Table of Contents
What is GPIO output level STM32?
GPIO output level: this means, after initialization, the pin will state in logic level high or low( output voltage 3.3V or 0V). For example, if the pin is pulled-up, the logic level 0 will be 3.3V and logic level 1 will be 0V. It is applied the other way around for pulled-down.
What is GPIO speed in STM32?
The STM32F103C8 runs at a maximum clock speed of 72 MHz. So 36 MHz is the maximum frequency that can be generated on a GPIO as a separate clock cycle is needed to set and clear the pin.
What is GPIO Alternate Function Mode?
When a GPIO pin is used for any alternate purpose other than as a general purpose input or output pin, then it is said to be in alternate function mode. Again, this can be when you need any of these pins to function as timer pins or pins for the I2C protocol or the SPI protocol or the UART or CAN protocol.
What is GPIO STM32?
The STM32 microcontroller general-purpose input/output pin (GPIO) provides many ways to interface with external circuits within an application framework. This application note must be used in conjunction with the related STM32 reference manual and datasheet available at www.st.com.
What is open drain in STM32?
Open-drain output configuration is nothing but the top PMOS transistor is deactivated as shown in Figure1. When the transistor is ON, the pin pulled to the ground. When the transistor is OFF, the drain of the transistor will be floating or open. That’s the reason it is called an open drain.
What is push-pull pin?
A push-pull GPIO has the ability to both source and sink current. With a push-pull GPIO, a transistor connects to VCC or GND to drive a signal high or low. When the output goes low, the signal is actively “pulled” to ground, and when the output goes high it is actively “pushed” to VCC.
What is GPIO interface?
GPIO stands for General Purpose Input/Output. It’s a standard interface used to connect microcontrollers to other electronic devices. For example, it can be used with sensors, diodes, displays, and System-on-Chip modules.
What is GPIO output 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. If you select GPIO pin as low speed, that is if the speed register is 00, then the maximum achievable switching frequency of that GPIO pin will be 8MHz.
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.
What is af STM32?
The GPIO peripheral is used to configure the device IO ports, also called pins or pads. Alternate function (AF) links allow to connect the IO port to an internal peripheral digital line.
What is open drain pin?
An open-drain or open-collector output pin is driven by a single transistor, which pulls the pin to only one voltage (generally, to ground). When the output device is off, the pin is left floating (open, or hi-z).
What is open drain configuration?
What is an Open Drain : Configuration & Its Working. An open-drain or open-collector output pin is simply a transistor that is connected to the ground. Whenever we apply high input at the gate, drain, and source are shorted. Whenever we apply low input at the gate, drain, and source are disconnected.
Which STM32 GPIO pins can be configured 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
What are the I/O pins on the STM32?
Toggling I/O pins on STM32 07 Dec 2018# stm32f407gpio: jeeh All microcontrollers have I/O pins to connect to the outside world. These can be used as inputs or outputs, and tend to have various interesting capabilities. Here, I’ll treat these “General Purpose I/O” pins as outputs and try to toggle them as quickly as possible.
What is the STM32 tutorial series about?
This is the Series of tutorials on STM32 Microcontroller. The aim of this series is to provide easy and practical examples that anyone can understand. Basically, you can write GPIO codes in multiple ways (Using HAL, GPIO driver).
How to set the output mode of a GPIO port?
Each port has several registers, to set its pin modes and to get / set the current pin state. The output mode is set in the “GPIO port mode register” (MODER) at offset 0x0, with 2 configuration bits per pin. For pin 13, bit positions 27..26 will need to be set to binary “01” (0b01), as follows: