General-Purpose IO Configuration Functions

Typedefs
typedef enum ALT_GPIO_PIN_DIR_e	ALT_GPIO_PIN_DIR_t
typedef enum ALT_GPIO_PIN_TYPE_e	ALT_GPIO_PIN_TYPE_t
typedef enum ALT_GPIO_PIN_POL_e	ALT_GPIO_PIN_POL_t
typedef enum ALT_GPIO_PIN_DEBOUNCE_e	ALT_GPIO_PIN_DEBOUNCE_t
typedef enum ALT_GPIO_PIN_SYNC_e	ALT_GPIO_PIN_SYNC_t
typedef enum ALT_GPIO_PIN_DATA_e	ALT_GPIO_PIN_DATA_t
typedef enum ALT_GPIO_PORT_e	ALT_GPIO_PORT_t
typedef enum ALT_GPIO_PORTBIT_e	ALT_GPIO_PORTBIT_t

Enumerations
enum	ALT_GPIO_PIN_DIR_e { ALT_GPIO_PIN_INPUT , ALT_GPIO_PIN_OUTPUT }
enum	ALT_GPIO_PIN_TYPE_e { ALT_GPIO_PIN_LEVEL_TRIG_INT , ALT_GPIO_PIN_EDGE_TRIG_INT }
enum	ALT_GPIO_PIN_POL_e { ALT_GPIO_PIN_ACTIVE_LOW , ALT_GPIO_PIN_ACTIVE_HIGH }
enum	ALT_GPIO_PIN_DEBOUNCE_e { ALT_GPIO_PIN_NODEBOUNCE , ALT_GPIO_PIN_DEBOUNCE }
enum	ALT_GPIO_PIN_SYNC_e { ALT_GPIO_PIN_NOSYNC , ALT_GPIO_PIN_SYNC }
enum	ALT_GPIO_PIN_DATA_e { ALT_GPIO_PIN_DATAZERO , ALT_GPIO_PIN_DATAONE }
enum	ALT_GPIO_PORT_e { ALT_GPIO_PORTA , ALT_GPIO_PORTB , ALT_GPIO_PORTC , ALT_GPIO_PORT_UNKNOWN }
enum	ALT_GPIO_PORTBIT_e {   ALT_GPIO_BIT0 = ALT_TWO_TO_POW0 , ALT_GPIO_BIT1 = ALT_TWO_TO_POW1 , ALT_GPIO_BIT2 = ALT_TWO_TO_POW2 , ALT_GPIO_BIT3 = ALT_TWO_TO_POW3 ,   ALT_GPIO_BIT4 = ALT_TWO_TO_POW4 , ALT_GPIO_BIT5 = ALT_TWO_TO_POW5 , ALT_GPIO_BIT6 = ALT_TWO_TO_POW6 , ALT_GPIO_BIT7 = ALT_TWO_TO_POW7 ,   ALT_GPIO_BIT8 = ALT_TWO_TO_POW8 , ALT_GPIO_BIT9 = ALT_TWO_TO_POW9 , ALT_GPIO_BIT10 = ALT_TWO_TO_POW10 , ALT_GPIO_BIT11 = ALT_TWO_TO_POW11 ,   ALT_GPIO_BIT12 = ALT_TWO_TO_POW12 , ALT_GPIO_BIT13 = ALT_TWO_TO_POW13 , ALT_GPIO_BIT14 = ALT_TWO_TO_POW14 , ALT_GPIO_BIT15 = ALT_TWO_TO_POW15 ,   ALT_GPIO_BIT16 = ALT_TWO_TO_POW16 , ALT_GPIO_BIT17 = ALT_TWO_TO_POW17 , ALT_GPIO_BIT18 = ALT_TWO_TO_POW18 , ALT_GPIO_BIT19 = ALT_TWO_TO_POW19 ,   ALT_GPIO_BIT20 = ALT_TWO_TO_POW20 , ALT_GPIO_BIT21 = ALT_TWO_TO_POW21 , ALT_GPIO_BIT22 = ALT_TWO_TO_POW22 , ALT_GPIO_BIT23 = ALT_TWO_TO_POW23 ,   ALT_GPIO_BIT24 = ALT_TWO_TO_POW24 , ALT_GPIO_BIT25 = ALT_TWO_TO_POW25 , ALT_GPIO_BIT26 = ALT_TWO_TO_POW26 , ALT_GPIO_BIT27 = ALT_TWO_TO_POW27 ,   ALT_GPIO_BIT28 = ALT_TWO_TO_POW28 , ALT_GPIO_BIT29 = ALT_TWO_TO_POW29 , ALT_GPIO_BIT30 = ALT_TWO_TO_POW30 , ALT_GPIO_BIT31 = (int32_t) (1UL<<31) ,   ALT_GPIO_BITNUM_MAX = (28) , ALT_GPIO_BIT_MAX = (1 << ALT_GPIO_BITNUM_MAX) , ALT_END_OF_GPIO_PORT_SIGNALS = (32) }

