Adding I2C sensor to STEVAL-SMARTAG1

[Zoran Najdovski]

Hi all,

just wondering if it would be possible to add an additional sensor (I2C) on the STEVAL-SMARTAG1 with very thin wires. Would it be possible to hand solder onto the pull-up resistors on the board (R1 and R2)?

cheers,

Zoran

[Rene Lenerve · Accepted solution]

Hi @Zoran Najdovski​ ,

It should be possible in an hardware point of view, take care of I²C address of your new sensor, that it doesn't match the ST25DV address. Pull Up resistor are used for the i²c bus. I²C bus is supplied by VDD_EEPROM controlled by PA15 of the STM32, check that it matches your use case.

From software point of view you will have to modify the embedded software to deal with your new sensor. Another point to consider is that three sensors are using dedicated gpio pins to wake up MCU. If you would like this feature you'll need to connect an IRQ pin to one of this three GPIO (but risk of irq conflict) or to solder on a new GPIO (need to configure this new GPIO).

Maybe something else I missed too...

Hope this can help you,

Regards.