 chip_id 3 2 R R 0 1 chip_id 5 R 0 4 R 1 1 R 1 0 R 0 5 n/a 0 reserved 1 R 0 cmd_err 4 R 0 error_code 0 R 0 fatal_err chip_id: Chip identification code for BMA456.
Data Sheet BMA456 Page 63 aux_err: Error in I2C-Master detected. This flag will be reset when read. Register (0x03) STATUS DESCRIPTION: Sensor status flags RESET: 0x10 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x03) STATUS 7 6 R n/a 0 0 drdy_acc reserved 3 2 n/a R 0 0 reserved aux_man_op 5 R 0 drdy_aux 1 n/a 0 reserved 4 R 1 cmd_rdy 0 n/a 0 aux_man_op: ‘1’(‘0’) indicate a (no) manual auxiliary interface operation is ongoing.
Data Sheet BMA456 Page 64 Register (0x0B) DATA_1 DESCRIPTION: AUX_X(MSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x0B) DATA_1 7 6 R R 0 0 aux_x_15_8 3 2 R R 0 0 aux_x_15_8 5 R 0 4 R 0 1 R 0 0 R 0 5 R 0 4 R 0 1 R 0 0 R 0 Register (0x0C) DATA_2 DESCRIPTION: AUX_Y(LSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x0C) DATA_2
Data Sheet BMA456 Page 65 Register (0x0D) DATA_3 DESCRIPTION: AUX_Y(MSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x0D) DATA_3 7 6 R R 0 0 aux_y_15_8 3 2 R R 0 0 aux_y_15_8 5 R 0 4 R 0 1 R 0 0 R 0 5 R 0 4 R 0 1 R 0 0 R 0 Register (0x0E) DATA_4 DESCRIPTION: AUX_Z(LSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x0E) DATA_4
Data Sheet BMA456 Page 66 Register (0x0F) DATA_5 DESCRIPTION: AUX_Z(MSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x0F) DATA_5 7 6 R R 0 0 aux_z_15_8 3 2 R R 0 0 aux_z_15_8 5 R 0 4 R 0 1 R 0 0 R 0 5 R 0 4 R 0 1 R 0 0 R 0 Register (0x10) DATA_6 DESCRIPTION: AUX_R(LSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x10) DATA_6
Data Sheet BMA456 Page 67 Register (0x11) DATA_7 DESCRIPTION: AUX_R(MSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x11) DATA_7 7 6 R R 0 0 aux_r_15_8 3 2 R R 0 0 aux_r_15_8 5 R 0 4 R 0 1 R 0 0 R 0 5 R 0 4 R 0 1 R 0 0 R 0 Register (0x12) DATA_8 DESCRIPTION: ACC_X(LSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x12) DATA_8
Data Sheet BMA456 Page 68 Register (0x13) DATA_9 DESCRIPTION: ACC_X(MSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x13) DATA_9 7 6 R R 0 0 acc_x_15_8 3 2 R R 0 0 acc_x_15_8 5 R 0 4 R 0 1 R 0 0 R 0 5 R 0 4 R 0 1 R 0 0 R 0 Register (0x14) DATA_10 DESCRIPTION: ACC_Y(LSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x14) DATA_
Data Sheet BMA456 Page 69 Register (0x15) DATA_11 DESCRIPTION: ACC_Y(MSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x15) DATA_11 7 6 R R 0 0 acc_y_15_8 3 2 R R 0 0 acc_y_15_8 5 R 0 4 R 0 1 R 0 0 R 0 5 R 0 4 R 0 1 R 0 0 R 0 Register (0x16) DATA_12 DESCRIPTION: ACC_Z(LSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x16) DAT
Data Sheet BMA456 Page 70 Register (0x17) DATA_13 DESCRIPTION: ACC_Z(MSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x17) DATA_13 7 6 R R 0 0 acc_z_15_8 3 2 R R 0 0 acc_z_15_8 5 R 0 4 R 0 1 R 0 0 R 0 5 R 0 4 R 0 1 R 0 0 R 0 Register (0x18) SENSORTIME_0 DESCRIPTION: Sensor time <7:0> RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Registe
Data Sheet BMA456 Page 71 Register (0x19) SENSORTIME_1 DESCRIPTION: Sensor time <15:8> RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x19) SENSORTIME_1 7 6 R R 0 0 sensor_time_15_8 3 2 R R 0 0 sensor_time_15_8 5 R 0 4 R 0 1 R 0 0 R 0 5 R 0 4 R 0 1 R 0 0 R 0 sensor_time_15_8: Sensor time <15:8> in units of 10 ms.
