topic FXLS8471Q - FIFO Fill mode example code in Sensors

FXLS8471Q - FIFO Fill mode example code

andrewneil — Tue, 03 Feb 2026 20:50:17 GMT

here:

https://community.nxp.com/t5/Sensors-Knowledge-Base/FXLS8471Q-FIFO-Fill-mode-example-code/ta-p/1108021

In the first code block, I think the comment against CTRL_REG4 is wrong (or, at least, misleading):

void FXLS8471Q_Init (void) { FXLS8471Q_WriteRegister(CTRL_REG1, 0x00); // Standby mode FXLS8471Q_WriteRegister(F_SETUP_REG, 0xA0); // FIFO Fill mode, 32 samples FXLS8471Q_WriteRegister(CTRL_REG4, 0x40); // Enable FIFO interrupt, push-pull, active low FXLS8471Q_WriteRegister(CTRL_REG5, 0x40); // Route the FIFO interrupt to INT1 - PTA5 FXLS8471Q_WriteRegister(CTRL_REG1, 0x19); // ODR = 100Hz, Active mode }

According to the datasheet, CTRL_REG4 contains only interrupt enable bits - not push-pull or active-low controls.

The push-pull and active-low controls are in CTRL_REG3 (the defaults are push-pull & active-low).

Re: FXLS8471Q - FIFO Fill mode example code

TomasVaverka — Thu, 29 Feb 2024 08:21:45 GMT

Hello Andrew,

Thank you again for your feedback, you are right, both the output mode (push-pull vs. open-drain) and polarity (active low vs. high) are configurable using bits pp_od and ipol in the CTRL_REG3 register.

I have updated the FXLS8471Q_Init function to make this clear.

void FXLS8471Q_Init (void) { FXLS8471Q_WriteRegister(CTRL_REG1, 0x00); // Standby mode FXLS8471Q_WriteRegister(F_SETUP_REG, 0xA0); // FIFO Fill mode, 32 samples FXLS8471Q_WriteRegister(CTRL_REG3, 0x00); // Push-pull, active low interrupt FXLS8471Q_WriteRegister(CTRL_REG4, 0x40); // Enable FIFO interrupt FXLS8471Q_WriteRegister(CTRL_REG5, 0x40); // Route the FIFO interrupt to INT1 - PTA5 FXLS8471Q_WriteRegister(CTRL_REG1, 0x19); // ODR = 100Hz, Active mode }

BR, Tomas

Re: FXLS8471Q - FIFO Fill mode example code

andrewneil — Thu, 29 Feb 2024 10:05:39 GMT

Thanks.

It would be useful to have some samples like this for the FXLS896xAF, please ...