STM32G070RBT6 with external pull-up resistor having weird voltage level

[AAApink]

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我在使用STM32G070系列芯片时，外部电阻上拉到3.3V，接入STM32芯片后测量，发现GPIOA 15 和GPIO A8两个引脚是0.9V的电压，为什么？

Translation:

"When using the STM32G070 series chip, I pulled the external resistor up to 3.3V. After connecting it to the STM32 chip, I measured the voltage on the GPIOA 15 and GPIO A8 pins and found that they were 0.9V. Why is that?"

[KDJEM.1]

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The language of this community is English, please look at How to write your question to maximize your chance... - STMicroelectronics Community.

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@AAApink wrote:

我在使用STM32G070系列芯片时，外部电阻上拉到3.3V，接入STM32芯片后测量，发现GPIOA 15 和GPIO A8两个引脚是0.9V的电压，为什么？

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Translation: "When using the STM32G070 series chip, I pulled the external resistor up to 3.3V. After connecting it to the STM32 chip, I measured the voltage on the GPIOA 15 and GPIO A8 pins and found that they were 0.9V. Why is that?"

PA15 or PB15?

For PA8 pin, upon reset, a pull-down resistor might be present on PA8, PB15, PD0, or PD2, depending on the voltage level on PA9/PC6, PA10/PB0, PD1, and PD3, respectively. In order to disable this resistor, strobe the UCPDx_STROBE bit of the SYSCFG_CFGR1 register during start-up sequence, please look at Datasheet - STM32G070CB/KB/RB - Arm<Sup>® </Sup>Cortex<Sup>®</Sup>-M0+ 32-bit MCU, 128 KB Flash, 36 KB RAM, 4x USART, timers, ADC, comm. I/Fs, 2.0-3.6 V.

Thank you.

Kaouthar