Data Sheet BMA456 Page 72 Register (0x1B) EVENT DESCRIPTION: Sensor status flags RESET: 0x01 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x1B) EVENT 7 6 n/a n/a 0 0 reserved 3 2 n/a n/a 0 0 reserved 5 n/a 0 4 n/a 0 1 n/a 0 0 R 1 por_detected por_detected: '1' after device power up or softreset. Clear-on-read Register (0x1C) INT_STATUS_0 DESCRIPTION: Interrupt/Feature Status. Will be cleared on read.
Data Sheet BMA456 Page 73 Register (0x1D) INT_STATUS_1 DESCRIPTION: Interrupt Status. Will be cleared on read.
Data Sheet BMA456 Page 74 Register (0x1F) STEP_COUNTER_1 DESCRIPTION: Step counting value byte-1 RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x1F) STEP_COUNTER_1 7 6 R R 0 0 step_counter_out_1 3 2 R R 0 0 step_counter_out_1 5 R 0 4 R 0 1 R 0 0 R 0 5 R 0 4 R 0 1 R 0 0 R 0 step_counter_out_1: Step counting value byte-1 Register (0x20) STEP_COUNTER_2 DESCRIPTION: Step counting value byte-2 RESET: 0x00 DEFINITION (
Data Sheet BMA456 Page 75 Register (0x21) STEP_COUNTER_3 DESCRIPTION: Step counting value byte-3 RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x21) STEP_COUNTER_3 7 6 R R 0 0 step_counter_out_3 3 2 R R 0 0 step_counter_out_3 5 R 0 4 R 0 1 R 0 0 R 0 step_counter_out_3: Step counting value byte-3 (most significant byte) Register (0x22) TEMPERATURE DESCRIPTION: Contains the temperature value of the sensor RESET: 0x00 D
Data Sheet BMA456 Page 76 Register (0x24) FIFO_LENGTH_0 DESCRIPTION: FIFO byte count register (LSB) RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x24) FIFO_LENGTH_0 7 6 R R 0 0 fifo_byte_counter_7_0 3 2 R R 0 0 fifo_byte_counter_7_0 5 R 0 4 R 0 1 R 0 0 R 0 fifo_byte_counter_7_0: Current fill level of FIFO buffer.
Data Sheet BMA456 Page 77 Register (0x26) FIFO_DATA DESCRIPTION: FIFO data output register RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x26) FIFO_DATA 7 6 R R 0 0 fifo_data 3 2 R R 0 0 fifo_data 5 R 0 4 R 0 1 R 0 0 R 0 fifo_data: FIFO read data.
Data Sheet BMA456 Page 78 Register (0x2A) INTERNAL_STATUS DESCRIPTION: Error bits and message indicating internal status RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Register (0x2A) INTERNAL_STATUS 7 6 R R 0 0 odr_high_error odr_50hz_error Bit Read/Write Reset Value Content 3 R 0 message 2 R 0 5 R 0 axes_remap_erro r 1 R 0 4 R 0 message 0 R 0 message: Internal Status Message message 0x00 not_init ASIC is not initialized 0x01 init_ok ASIC initialized 0x02 init
Data Sheet BMA456 Page 79 Register (0x40) ACC_CONF DESCRIPTION: Sets the output data rate, the bandwidth, and the read mode of the acceleration sensor RESET: 0xA8 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x40) ACC_CONF 7 6 RW RW 1 0 acc_perf_mode acc_bwp 3 2 RW RW 1 0 acc_odr 5 RW 1 4 RW 0 1 RW 0 0 RW 0 acc_odr: ODR in Hz.
