LIS3DSHTR Datasheet, PDF (20/53 Pages) STMicroelectronics – MEMS digital output motion sensor ultra low-power high performance three-axis “nano” accelerometer

Digital main blocks
5
Digital main blocks
LIS3DSH
5.1
State machine
The LIS3DSH embeds two state machines able to run a user defined program.
The program is made up of a set of instructions that define the transition to successive
states. Conditional branches are possible.
From each state (n) it is possible to have transition to the next state (n+1) or to reset state.
Transition to reset point happens when “RESET condition” is true; Transition to the next step
happens when “NEXT condition” is true.
Interrupt is triggered when output/stop/continue state is reached.
Each state machine allows to implement gesture recognition in a flexible way, free-fall,
wake-up, 4D/6D orientation, pulse counter and step recognition, click/double click,
shake/double shake, face-up/face-down, turn/double turn:
● Code and parameters are loaded by the host into dedicated memory areas for the state
program
● State program with timing based on ODR or decimated time
● Possibility of conditional branches
Table 8. LIS3DSH state machines: sequence of state to execute an algorithm
START
State 1
next
State 2
next
State 3
reset
reset
reset
next
reset
State n
OUTPUT/STOP/CONTINUE
INT set
AM10212V1
20/53
Doc ID 022405 Rev 1