GPIO Pin not going High

[jasd33p]

I'm using a Nucleo-H723VG board and trying to use the PB8 and PB9 pins. I'm able to set PB9 high and see a voltage of 3V but for PB8 it only shows a voltage of 359mv. I have tried enabling the internal pullup and still doesn't go high to 3V.

The yellow is PB9, which is going high and blue is PB8, only reads in mv range.

[MM..1]

Are you sure your scope isnt 1:10

[jasd33p]

Yes there 1:1

[MM..1]

Show photo board, i mean ST dont have VG nucleo, but ZG

And 1:1 on display is irelevant, check cable switch

[Andrew Neil]

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@jasd33p wrote:

I'm using a Nucleo-H723VG board

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Have you checked the board User Manual and/or Schematic to see if there's anything else using that pin?

PS

It looks like your scope has a USB socket:

You should be able to use that to download a proper screenshot - which will be much better than a wonky photo with reflections, etc!

[Imen.D]

Hello @jasd33p  

Ensure that there are no conflicts with other peripherals or pin configurations that might be affecting the GPIO pin (check if the pin is also used for another alternate function)

[SofLit]

Hello,

On which connector and which pin you are probing PB8? CN9/11? or CN12/3?

On CN9/11, the solder bridge is not soldered.

[jasd33p]

Sorry meant ZG

[jasd33p]

I was probing PB9 on CN7

[SofLit]

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@jasd33p wrote:

I have tried enabling the internal pullup and still doesn't go high to 3V.

Hope you didn't broke the IO!