Data Sheet BMA456 0x02 0x03 0x04 0x05 0x06 0x07 norm_avg4 acc_perf_mode samples cic_avg8 acc_perf_mode samples res_avg16 acc_perf_mode samples res_avg32 acc_perf_mode samples res_avg64 acc_perf_mode samples res_avg128 acc_perf_mode samples Page 80 = 1 -> normal mode; acc_perf_mode = 0 -> average 4 = 1 -> Reserved; acc_perf_mode = 0 -> average 8 = 1 -> Reserved; acc_perf_mode = 0 -> average 16 = 1 -> Reserved; acc_perf_mode = 0 -> average 32 = 1 -> Reserved; acc_perf_mode = 0 -> average 64 = 1 -> Reserv
Data Sheet BMA456 Page 81 Register (0x44) AUX_CONF DESCRIPTION: Sets the output data rate of the Auxiliary interface RESET: 0x46 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x44) AUX_CONF 7 6 RW RW 0 1 aux_offset 3 2 RW RW 0 1 aux_odr 5 RW 0 4 RW 0 1 RW 1 0 RW 0 aux_odr: Select the poll rate for the sensor attached to the Auxiliary interface.
Data Sheet BMA456 Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x45) FIFO_DOWNS 7 6 RW RW 1 0 acc_fifo_filt_data acc_fifo_downs 3 2 n/a n/a 0 0 reserved Page 82 5 RW 0 4 RW 0 1 n/a 0 0 n/a 0 acc_fifo_downs: Downsampling for accelerometer data (2**acc_fifo_downs) acc_fifo_filt_data: selects filtered or unfiltered Accelerometer data for fifo acc_fifo_filt_data 0x00 unfiltered Unfiltered data 0x01 filtered Filtered data Register (0x46) FIFO_WTM_0 DESCRIPTION: FI
Data Sheet BMA456 Page 83 Register (0x47) FIFO_WTM_1 DESCRIPTION: FIFO Watermark level MSB RESET: 0x02 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Register (0x47) FIFO_WTM_1 7 6 n/a n/a 0 0 reserved Bit Read/Write Reset Value Content 3 2 RW RW 0 0 fifo_water_mark_12_8 5 n/a 0 1 RW 1 4 RW 0 fifo_water_mark_ 12_8 0 RW 0 5 n/a 0 4 n/a 0 1 RW 1 fifo_time_en 0 RW 0 fifo_stop_on_full Register (0x48) FIFO_CONFIG_0 DESCRIPTION: FIFO frame content configuration RESET: 0x02 D
Data Sheet BMA456 Page 84 Register (0x49) FIFO_CONFIG_1 DESCRIPTION: FIFO frame content configuration RESET: 0x10 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x49) FIFO_CONFIG_1 7 6 n/a RW 0 0 reserved fifo_acc_en 3 2 RW RW 0 0 fifo_tag_int1_en fifo_tag_int2_en 5 RW 0 fifo_aux_en 1 n/a 0 reserved 4 RW 1 fifo_header_en 0 n/a 0 fifo_tag_int2_en: FIFO interrupt 2 tag enable fifo_tag_int2_en 0x00 disable disable tag 0x01 enable enab
Data Sheet BMA456 Page 85 Register (0x4B) AUX_DEV_ID DESCRIPTION: Auxiliary interface slave device id RESET: 0x20 DEFINITION (Go to register map): Name Register (0x4B) AUX_DEV_ID Bit 7 6 Read/Write RW RW Reset Value 0 0 Content i2c_device_addr Bit 3 2 Read/Write RW RW Reset Value 0 0 Content i2c_device_addr i2c_device_addr: I2C device address of Auxiliary slave 5 RW 1 4 RW 0 1 RW 0 0 n/a 0 reserved 5 n/a 0 4 n/a 0 1 RW 1 aux_rd_burst 0 RW 1 Register (0x4C) AUX_IF_CONF DESCRIPTION: Auxiliary inter
