AN4506 datasheet(42/47 Pages) STMICROELECTRONICS

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First-in first-out (FIFO) buffer

AN4506

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Figure 25. Stream-to-FIFO mode: interrupt not latched

Figure 26. Stream-to-FIFO mode: interrupt latched

Stream-to-FIFO can be used in order to analyze the sample history that generates an

interrupt; the standard operation is to read FIFO content when FIFO mode is triggered and

FIFO buffer is full and stopped.

6.3.6

Bypass-to-Stream mode

This mode is a combination of the Bypass and Stream modes described above. In Bypass-

to-Stream mode, the FIFO buffer starts operating in Bypass mode and switches to Stream

mode when the selected interrupt occurs.

Follow these steps for Bypass-to-Stream mode configuration:

Configure the desired interrupt generator by using register IG_CFG (0x30).

Turn on FIFO by setting the FIFO_En bit to “1” in the CTRL5 register (0x24). After this

operation the FIFO buffer is enabled but is not collecting data, output registers are

frozen to the last samples set loaded.

Activate Bypass-to-Stream mode by setting the FM[2:0] field to “100” in the

FIFO_CTRL register (0x2E).

AN4506 Datasheet(PDF) 42 Page - STMicroelectronics