BQ40Z80EVM-020: Timeout/failed to communicate/wrong value

Miles Lin1

Prodigy 40 points

Part Number: BQ40Z80EVM-020

Hi guys,

I am a beginner at bq40z80evm.

I want to do a learning experiment and then connected pack + and pack- to my 308duo charger.

When I press the wake-up button, the 6S battery voltage value is displayed on the screen.

After a while, I find that I can't wake up bq40z80evm anymore(the screen does not show anything).

It is still not able to wake up after removing the charger voltage.

When connecting the computer again, something is not right.

1.No auto-detection is working with bq40z80evm

2.It is not able to communicate(.i.e. failed to communicate or timeout error).

3.wrong value (voltage = 65534 mV current = 8191mA manufacturer Access = 0x6101.....)

Is it the wrong connection to damage it by me?

over 3 years ago

0 Jessica H. over 3 years ago

TI__Genius 11535 points

Hi Miles,

I think what is happening is that the system is going into some safety condition where it is turning off the FETs. This is most likely from the gauge expecting a lower voltage than what the 6s battery is supplying. You can try holding down the wakeup pin and while you are doing that go in and change the cell configuration to 6s.

0 Miles Lin1 over 3 years ago in reply to Jessica H.

Prodigy 40 points

Hi Jessica,

Thanks for your reply.

I hold the wake-up button and open the program.

But there is no data on the Data Memory page so that But I can not change the cell configuration.

0 Jessica H. over 3 years ago in reply to Miles Lin1

TI__Genius 11535 points

Hi Miles,

How did you connect your hardware? Did you change anything between the time it worked and when it wasn't working? Did you follow the steps outlined in the Technical Reference Manual and User's Guide?

0 Miles Lin1 over 3 years ago in reply to Jessica H.

Prodigy 40 points

Hi Jessica,

I have tried to flash firmware after it didn't work.

Now I press the wake-up button and start the application to get a strange device name 0_fffffff_ffffffa5.

It is not able to get data on the data memory page but has responses on the SMB command.

0 Jessica H. over 3 years ago in reply to Miles Lin1

TI__Genius 11535 points

Hi Miles,

Can you first try uploading a new .srec to the gauge? Then try reconnecting you're whole setup and seeing if that helps. If neither of these work, I think you might have damaged the board.

0 Miles Lin1 over 3 years ago in reply to Jessica H.

Prodigy 40 points

Hi Jessica,

Thanks for your help.

I upload firmware again and it works this time.

It looks good now. :)

Power management

Power management forum

BQ40Z80EVM-020: Timeout/failed to communicate/wrong value