Functions
ALT_STATUS_CODE	alt_gpio_init (void)
ALT_STATUS_CODE	alt_gpio_uninit (void)
ALT_STATUS_CODE	alt_gpio_port_datadir_set (ALT_GPIO_PORT_t gpio_pid, uint32_t mask, uint32_t config)
uint32_t	alt_gpio_port_datadir_get (ALT_GPIO_PORT_t gpio_pid, uint32_t mask)
ALT_STATUS_CODE	alt_gpio_port_data_write (ALT_GPIO_PORT_t gpio_pid, uint32_t mask, uint32_t val)
uint32_t	alt_gpio_port_data_read (ALT_GPIO_PORT_t gpio_pid, uint32_t mask)
ALT_STATUS_CODE	alt_gpio_port_debounce_set (ALT_GPIO_PORT_t gpio_pid, uint32_t mask, uint32_t config)
uint32_t	alt_gpio_port_debounce_get (ALT_GPIO_PORT_t gpio_pid, uint32_t mask)
ALT_STATUS_CODE	alt_gpio_port_sync_set (ALT_GPIO_PORT_t gpio_pid, uint32_t config)
ALT_STATUS_CODE	alt_gpio_port_sync_get (ALT_GPIO_PORT_t gpio_pid)
ALT_STATUS_CODE	alt_gpio_port_config (ALT_GPIO_PORT_t gpio_pid, uint32_t mask, ALT_GPIO_PIN_DIR_t dir, ALT_GPIO_PIN_TYPE_t type, ALT_GPIO_PIN_POL_t pol, ALT_GPIO_PIN_DEBOUNCE_t debounc, uint32_t data)

Detailed Description

This functional group contains functions to control, configure and manage the general-purpose IO signals as individual signals or as groups of signals. This group of functions can operate on multiple bits within the same GPIO port and accepts a bit mask to specify which bits an operation will operate on. Other bits within the same GPIO port are not changed.

This example shows how multiple drivers or applications can use this feature to easily prevent conflict while accessing the same GPIO port:

#define DRIVER_0_GPIO_MSK   0x0010FF03;
#define DRIVER_1_GPIO_MSK   0x002000F8;
#define DRIVER_2_GPIO_MSK   0x03C00004;
#define DRIVER_3_GPIO_MSK   0x000F0000;

   alt_gpio_port_data_write(ALT_GPIO_PORTA, DRIVER_0_GPIO_MSK, init_val0);
   alt_gpio_port_data_write(ALT_GPIO_PORTA, DRIVER_1_GPIO_MSK, init_val1);
   alt_gpio_port_data_write(ALT_GPIO_PORTA, DRIVER_2_GPIO_MSK, init_val2);
   alt_gpio_port_data_write(ALT_GPIO_PORTA, DRIVER_3_GPIO_MSK, init_val3);
   alt_gpio_port_int_type_set(ALT_GPIO_PORTA, DRIVER_1_GPIO_MSK, config_val1);

Typedef Documentation

ALT_GPIO_PIN_DATA_t

typedef enum ALT_GPIO_PIN_DATA_e ALT_GPIO_PIN_DATA_t

This type definition enumerates the possible data states of the GPIO bits.