Data Sheet BMA456 Page 86 Register (0x4D) AUX_RD_ADDR DESCRIPTION: Auxiliary interface read register address RESET: 0x42 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x4D) AUX_RD_ADDR 7 6 RW RW 0 1 read_addr 3 2 RW RW 0 0 read_addr 5 RW 0 4 RW 0 1 RW 1 0 RW 0 5 RW 0 4 RW 0 1 RW 0 0 RW 0 read_addr: Address to read Register (0x4E) AUX_WR_ADDR DESCRIPTION: Auxiliary interface write register address RESET: 0x4C DEFINITION (Go t
Data Sheet BMA456 Page 87 Register (0x4F) AUX_WR_DATA DESCRIPTION: Auxiliary interface write data RESET: 0x02 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x4F) AUX_WR_DATA 7 6 RW RW 0 0 write_data 3 2 RW RW 0 0 write_data 5 RW 0 4 RW 0 1 RW 1 0 RW 0 write_data: Data to write Register (0x53) INT1_IO_CTRL DESCRIPTION: Configure the electrical behaviour of the interrupt pins RESET: 0x00 DEFINITION (Go to register map): Name Bit R
Data Sheet BMA456 Page 88 od: Configure behaviour of INT1 pin to open drain.
Data Sheet BMA456 Page 89 od: Configure behaviour of INT2 pin to open drain.
Data Sheet BMA456 Page 90 Register (0x56) INT1_MAP DESCRIPTION: Interrupt/Feature mapping on INT1 RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x56) INT1_MAP 7 6 RW RW 0 0 error_int_out any_no_motion_ out 3 2 RW RW 0 0 wrist_tilt_out activity_type_out 5 RW 0 wakeup_out 4 n/a 0 reserved 1 RW 0 step_counter_out 0 n/a 0 reserved step_counter_out: Step-counter watermark or Step-detector output.
Data Sheet BMA456 Page 91 any_no_motion_out: Any-motion/No-motion detection output error_int_out: Error interrupt output Register (0x58) INT_MAP_DATA DESCRIPTION: Interrupt mapping hardware interrupts RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x58) INT_MAP_DATA 7 6 n/a RW 0 0 reserved int2_drdy 3 2 n/a RW 0 0 reserved int1_drdy 5 RW 0 int2_fwm 1 RW 0 int1_fwm 4 RW 0 int2_ffull 0 RW 0 int1_ffull 5 RW 0 4 RW 1 1 RW
Data Sheet BMA456 Page 92 Register (0x5E) FEATURES_IN DESCRIPTION: Feature configuration read/write port RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x5E) FEATURES_IN 7 6 RW RW 0 0 features_in 3 2 RW RW 0 0 features_in 5 RW 0 4 RW 0 1 RW 0 0 RW 0 features_in: Feature configuration read/write data Address Bit Name any_motion 0x5E: settings_1 0x00 10...
Data Sheet BMA456 0x5E: 0x04 0x5E: 0x06 0x5E: 0x08 0x5E: 0x0A 0x5E: 0x0C 0x5E: 0x0E 0x5E: 0x10 0x5E: 0x12 0x5E: 0x14 0x5E: 0x16 0x5E: 0x18 0x5E: 0x1A 0x5E: 0x1C 0x5E: 0x1E 0x5E: 0x20 0x5E: 0x22 0x5E: 0x24 0x5E: 0x26 0x5E: 0x28 0x5E: 0x2A 0x5E: 0x2C 15...0 param_1 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...0 15...
