GPIO_D pin 9 remains ''high''

[con3]

Posted on April 05, 2018 at 03:06

Hey everyone,

I'm using a nucleo f722ze which has an onboard stm32f722ze.

The problem:

GPIO_D pin 9 remains above 1.5 V even when it's set as off(''reset state''). Every other pin I've used and tested doesn't resemble this behavior. They go straight down to 0V.

Image of me toggling this pin:

What I've done:

I've literally generated a blank project and this pin still stays at 1.5V, I've tried initializing the pin and forcing it to the reset state, but still it stays at 1.5V.

I'm not sure if I'm overlooking something, what could be causing this?

Thanks in advance for any help!

gpio-init reset-pin stmcube-gpio gpio-pin-configuration

[Tesla DeLorean · Accepted solution]

Posted on April 05, 2018 at 04:30

PD9 (USART3_RX) is driven by the ST-LINK VCP

http://www.st.com/content/ccc/resource/technical/document/user_manual/group0/26/49/90/2e/33/0d/4a/da/DM00244518/files/DM00244518.pdf/jcr:content/translations/en.DM00244518.pdf

 

[con3]

Posted on April 05, 2018 at 04:34

Hi Clive, Thank you for the reply.

Should it still be an issue even if I don't have the stlink coupled and don't have PD9 setup as usart3_rx?

Cause even in this case it remains high

[Tesla DeLorean]

Posted on April 05, 2018 at 04:59

Your configuration of the pin has little bearing on what's been driven from the other end. Remove the solder bridge (SB6) that connects it to the STM32F103 part

[con3]

Posted on April 05, 2018 at 11:16

Thank you Clive, I completely understand