How do I turn on GPIO Clock STM32?

How do I turn on GPIO Clock STM32?

STM32 GPIO INPUT Configuration

1. Enable GPIOA clock. The GPIO clock can be enabled in the RCC_AHB1ENR Register.
2. Set the PIN PA1 as Input. To configure the pin as input, we will modify the GPIOx_MODER Register.
3. Configure the Pull UP.
4. Enable the GPIO Clock.
5. Set the Pin as INPUT.
6. Configure the ODR.

Why does GPIO need clock?

1 Answer. The GPIO peripheral is a peripheral just like UART or Timer, it needs a clock to be able to respond to register reads and writes.

What is the configuration of the GPIO pins?

A GPIO pin is a generic pin whose value consists of one of two voltage settings (high or low) and whose behavior can be programmed through software. A GPIO port is a platform-defined grouping of GPIO pins (often 4 or more pins).

What is GPIO speed?

GPIO output speed register means, as the name indicates the configuring speed register and it is only applicable when the GPIO pin is in output mode. GPIO speed register controls the slew rate or the rate at which a signal can change between low/high values (the “rise time” and “fall time”).

What is alternate function STM32?

In addition to acting as General Purpose I/Os, many of the pins on the STM32 microcontrollers have one or more alternate functions. These alternate functions are tied to subsystems inside the MCU, such as one or more SPI, I2C, USART, Timer, DMA or other peripherals.

How do I trigger GPIO?

Use a single GPIO pin to trigger Event Handler Code This resource uses a single GPIO pin to trigger an Event Handler Code task code block. Triggering can either occur at high or low level (no transition required) or at rising or falling edge on the GPIO pin.

What is alternate function mode?

In the alternate function mode, as the name indicates, the pin will be assigned for alternate functionality. The alternate functionality can be anything like UART-TX, UART-RX, timers input channel or ADC’s input channel, etc…

What is alternate function GPIO?

The alternate function is selected by. programming the AFSEL[3:0] bits defined in the Alternate Function Low or High. Register. Alternate functions allow embedded system designers to better tailor the processor chip to the application’s need. Alternate Function Low Register.

How does STM32 GPIO work in input mode?

STM32 GPIO Speed For Input Mode. When a GPIO pin is set to input mode, the data present on the I/O pin is sampled into the Input Data Register every APB2 clock cycle. This means the APB2 bus speed determines the input sampling speed for the GPIO pins. For Output Mode

What’s the maximum current of a GPIO pin?

The maximum current that could be sourced or sunk into any GPIO pin is 25mA as per the datasheet. And you’ve to check it for the specific target microcontroller you’re dealing with. When a GPIO pin is set to input mode, the data present on the I/O pin is sampled into the Input Data Register every APB2 clock cycle.

What is the clock speed of a GPIO?

Mostly they are 3.3v. You’ve to enable the clock for the GPIO you want to use regardless of the mode of operation. When configuring a GPIO output pin, you can select the speed suitable for your application. Whether you need high-frequency switching on the IO line or not.

How to set GPIO pins in analog mode?

Few STM32 GPIO pins can be configured in analog mode which allows the use of ADC, DAC, OPAMP, and COMP internal peripherals. To use a GPIO pin in analog mode, the following register are considered: – GPIOx_MODER to select the mode (Input, Output, Alternate, Analog) – GPIOx_ASCR to select the required function ADC, DAC, OPAMP, or COMP