Data Sheet BMA456 0x5E: 0x2E 0x5E: 0x30 0x5E: 0x32 0x5E: 0x34 0x5E: 0x36 settings_22 15...0 param_22 settings_23 15...0 param_23 settings_24 15...0 param_24 settings_25 15...0 param_25 settings_26 9...0 watermark_level 10 reset_counter 11 12 13 en_detector en_counter en_activity tap_doubletap 0x5E: 0x38 0 3...1 wrist_tilt 0x5E: 0x3A settings enable sensitivity 4 single_tap_en 0 settings enable general_settings 0x5E: config_id 0x3C 15...0 identification BST-BMA456-DS000-01 | Version 1.
Data Sheet BMA456 0x5E: 0x3E 1...0 2 4...3 5 7...6 8 axes_remapping map_x_axis Describes axes remapping Map the x axis to desired axis. Value Name Description 0x00 x axis Map to x-axis 0x01 y axis Map to y-axis 0x02 z axis Map to z-axis 0x03 reserved reserved map_x_axis_sign Map the x axis sign to the desired one.
Data Sheet BMA456 Page 96 Register (0x5F) INTERNAL_ERROR DESCRIPTION: Internal error flags RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x5F) INTERNAL_ERROR 7 6 n/a n/a 0 0 reserved 3 2 n/a R 0 0 reserved int_err_2 5 n/a 0 4 n/a 0 1 R 0 int_err_1 0 n/a 0 reserved int_err_1: Internal error flag - long processing time, processing halted int_err_2: Internal error flag - fatal error, processing halted Register (0x6A) NV
Data Sheet BMA456 Page 97 Register (0x6B) IF_CONF DESCRIPTION: Serial interface settings RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x6B) IF_CONF 7 6 n/a n/a 0 0 reserved 3 2 n/a n/a 0 0 reserved 5 n/a 0 1 n/a 0 4 RW 0 if_mode 0 RW 0 spi3 spi3: Configure SPI Interface Mode for primary interface spi3 0x00 spi4 SPI 4-wire mode 0x01 spi3 SPI 3-wire mode if_mode: Auxiliary interface configuration if_mode 0x00 p_auto_s_o
Data Sheet BMA456 Page 98 acc_self_test_en: Enable accelerometer self-test acc_self_test_en 0x00 disabled disabled 0x01 enabled enabled acc_self_test_sign: select sign of self-test excitation as acc_self_test_sign 0x00 negative negative 0x01 positive positive acc_self_test_amp: select amplitude of the selftest deflection: acc_self_test_amp 0x00 low low 0x01 high high Register (0x70) NV_CONF DESCRIPTION: NVM backed configuration bits.
Data Sheet BMA456 Page 99 i2c_wdt_en: I2C Watchdog at the SDI pin in I2C interface mode i2c_wdt_en 0x00 Disable Disable I2C watchdog 0x01 Enable Enable I2C watchdog acc_off_en: Add the offset defined in the off_acc_[xyz] OFFSET register to filtered and unfiltered Accelerometer data acc_off_en 0x00 disabled Disabled 0x01 enabled Enabled Register (0x71) OFFSET_0 DESCRIPTION: Offset compensation for Accelerometer X-axis (NVM backed) RESET: 0x00 DEFINITION (Go to register map): Name Register (0x71) OFFSET_0
Data Sheet BMA456 Page 100 Register (0x73) OFFSET_2 DESCRIPTION: Offset compensation for Accelerometer Z-axis (NVM backed) RESET: 0x00 DEFINITION (Go to register map): Name Register (0x73) OFFSET_2 Bit 7 6 5 Read/Write RW RW RW Reset Value 0 0 0 Content off_acc_z Bit 3 2 1 Read/Write RW RW RW Reset Value 0 0 0 Content off_acc_z off_acc_z: Accelerometer offset compensation (Z-axis).
