Three TWI (same address slave devices)

[GretaPastore94]

Hi,

I'm trying to receive sensors data from three fdc1004 that have the same address. Can you have three TWI interfaces at the same time? How do you modify the nfr_drv_twi.h to do so? 

Thanks, 

Greta

[Håkon Alseth]

Hi,

I'm trying to receive sensors data from three fdc1004 that have the same address. Can you have three TWI interfaces at the same time? How do you modify the nfr_drv_twi.h to do so? 

No, that will break the purpose of I2C, where the bus fundamentals rely on unique addressing on the bus.

fdc1004

That sensor does not seem to be configurable wrt. I2C-address by looking at the datasheet.

If you are using the nRF52832, you only have two TWI hardware peripherals. What you can do is to:

1. Use a different SCL and SCK for each sensor, and reconfigure the TWI module for every time you poll each sensor.

2. Or use an external mux to select which device to communicate with.

3. Contact the vendor and ask them what their recommendations are wrt. this addressing issue.

Cheers,

Håkon