ALT_GPIO_PIN_DEBOUNCE_t

typedef enum ALT_GPIO_PIN_DEBOUNCE_e ALT_GPIO_PIN_DEBOUNCE_t

This type definition enumerates whether or not the debounce metastability flip-flops are inserted or not. These are used to debounce signals presented to the GPIO inputs. A signal must be steady for two periods of the gpio_db_clk clock before it is considered valid. The frequency of the gpio_db_clk clock may be set using the Clock Manager API.

ALT_GPIO_PIN_DIR_t

typedef enum ALT_GPIO_PIN_DIR_e ALT_GPIO_PIN_DIR_t

This type definition enumerates the data direction (input or output) of the GPIO signals.

ALT_GPIO_PIN_POL_t

typedef enum ALT_GPIO_PIN_POL_e ALT_GPIO_PIN_POL_t

This type definition enumerates the polarity of the interrupt sources (falling-edge or rising-edge for edge-triggered interrupts, active-low or active-high for level-triggered interrupts) of the GPIO signals.

ALT_GPIO_PIN_SYNC_t

typedef enum ALT_GPIO_PIN_SYNC_e ALT_GPIO_PIN_SYNC_t

This type definition enumerates whether or not level-sensitive interrupts are synchronized to the internal pclk_intr clock. It has no effect for GPIO signals that are selected as outputs, or if the interrupt is not enabled, or if the interrupt is set to be edge-triggered. This is a port-wide option.

ALT_GPIO_PIN_TYPE_t

typedef enum ALT_GPIO_PIN_TYPE_e ALT_GPIO_PIN_TYPE_t

This type definition enumerates the type of interrupt source (level-triggered or edge-triggered) of the GPIO signals.

ALT_GPIO_PORT_t

typedef enum ALT_GPIO_PORT_e ALT_GPIO_PORT_t

This type definition enumerates the GPIO ports that the GPIO manager handles.

ALT_GPIO_PORTBIT_t

typedef enum ALT_GPIO_PORTBIT_e ALT_GPIO_PORTBIT_t

This type definition enumerates the individual bits within the GPIO ports used by the GPIO manager. The bit-ordering must match the hardware bit-ordering. Since the ordering and packing of bitfields is not standardized in C/C++, the following are defined as masks.
For example, to set bits 3 and 4 of GPIO port B outputs (assuming the bits had previously been set to outputs), the user could use the syntax:

alt_gpio_port_data_write(ALT_GPIO_PORTB, ALT_GPIO_BIT3 | ALT_GPIO_BIT4);

Enumeration Type Documentation

ALT_GPIO_PIN_DATA_e

enum ALT_GPIO_PIN_DATA_e

This type definition enumerates the possible data states of the GPIO bits.

Enumerator
ALT_GPIO_PIN_DATAZERO
ALT_GPIO_PIN_DATAONE

ALT_GPIO_PIN_DEBOUNCE_e

enum ALT_GPIO_PIN_DEBOUNCE_e

This type definition enumerates whether or not the debounce metastability flip-flops are inserted or not. These are used to debounce signals presented to the GPIO inputs. A signal must be steady for two periods of the gpio_db_clk clock before it is considered valid. The frequency of the gpio_db_clk clock may be set using the Clock Manager API.

Enumerator
ALT_GPIO_PIN_NODEBOUNCE
ALT_GPIO_PIN_DEBOUNCE

ALT_GPIO_PIN_DIR_e

enum ALT_GPIO_PIN_DIR_e

This type definition enumerates the data direction (input or output) of the GPIO signals.

