BMC150 datasheet(64/142 Pages) BOSCH

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Datasheet

eCompass BMC150

Page 64

BST-BMC150-DS000-04 | Revision 1.0 | July 2014

Bosch Sensortec

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. Not intended for publication.

5.4 FIFO Interrupts

The FIFO controller can generate two different interrupt events, a FIFO-full and a watermark

event. The FIFO-full and watermark interrupts are functional in all FIFO operating modes. The

watermark interrupt is asserted when the fill level in the buffer has reached the frame count

defined by register (0x30) fifo_water_mark_trigger_retain. In order to enable (disable) the

watermark interrupt, the (0x17) int_fwm_en bit must be set to ‘1’ (‘0’). To map the watermark

interrupt signal to INT1 pin (INT2 pin), (0x1A) int1_fwm ((0x1A) int2_fwm) bit must be set to ‘1’.

The status of the watermark interrupt may be read back through the (0x0A) fifo_wm_int bit.

Writing to register (0x30) fifo_water_mark_trigger_retain clears the FIFO buffer.

The FIFO-full interrupt is triggered when the buffer has been completely filled. In FIFO mode

this occurs 32, in STREAM mode 31 samples, and in BYPASS mode 1 sample after the buffer

has been cleared. In order to enable the FIFO-full interrupt, bit (0x17) int_ffull_en as well as one

or both of bits (0x1A) int1_fful or (0x1A) int2_fful must also be set to ‘1’. The status of the FIFO-

full interrupt may be read back through bit (0x0A) fifo_full_int.

BMC150 Datasheet(PDF) 64 Page - Bosch Sensortec GmbH