Cannot access >=3,3V at GPIOA - STM32F411

[timbo2023]

Dear Ladies and Gentlemen,

for you it is your daily business - for me as customer a contemporary challenge:

Something went wrong with my pin-configuration.

I measure ~1,7 V as GPIO-output of Port A instead of wished >=3.3 V.

My power supply is a USB.

Could you give a sample pin configuration for (3.3 V output) of Port A in discussion?

As additional comment:

Round about 5 V are present at the 5 V-Pin(s).

Thank you in advance.

TIMBO

[AScha.3]

Sooo...

Its about DM422c - right ?

You need anyway just 3 lines : pul, dir, ena. +opto for power.

Set pins as output, open drain . PA8 , 9, 10 . + on opto 5V vom USB port .

(not PA0...123 , they are NOT FT - 5v tolerant !!! ) RTFM !!!!

[timbo2023]

F U I & ((A)nswer) -

my emailaddress is ... xxx

Could you send me this answer in a more common way in german language again?

Thank's a lot ...

sou sou sou - spoken in my time ...

I would like to go on OPTO with an open common PIN as input voltage... but your solution seems to be more comfortable.

[Tesla DeLorean]

>>But I need at least round about 3.6 V ... USB Voltage tap per software possible?

No, there's no magical connectivity here. Go check the schematic, the 5V goes to a 3.3V regulator powering the STM32. The STM32 doesn't have 3.6V available as a High Level

Perhaps you've damaged PA0 ? Pressed the Key, shorting out the MCU?

A photo of the PA0 voltage off the board, and not connected to anything would be more assuring.

Do you have additional BLACK PILL boards you can sanity check against?

https://stm32-base.org/assets/pdf/boards/original-schematic-STM32F411CEU6_WeAct_Black_Pill_V2.0.pdf

Provide schematics of what you've wired, over photos.

GPIOA->OSPEEDR |= 0x00000000; // Doesn't clear bits, basically does nothing

GPIOA->OTYPER |= 0xE; // PA1..3 Open Drain, then external pull-ups to 5V via 10K

A read of the DATA SHEET indicates PA0 is not FT (5V Volt Tolerant), just a standard 3.3V GPIO

https://www.st.com/en/microcontrollers-microprocessors/stm32f411ce.html

[timbo2023]

How I can change the supply regulator?

"If you change the supply regulator to a 3,6v type." @AScha.3

[timbo2023]

Ok - in common I think, that my control voltage is too low. The motor sounds in this way.

In look to the USB voltage, there is no possibility to get this voltage per software?

[timbo2023]

What actually does VB means?

Is it possible to give there a voltage input ~5V on the card?

[Tesla DeLorean]

>>In look to the USB voltage, there is no possibility to get this voltage per software?

How would that even work?

Have you looked at the schematics?

The D+ / D- operate at much lower voltages, and the 5V doesn't get to the STM32F4 MCU

What are you attaching? Link to a manual/datasheet for the stepper controller.

Draw a diagram of what you've connected to what. Is this too much to ask?