Enumerator
ALT_GPIO_PIN_INPUT
ALT_GPIO_PIN_OUTPUT

ALT_GPIO_PIN_POL_e

enum ALT_GPIO_PIN_POL_e

This type definition enumerates the polarity of the interrupt sources (falling-edge or rising-edge for edge-triggered interrupts, active-low or active-high for level-triggered interrupts) of the GPIO signals.

Enumerator
ALT_GPIO_PIN_ACTIVE_LOW	Indicates active-low for level-triggered interrupts and falling-edge for edge-triggered interrupts
ALT_GPIO_PIN_ACTIVE_HIGH	Indicates active-high for level-triggered interrupts and rising-edge for edge-triggered interrupt

ALT_GPIO_PIN_SYNC_e

enum ALT_GPIO_PIN_SYNC_e

This type definition enumerates whether or not level-sensitive interrupts are synchronized to the internal pclk_intr clock. It has no effect for GPIO signals that are selected as outputs, or if the interrupt is not enabled, or if the interrupt is set to be edge-triggered. This is a port-wide option.

Enumerator
ALT_GPIO_PIN_NOSYNC
ALT_GPIO_PIN_SYNC

ALT_GPIO_PIN_TYPE_e

enum ALT_GPIO_PIN_TYPE_e

This type definition enumerates the type of interrupt source (level-triggered or edge-triggered) of the GPIO signals.

Enumerator
ALT_GPIO_PIN_LEVEL_TRIG_INT
ALT_GPIO_PIN_EDGE_TRIG_INT

ALT_GPIO_PORT_e

enum ALT_GPIO_PORT_e

This type definition enumerates the GPIO ports that the GPIO manager handles.

Enumerator
ALT_GPIO_PORTA	Port A - 29-bit GPIO port A.
ALT_GPIO_PORTB	Port B - 29-bit GPIO port B.
ALT_GPIO_PORTC	Port C - 29-bit GPIO port C. 13 bits are used for GPIO signals, 14 bits are used for GPI-only signals that are shared with the DDR interface, 2 bits are not used. Some signals may not be connected on some versions. See the relevant pin mux data.
ALT_GPIO_PORT_UNKNOWN	Unknown Port - Used to indicate an error.

ALT_GPIO_PORTBIT_e

enum ALT_GPIO_PORTBIT_e

This type definition enumerates the individual bits within the GPIO ports used by the GPIO manager. The bit-ordering must match the hardware bit-ordering. Since the ordering and packing of bitfields is not standardized in C/C++, the following are defined as masks.
For example, to set bits 3 and 4 of GPIO port B outputs (assuming the bits had previously been set to outputs), the user could use the syntax:

alt_gpio_port_data_write(ALT_GPIO_PORTB, ALT_GPIO_BIT3 | ALT_GPIO_BIT4);

Enumerator
ALT_GPIO_BIT0
ALT_GPIO_BIT1
ALT_GPIO_BIT2
ALT_GPIO_BIT3
ALT_GPIO_BIT4
ALT_GPIO_BIT5
ALT_GPIO_BIT6
ALT_GPIO_BIT7
ALT_GPIO_BIT8
ALT_GPIO_BIT9
ALT_GPIO_BIT10
ALT_GPIO_BIT11
ALT_GPIO_BIT12
ALT_GPIO_BIT13
ALT_GPIO_BIT14
ALT_GPIO_BIT15
ALT_GPIO_BIT16
ALT_GPIO_BIT17
ALT_GPIO_BIT18
ALT_GPIO_BIT19
ALT_GPIO_BIT20
ALT_GPIO_BIT21
ALT_GPIO_BIT22
ALT_GPIO_BIT23
ALT_GPIO_BIT24
ALT_GPIO_BIT25
ALT_GPIO_BIT26
ALT_GPIO_BIT27
ALT_GPIO_BIT28

Function Documentation

alt_gpio_init()

ALT_STATUS_CODE alt_gpio_init

(

void

)

