STM32F042F4 datasheet(36/117 Pages) STMICROELECTRONICS

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Pinouts and pin descriptions

STM32F042x4 STM32F042x6

36/117

DocID025832 Rev 5

PB9

I/O

FTf

SPI2_NSS,

I2C1_SDA, IR_OUT,

TIM17_CH1,

EVENTOUT,

CAN_TX

VSS

Ground

VDD

Digital power supply

1. PC13, PC14 and PC15 are supplied through the power switch. Since the switch only sinks a limited amount of current

(3 mA), the use of GPIOs PC13 to PC15 in output mode is limited:

- The speed should not exceed 2 MHz with a maximum load of 30 pF.

- These GPIOs must not be used as current sources (e.g. to drive an LED).

2. After the first RTC domain power-up, PC13, PC14 and PC15 operate as GPIOs. Their function then depends on the

content of the RTC registers which are not reset by the system reset. For details on how to manage these GPIOs, refer to

the RTC domain and RTC register descriptions in the reference manual.

3. Distinct VSSA pin is only available on 48-pin packages. On all other packages, the pin number corresponds to the VSS

pin to which VSSA pad of the silicon die is connected.

4. PA8, PA9, PA10, PA11, PA12, PA13, PA14 and PA15 I/Os are supplied by VDDIO2.

5. Pin pair PA11/12 can be remapped in place of pin pair PA9/10 using SYSCFG_CFGR1 register.

6. After reset, these pins are configured as SWDIO and SWCLK alternate functions, and the internal pull-up on the SWDIO

pin and the internal pull-down on the SWCLK pin are activated.

Table 13. STM32F042x pin definitions (continued)

Pin numbers

Pin name

(function upon

reset)

type

Pin functions

Alternate function

Additional

functions

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