Data Sheet BMA456 Page 101 Register (0x7D) PWR_CTRL DESCRIPTION: Sensor enable register RESET: 0x00 DEFINITION (Go to register map): Name Bit Read/Write Reset Value Content Bit Read/Write Reset Value Content Register (0x7D) PWR_CTRL 7 6 n/a n/a 0 0 reserved 3 2 n/a RW 0 0 reserved acc_en 5 n/a 0 4 n/a 0 1 n/a 0 reserved 0 RW 0 aux_en 5 RW 0 4 RW 0 1 RW 0 0 RW 0 aux_en 0x00 mag_off Disables the auxiliary sensor. 0x01 mag_on Enables the auxiliary sensor.
Data Sheet BMA456 Page 102 cmd: Available commands (Note: Register will always read as 0x00): cmd 0xa0 nvm_prog Writes the NVM backed registers into NVM 0xb0 fifo_flush Clears all data in the FIFO, does not change FIFO_CONFIG and FIFO_DOWNS registers 0xb6 softreset Triggers a reset, all user configuration settings are overwritten with their default state BST-BMA456-DS000-01 | Version 1.
Data Sheet BMA456 Page 103 6. Digital Interfaces 6.1. Interfaces Beside the standard primary interface (I2C and SPI configurable), where sensor acts as a slave to the application processor, BMA456 supports an auxiliary interface. See picture below. If the auxiliary interface is enabled, the BMA456 can be connected to an external sensor (e.g. a magnetometer) in order to build a 6-DoF solution.
Data Sheet BMA456 Page 104 6.2. Primary Interface By default, the BMA456 operates in I2C mode. The BMA456 interface can also be configured to operate in a SPI 4-wire configuration. It can also be re-configured by software to work in 3-wire mode instead of 4-wire mode. All 3 possible digital interfaces share partly the same pins.
Data Sheet BMA456 Page 105 6.3. Primary Interface I2C/SPI Protocol Selection The protocol is automatically selected based on the chip select CSB pin behavior after power-up. At reset / power-up, BMA456 is in I2C mode. If CSB is connected to VDDIO during power-up and not changed the sensor interface works in I2C mode. For using I2C, it is recommended to hard-wire the CSB line to VDDIO.
Data Sheet BMA456 Page 106 The following figure shows the definition of the SPI timings: tCSB_setup tCSB_hold CSB SCK tSCKL tSCKH SDI SDO tSDI_setup tSDI_hold tSDO_OD SPI timing diagram The SPI interface of the BMA456 is compatible with two modes, ´00´ [CPOL = ´0´ and CPHA = ´0´] and ´11´ [CPOL = ´1´ and CPHA = ´1´]. The automatic selection between ´00´ and ´11´ is controlled based on the value of SCK after a falling edge of CSB.
Data Sheet BMA456 Page 107 CSB SCX X SDX SDO R/W A D6 A D5 A D4 A D3 A D2 A D1 A D0 DI7 X DI6 DI5 DI4 DI3 DI2 DI1 Z logical DI0 X X R/W + register address Data 4-wire basic SPI write sequence (mode ´00´) Multiple write operations are possible by keeping CSB low and continuing the data transfer. Only the first register address has to be written. Addresses are automatically incremented after each write access as long as CSB stays active low.
Data Sheet BMA456 Page 108 CSB SCX 7 X SDX SDO logical R/W A D6 A D5 A D4 A D3 A D2 A D1 A D0 X 6 5 3 2 1 X Z R/W + register address 0 DO7 DO6 DO5 DO4 DO3 DO2 DO1 DO0 Dummy Dummy X Read Data 4-wire basic SPI read sequence (mode ´00´) The data bits are used as follows: R/W: Read/Write bit. When 0, the data SDI is written into the chip. When 1, the data SDO from the chip is read.
Data Sheet BMA456 Page 109 CSB SCK SDI RW AD6 AD5 AD4 AD3 AD2 AD1 AD0 DI7 DI6 DI5 DI4 DI3 DI2 DI1 DI0 3-wire basic SPI read or write sequence (mode ´11´) BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.
