BQ40Z80: BQ40Z80

Randy Larimer

Part Number: BQ40Z80

Tool/software:

When using the BQ40Z80 and polling devices on our I2C bus we get the device address 37 as an active address along with the BQ40Z80 device address with nothing else on the I2C bus. Is this address used in the BQ40Z80?

6 months ago

0 Alan Frias 6 months ago

TI__Mastermind 25165 points

Hello Randy,

Below I attached what 0x0037 is on the address bus along with the link to where I located it. But it appears to be that 0x0037 is a manufacturereAccess() and this could explain it being the only thing on the I2C bus.

Look into page 120 for 0x0037 information:
https://www.ti.com/lit/ug/sluubt5c/sluubt5c.pdf?ts=1739393172600&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FBQ40Z80

Regards,
Alan

0 Randy Larimer 6 months ago in reply to Alan Frias

Prodigy 30 points

We were able to capture the response to i2cdetect from the device at address0x37- there is definitely something there, its not just noise. Trying to read it like an eeprom, but just get FFs. We are using an 8 channel i2c mux between multiple bq40Z80s.The screen shots below show there is a call to the i2c mux between every address that it is scanning. Is this truly the authentication key?