tcn75a nerves rpi2

[alpa669]

Hi,
i have a system with raspberry 2, nerves and tcn75a but Circuits.I2C.detect_devices() command not return nothing device on i2c bus.
The sensor tcn75a is supported?

Thanks

[fhunleth]

Hi @alpa669,

I haven't used the TCN75A, but I'd expect it to work fine with Nerves. The Circuits.I2C.detect_devices/0 function can't detect all devices so this might be one that doesn't work with it. I looked at the datasheet and didn't see any of the hints that it might not detect, though. Could you double check the wiring and try again? If it still doesn't detect, I'd try reading and writing to it. If it's like the other stealth devices that Circuits.I2C.detect_devices/0 doesn't detect, it will work.

[alpa669]

Hi fhunleth,
thanks for reply. I checked the wiring and the sensor is powered and connected at SCL and SDA of rpi2.

If it's a stealth device how to do discover proper address?
Thanks

[fhunleth]

It would be in the documentation for the board that you have. I'd assume you'd get that from www.microbot.it.

Looking at the TCN75A datasheet, my guess is that it's 0b1001000 (binary), so 0x48 in hex. That's on page 11. The address is settable, though, so www.microbot.it should have the best answer. If it's not 0x48, it will be one of the addresses between 0x49 and 0x4f inclusive.

[alpa669]

I'll try the [0x48..0x4f] address as you suggest.
Thanks