BQ40Z80: bq40z80 LED display with pin 15

Shane Ke

Part Number: BQ40Z80
Other Parts Discussed in Thread: BQSTUDIO

Hi,

We would like to set LED display control pin to pin 15.

However, when I set MFP15_sel1.0 to 0x01 and then do reset, I don’t see the pin 15 pull hig. ( I also set MSF13_sel2.0 to unused 0x1xx)

Do I misunderstand or loss something?

over 7 years ago

0 Steve Schnier over 7 years ago

TI__Expert 4645 points

If you are using the EVM, please check that you have the board set up without any conflicts. The default for pin 15 is VC7EN, so you have to be using a 6S or less cell configuration if you change the function to /DISP. You will also want to change the function of pin 12, as that is also used for a 7S configuration. To support less than 7S, you will also need to change the cell configuration register in the Data Memory section, under Settings.

0 Shane Ke over 7 years ago in reply to Steve Schnier

Intellectual 255 points

Hi Steve,

Thanks for help.

0 Mictronics over 6 years ago in reply to Shane Ke

Prodigy 150 points

Shane, did you manage to get pin 15 working? Can you provide me a configuration of your pins and LEDs?

My entire pack with bq40z80 is working, except the display button on pin 15 will not trigger any LED activity. They work only when triggered through BQStudio commands or when LEDCHG is set while charging.

Attached my pin and LED configuration. Cell configuration is set to 6S.

0 Steve Schnier over 6 years ago in reply to Mictronics

TI__Expert 4645 points

Just a quick thought - did you configure the jumpers on the board to route the switch (S3) to pin 15? This is detailed in the bq40z80 EVM User guide, and it should be J6[2,3] and J8[1,2].

0 Mictronics over 6 years ago in reply to Steve Schnier

Prodigy 150 points

Steve, it's a custom board design. Display button is directly connected to pin 15, other end to VSS. I see the pin is pulled high and goes low when I press the button. So I believe it is configured correct.

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BQ40Z80: bq40z80 LED display with pin 15