Initialize the GPIO modules before use

Return values

ALT_E_SUCCESS	The operation was successful.
ALT_E_ERROR	The operation failed.

alt_gpio_port_config()

ALT_STATUS_CODE alt_gpio_port_config	(	ALT_GPIO_PORT_t	gpio_pid,
		uint32_t	mask,
		ALT_GPIO_PIN_DIR_t	dir,
		ALT_GPIO_PIN_TYPE_t	type,
		ALT_GPIO_PIN_POL_t	pol,
		ALT_GPIO_PIN_DEBOUNCE_t	debounc,
		uint32_t	data
	)

Configures a group of GPIO signals with identical setup parameters. Allows for configuring all parameters of a given port at one time.

Parameters

gpio_pid	The GPIO port identifier.
mask	The group of bits to apply this operation to. Other bits (mask set to zero) are not changed.
dir	Data direction.
type	Edge-triggered or level-triggered interrupts.
pol	Active-high or active-low polarity.
debounc	Debounce signals or not.
data	Set the data output to this value.

Return values

ALT_E_SUCCESS	The operation was successful.
ALT_E_ERROR	The operation failed.
ALT_E_BAD_ARG	Invalid input argument.

alt_gpio_port_data_read()

uint32_t alt_gpio_port_data_read	(	ALT_GPIO_PORT_t	gpio_pid,
		uint32_t	mask
	)

Returns the value of the data inputs of the specified GPIO module. This is the current logic value of the pin, whether set to be an input or an output.
If a given signal is set to be an output, this input value can be read to determine if the pin is grounded, pulled high, or is floating.

Parameters

gpio_pid	The GPIO port identifier.
mask	The group of bits (where mask bits equal one) to return. Other bits (where mask bits equal zero) are returned as zero. Specify mask = ALT_GPIO_BITMASK (0x1FFFFFFF) to return all data bits of the port.

Return values

uint32_t

The current value of the GPIO module input signals.

alt_gpio_port_data_write()

ALT_STATUS_CODE alt_gpio_port_data_write	(	ALT_GPIO_PORT_t	gpio_pid,
		uint32_t	mask,
		uint32_t	val
	)

Sets the GPIO data outputs of the specified GPIO module to a logic one or zero. Outputs are only set if the data direction for those bits is also set to configure them as outputs.

Parameters

gpio_pid	The GPIO port identifier.
mask	The group of bits (mask bits equal one) to apply this operation to. Other bits (mask bits equal zero) are not changed.
val	The 32-bit word to write to the GPIO outputs. Only the 29 LSBs are used. Setting the three MSBs causes an error.

Return values

ALT_E_SUCCESS	The operation was successful.
ALT_E_ERROR	The operation failed.
ALT_E_BAD_ARG	Bad input argument.

alt_gpio_port_datadir_get()

uint32_t alt_gpio_port_datadir_get	(	ALT_GPIO_PORT_t	gpio_pid,
		uint32_t	mask
	)

Returns the data direction configuration of selected bits of the specified GPIO module.

Parameters

gpio_pid	The GPIO port identifier.
mask	The group of bits (where mask bits equal one) to read and return. Other bits (where mask bits equal zero) are returned as zero. Specify mask = ALT_GPIO_BITMASK (0x1FFFFFFF) to return all data direction bits of the port.

Return values

uint32_t

Individual bits are: 0 - The signal is configured as an input. 1 - The signal is configured as an output.

alt_gpio_port_datadir_set()

ALT_STATUS_CODE alt_gpio_port_datadir_set	(	ALT_GPIO_PORT_t	gpio_pid,
		uint32_t	mask,
		uint32_t	config
	)

Sets the specified GPIO data bits to use the data direction(s) specified.

Parameters

gpio_pid	The GPIO port identifier.
mask	The group of bits (where mask bits equal one) to apply this operation to. Other bits (where mask bits equal zero) are not changed. Specify mask = ALT_GPIO_BITMASK (0x1FFFFFFF) to configure all data direction bits of the port.
config	The data-directions of the bits to be set in this operation. Individual bits are: 0 - Use as an input (default). 1 - Use as an output.

