Mismatch of I2C addresses between Logic Analyzer and i2c_scanner

I have an Arduino nano connected to a RTC DS3231 via I2C that works as expected when using the respective Example sketch.

The problem comes when I try the i2c_scanner sketch to get the addresses, the i2c_scanner gives me this two addresses as:

Scanning...
I2C device found at address 0x57  !
I2C device found at address 0x68  !
done

While the Logic Analyzer gives me these ones instead:

Time [s], Analyzer Name, Decoded Protocol Result
0.010747500000000,I2C,Setup Write to [0xAE] + ACK
0.013231875000000,I2C,Setup Write to [0xD0] + ACK

As you can confirm in the pictures attached… Why is this happening?

Serial_i2c.PNG

Because the I2C address normally used is the first 7 bits of the address byte. The low bit specifies if it's a read or write operation (so writing to I2C address 0x68 would mean the first byte was either D0 or D1). I

See I²C - Wikipedia or the diagrams in your nicer I2C device datasheets.

DrAzzy:
Because the I2C address normally used is the first 7 bits of the address byte. The low bit specifies if it’s a read or write operation (so writing to I2C address 0x68 would mean the first byte was either D0 or D1). I

Yep, is that the cause. I change the Analyzer Settings from 8-bit read/write bit included to 7-bit address bits only and I got the correct address as shown in the picture.

I’m surprised that Saleae doesn’t make the 7-bit option the default one!

Thanks for your answer.