Specifications

BMA180
Preliminary data sheet
Bosch Sensortec
Rev. 1.0 Page 28 / - proprietary information - 06 March 2009
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as copying and passing on to third parties. BOSCH and the symbol are registered trademarks of Robert Bosch GmbH, Germany.
Specifications within this document are preliminary and subject to change without notice. Document is not intended for publication.
As EEPROM reading, EEPROM writing is also an indirect procedure. Data from corresponding
image registers are written to EEPROM after sending write transaction to addresses 40h to 5Fh.
As EEPROM word is 16-bit (and writing is done in parallel), transaction with even address writes
to this address (A) and one address above (A+1). The transaction with odd address is ignored.
Data of writing transition is ignored (SPI) or can be omitted (I2C).
Example:
SPI writing to address 50h starts writing operation (register 30h to EEPROM 50h, register 31h to
EEPROM 51h).
EEPROM write operation shouldn’t occur when an update_image is ongoing (EEPROM is in
read mode at this moment). This means EEPROM write is forbidden also during 10 ms after
power ON reset, after soft_reset and after update_image is written to 1. EEPROM write is also
forbidden during sleep mode and for 10 ms after removal of sleep mode.
EEPROM write operation could render ADC conversion results unusable, thus a soft-reset after
EEPROM write is necessary.
7.5.4 EEPROM protection
The EEPROM bytes between addresses 5Ch to 5Fh are protected in write mode because it
contains Bosch Sensortec proprietary information and settings. It also contains the ee_w_flag
which can be used to detect if any EEPROM write sequence occurred after final test (i.e. if the
customer wrote anything into the non-protected EEPROM). Customer is not able to write the
ee_w_flag.
Also the image registers corresponding to the locked EEPROM area are locked by the
EEPROM lock mechanism in order to avoid mal-functions on the overall system.
7.5.5 EEPROM content upon delivery (after production test)
1. CRC: CRC code may be used to verify whether a calibration was done after Bosch
production test
2. CD1, CD2: content may differ for each IC, since these bytes can be used by customer to
store any data in the non-volatile memory. Its content does not influence the ASIC
functionality.
3. Analog trimming bits (addresses 5Bh to 5Eh): Content may differ for each IC.
4. Calibration data: These data and its default values are summarized in the following table.