GPIO Driver

Overview

The MCUXpresso SDK provides a peripheral driver for the General-Purpose Input/Output (GPIO) module of MCUXpresso SDK devices.

Typical use case

Output Operation

/* Output pin configuration */
gpio_pin_config_t led_config =
{
    kGpioDigitalOutput,
    1,
};
/*  Sets the configuration */
GPIO_PinInit(GPIO_LED, LED_PINNUM, &led_config);

Input Operation

/*  Input pin configuration */
PORT_SetPinInterruptConfig(BOARD_SW2_PORT, BOARD_SW2_GPIO_PIN, kPORT_InterruptFallingEdge);
NVIC_EnableIRQ(BOARD_SW2_IRQ);
gpio_pin_config_t sw1_config =
{
    kGpioDigitalInput,
    0,
};
/* Sets the input pin configuration */
GPIO_PinInit(GPIO_SW1, SW1_PINNUM, &sw1_config);

GPIO Configuration
void	GPIO_PinInit (GPIO_Type *base, uint32_t pin, const gpio_pin_config_t *config)
	Initializes a GPIO pin used by the board. More...

GPIO Output Operations
static void	GPIO_WritePinOutput (GPIO_Type *base, uint32_t pin, uint8_t output)
	Sets the output level of the multiple GPIO pins to the logic 1 or 0. More...
static void	GPIO_SetPinsOutput (GPIO_Type *base, uint32_t mask)
	Sets the output level of the multiple GPIO pins to the logic 1. More...
static void	GPIO_ClearPinsOutput (GPIO_Type *base, uint32_t mask)
	Sets the output level of the multiple GPIO pins to the logic 0. More...
static void	GPIO_TogglePinsOutput (GPIO_Type *base, uint32_t mask)
	Reverses the current output logic of the multiple GPIO pins. More...

GPIO Input Operations
static uint32_t	GPIO_ReadPinInput (GPIO_Type *base, uint32_t pin)
	Reads the current input value of the GPIO port. More...

GPIO Interrupt
uint32_t	GPIO_GetPinsInterruptFlags (GPIO_Type *base)
	Reads the GPIO port interrupt status flag. More...
void	GPIO_ClearPinsInterruptFlags (GPIO_Type *base, uint32_t mask)
	Clears multiple GPIO pin interrupt status flags. More...
void	GPIO_CheckAttributeBytes (GPIO_Type *base, gpio_checker_attribute_t attribute)
	The GPIO module supports a device-specific number of data ports, organized as 32-bit words. More...

Function Documentation

void GPIO_PinInit	(	GPIO_Type *	base,
		uint32_t	pin,
		const gpio_pin_config_t *	config
	)

To initialize the GPIO, define a pin configuration, as either input or output, in the user file. Then, call the GPIO_PinInit() function.

This is an example to define an input pin or an output pin configuration.

* // Define a digital input pin configuration,
* gpio_pin_config_t config =
* {
*   kGPIO_DigitalInput,
*   0,
* }
* //Define a digital output pin configuration,
* gpio_pin_config_t config =
* {
*   kGPIO_DigitalOutput,
*   0,
* }
* 

Parameters

base	GPIO peripheral base pointer (GPIOA, GPIOB, GPIOC, and so on.)
pin	GPIO port pin number
config	GPIO pin configuration pointer

static void GPIO_WritePinOutput ( GPIO_Type *  base, uint32_t  pin, uint8_t  output  )

inlinestatic

Parameters

base	GPIO peripheral base pointer (GPIOA, GPIOB, GPIOC, and so on.)
pin	GPIO pin number
output	GPIO pin output logic level. 0: corresponding pin output low-logic level. 1: corresponding pin output high-logic level.

static void GPIO_SetPinsOutput ( GPIO_Type *  base, uint32_t  mask  )

inlinestatic

Parameters

base	GPIO peripheral base pointer (GPIOA, GPIOB, GPIOC, and so on.)
mask	GPIO pin number macro

static void GPIO_ClearPinsOutput ( GPIO_Type *  base, uint32_t  mask  )

inlinestatic

Parameters

base	GPIO peripheral base pointer (GPIOA, GPIOB, GPIOC, and so on.)
mask	GPIO pin number macro

static void GPIO_TogglePinsOutput ( GPIO_Type *  base, uint32_t  mask  )

inlinestatic

Parameters

base	GPIO peripheral base pointer (GPIOA, GPIOB, GPIOC, and so on.)
mask	GPIO pin number macro

static uint32_t GPIO_ReadPinInput ( GPIO_Type *  base, uint32_t  pin  )

inlinestatic

Parameters

base	GPIO peripheral base pointer (GPIOA, GPIOB, GPIOC, and so on.)
pin	GPIO pin number

Return values

GPIO	port input value 0: corresponding pin input low-logic level. 1: corresponding pin input high-logic level.

uint32_t GPIO_GetPinsInterruptFlags

(

GPIO_Type *

base

)

If a pin is configured to generate the DMA request, the corresponding flag is cleared automatically at the completion of the requested DMA transfer. Otherwise, the flag remains set until a logic one is written to that flag. If configured for a level sensitive interrupt that remains asserted, the flag is set again immediately.

Parameters

base	GPIO peripheral base pointer (GPIOA, GPIOB, GPIOC, and so on.)

Return values

The	current GPIO port interrupt status flag, for example, 0x00010001 means the pin 0 and 17 have the interrupt.

void GPIO_ClearPinsInterruptFlags	(	GPIO_Type *	base,
		uint32_t	mask
	)

Parameters

base	GPIO peripheral base pointer (GPIOA, GPIOB, GPIOC, and so on.)
mask	GPIO pin number macro

void GPIO_CheckAttributeBytes	(	GPIO_Type *	base,
		gpio_checker_attribute_t	attribute
	)

Each 32-bit data port includes a GACR register, which defines the byte-level attributes required for a successful access to the GPIO programming model. The attribute controls for the 4 data bytes in the GACR follow a standard little endian data convention.

Parameters

base	GPIO peripheral base pointer (GPIOA, GPIOB, GPIOC, and so on.)
mask	GPIO pin number macro