Data Sheet BMA456 Page 110 6.5. Primary I2C Interface The I²C bus uses SCL (= SCx pin, serial clock) and SDA (= SDx pin, serial data input and output) signal lines. Both lines are connected to VDDIO externally via pull-up resistors so that they are pulled high when the bus is free. The default I²C address of the device is 0b00011000 (0x18). It is used if the SDO pin is pulled to ´GND´. The alternative address 0b00011001 (0x19) is selected by pulling the SDO pin to ´VDDIO´.
Data Sheet BMA456 Page 111 The figure below shows the definition of the I²C timings given in Table 28: SDA tBUF tf tLOW SCL tHIGH tHDSTA tr tHDDAT tSUDAT SDA tSUSTA tSUSTO I²C timing diagram The I²C protocol works as follows: START: Data transmission on the bus begins with a high to low transition on the SDA line while SCL is held high (start condition (S) indicated by I²C bus master). Once the START signal is transferred by the master, the bus is considered busy.
Data Sheet BMA456 Page 112 I²C write access: I²C write access can be used to write a data byte in one sequence. The sequence begins with start condition generated by the master, followed by 7 bits slave address and a write bit (RW = 0). The slave sends an acknowledge bit (ACKS = 0) and releases the bus. Then the master sends the one byte register address. The slave again acknowledges the transmission and waits for the 8 bits of data which shall be written to the specified register address.
Data Sheet BMA456 Slave I2C ID Start S 0 0 1 1 0 0 0 R/W ACK 0 0 Page 113 Register address (0x12) X 0 0 1 0 0 ACK 1 0 0 Data byte Repeat Start Sr Slave I2C ID 0 0 1 1 0 0 0 R/W ACK 1 0 Data byte Register data - address 0x12 X X X X X X X Register data - address 0x13 ACK X 0 X X X Data byte … X X X X X X X X X X X X X X 0 … 0 X X X X X X X ACK X 0 … Data byte Register data - address 0x16 X X Register data - address 0x15
Data Sheet BMA456 Page 114 6.6. SPI and I²C Access Restrictions In order to allow for the correct internal synchronization of data written to the BMA456, certain access restrictions apply for consecutive write accesses or a write/read sequence through the SPI as well as I2C interface. The required waiting period depends on whether the device is operating in normal mode or other modes.
Data Sheet BMA456 Page 115 7. Pin-out and Connection Diagrams 7.1. Pin-out Top View Bottom View Pads not visible! Pads visible! Pin description Pin# Name I/O Type 1 SDO Digital I/O 2 SDX Digital I/O 3 VDDIO Supply 4 ASDA Digital I/O 5 INT1 Digital I/O 6 INT2 Digital I/O 7 VDD Supply 8 9 10 GNDIO GND CSB Ground Ground Digital in Description Serial data output in SPI Address select in I²C mode see chapter 7.
Data Sheet BMA456 Page 116 7.2. Connection Diagrams without Auxiliary Interface SPI 3-wire SCK SDX 2 VDDIO 3 ASDA 4 ASCL 12 11 10 CSB BMA456 9 GND Top View 8 (Pads not visible!) 100nF 6 7 CS 100nF GNDIO VDD VDD INT2 5 INT1 VDDIO 1 SCX MOSI/ MISO SDO GND INT1 INT2 It is recommended to use 100nF decoupling capacitors at pin 3 (VDDIO) and pin 7 (VDD).
Data Sheet BMA456 Page 117 I2C SCL SDO 1 SDX 2 VDDIO 3 ASDA 4 11 10 CSB BMA456 9 GND Top View 8 (Pads not visible!) 100nF 5 6 INT2 VDDIO 12 INT1 SDA ASCL =1 =0 SCX I2C_ID.0 7 100nF GNDIO VDD VDD GND INT1 INT2 It is recommended to use 100nF decoupling capacitors at pin 3 (VDDIO) and pin 7 (VDD). 7.3.
Data Sheet BMA456 Page 118 4-wire SCK ASDA ASCL 1 MOSI SDX 2 12 11 10 CSB BMA456 9 GND ASDA 4 100nF 5 6 INT2 VDDIO Top View 3 8 (Pads not visible!) INT1 VDDIO ASCL SDO SCX MISO to BMM CS 100nF GNDIO 7 VDD VDD GND INT1 INT2 It is recommended to use 100nF decoupling capacitors at pin 3 (VDDIO) and pin 7 (VDD).
Data Sheet BMA456 Page 119 8. Package 8.1. Package outline dimensions BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice.
Data Sheet BMA456 Page 120 8.2. Sensing axis orientation If the sensor is accelerated in the indicated directions, the corresponding channel will deliver a positive acceleration signal (dynamic acceleration). If the sensor is at rest and the force of gravity is acting along the indicated directions, the output of the corresponding channel will be negative (static acceleration).
Data Sheet BMA456 Page 121 For reference the figure below shows the Android device orientation with an integrated BMA456. BMA456 BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.
Data Sheet BMA456 Page 122 8.3. Landing pattern recommendation The recommended landing pattern for the BMA456 on customer’s PCB is given in the following figure. It is recommended to avoid any wiring underneath the BMA456 (shaded area). BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties.
Data Sheet BMA456 Page 123 8.4. Marking Mass production Labeling CCC Name Symbol Remark Counter ID CCC 3 alphanumeric digits, variable to generate trace-code. Pin 1 identifier top side • -- Name Symbol Remark Eng. sample ID E, N 2 alphanumeric digits, fixed to identify engineering sample, N = “C” Sample ID CC 2 alphanumeric digits, variable to generate trace-code. Pin 1 identifier top side • -- Engineering samples Labeling NCC BST-BMA456-DS000-01 | Version 1.
Data Sheet BMA456 Page 124 8.5.
Data Sheet BMA456 Page 125 8.6. Handling instructions Micromechanical sensors are designed to sense acceleration with high accuracy even at low amplitudes and contain highly sensitive structures inside the sensor element. The MEMS sensor can tolerate mechanical shocks up to several thousand g's. However, these limits might be exceeded in conditions with extreme shock loads such as e.g. hammer blow on or next to the sensor, dropping of the sensor onto hard surfaces etc.
Data Sheet BMA456 Page 126 8.7. Tape and Reel specification BST-BMA456-DS000-01 | Version 1.1 | October 2017 Bosch Sensortec © Bosch Sensortec GmbH reserves all rights even in the event of industrial property rights. We reserve all rights of disposal such as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany. Note: Specifications within this document are subject to change without notice.
Data Sheet BMA456 Page 127 8.8. Environmental safety The BMA456 sensor meets the requirements of the EC restriction of hazardous substances (RoHS) directive, see also: Directive 2011/65/EU of the European Parliament and of the Council of 8 September 2011 on the restriction of the use of certain hazardous substances in electrical and electronic equipment. Halogen content The BMA456 is halogen-free. For more details on the corresponding analysis results please contact your Bosch Sensortec representative.
Data Sheet BMA456 Page 128 9. Legal disclaimer 9.1. Engineering samples Engineering Samples are marked with an asterisk (*) or (e). Samples may vary from the valid technical specifications of the product series contained in this data sheet. They are therefore not intended or fit for resale to third parties or for use in end products. Their sole purpose is internal client testing. The testing of an engineering sample may in no way replace the testing of a product series.
Data Sheet BMA456 Page 129 10.Document history and modification Rev. No Chapter Description of modification/changes Date 1.0 1.1 8.1 Document creation Update 07 Aug 2017 26 Oct 2017 Bosch Sensortec GmbH Gerhard-Kindler-Strasse 9 72770 Reutlingen / Germany contact@bosch-sensortec.com www.bosch-sensortec.com Modifications reserved | Printed in Germany Specifications subject to change without notice Document number: BST-BMA456-DS000-01 Revision_1.1_October_2017 BST-BMA456-DS000-01 | Version 1.
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