Return values

ALT_E_SUCCESS	The operation was successful.
ALT_E_ERROR	The operation failed.
ALT_E_BAD_ARG	Bad input argument.

alt_gpio_port_debounce_get()

uint32_t alt_gpio_port_debounce_get	(	ALT_GPIO_PORT_t	gpio_pid,
		uint32_t	mask
	)

Returns the debounce configuration for the input signals of the specified GPIO register. If debounce is selected, metastability flip-flops are inserted to debounce signals presented to the GPIO inputs.

Parameters

gpio_pid	The GPIO port identifier.
mask	The group of bits (where mask bits equal one) to return. Other bits (where mask bits equal zero) are returned as zero. Specify mask = ALT_GPIO_BITMASK (0x1FFFFFFF) to return all debounce configuration bits of the port.

Return values

uint32_t

The current debounce configuration.Individual bits are: 0 - Debounce is not selected for this signal. 1 - Debounce is selected for this signal.

alt_gpio_port_debounce_set()

ALT_STATUS_CODE alt_gpio_port_debounce_set	(	ALT_GPIO_PORT_t	gpio_pid,
		uint32_t	mask,
		uint32_t	config
	)

Sets the debounce configuration for input signals of the specified GPIO module. If debounce is selected, metastability flip-flops are inserted to debounce signals presented to the GPIO inputs. A signal must be steady for two periods of the gpio_db_clk clock before it is considered valid. The frequency of the gpio_db_clk clock may be set using the Clock Manager API.

Parameters

gpio_pid	The GPIO port identifier.
mask	The group of bits (where mask bits equal one) to apply this operation to. Other bits (where mask bits equal zero) are not changed. Specify mask = ALT_GPIO_BITMASK (0x1FFFFFFF) to configure the debounce setting for all bits of the port.
config	The debounce configuration to set. Individual bits are: 0 - Debounce is not selected for this signal (default). 1 - Debounce is selected for this signal.

Return values

ALT_E_SUCCESS	The operation was successful.
ALT_E_ERROR	The operation failed.
ALT_E_BAD_ARG	Invalid input data.

alt_gpio_port_sync_get()

ALT_STATUS_CODE alt_gpio_port_sync_get

(

ALT_GPIO_PORT_t

gpio_pid

)

Returns the synchronization configuration for the signals of the specified GPIO register. This allows for synchronizing level-sensitive interrupts to the internal clock signal. This is a port-wide option that controls all level-sensitive interrupt signals of that GPIO port.

Parameters

gpio_pid

The GPIO port identifier.

Return values

ALT_E_TRUE	Synchronization to clock is enabled for level-sensitive interrupts.
ALT_E_FALSE	Synchronization to clock is disabled for level-sensitive interrupts.
ALT_E_BAD_ARG	Invalid input argument.

alt_gpio_port_sync_set()

ALT_STATUS_CODE alt_gpio_port_sync_set	(	ALT_GPIO_PORT_t	gpio_pid,
		uint32_t	config
	)

Sets the synchronization configuration for the signals of the specified GPIO register. This allows for synchronizing level-sensitive interrupts to an internal clock signal. This is a port-wide option that controls all level-sensitive interrupt signals of that GPIO port.

Parameters

gpio_pid	The GPIO port identifier.
config	Any non-zero value - Synchronize to internal clock signal. Zero - Do not synchronize to internal clock signal.

Return values

ALT_E_SUCCESS	The operation was successful.
ALT_E_ERROR	The operation failed.
ALT_E_BAD_ARG	Invalid input data.

alt_gpio_uninit()

ALT_STATUS_CODE alt_gpio_uninit

(

void

)

Uninitialize the GPIO modules & return to reset state

Return values

ALT_E_SUCCESS	The operation was successful.
ALT_E_ERROR	The operation failed.