This module contains low level functions GPIO access. More...

Files
file	attiny13a_gpio.h
	Header file for attiny13a GPIO.

Enumerations

Functions
mcu_error	pinSetup (gpio_mode mode, gpio_port port, gpio_pin pin)
	Setup a GPIO pin for a given function. More...

void	pinHigh (gpio_port port, gpio_pin pin)
	Set a given gpio pin on a port to logic high. More...

void	pinLow (gpio_port port, gpio_pin pin)
	Set a given gpio pin on a port to logic low. More...

void	pinWrite (gpio_port port, gpio_pin pin, gpio_state state)
	Set a given gpio pin on a port to a logic state. More...

void	pinToggle (gpio_port port, gpio_pin pin)
	Toggle the output of a given pin on a port. More...

uint8_t	pinRead (gpio_port port, gpio_pin pin)
	Read the current digital value of an input pin. More...

mcu_error	GPIO_ISREnable (gpio_port port, gpio_pin pin, gpio_isr trigger, void(*handle)(void))
	Setup interrupts on a gpio port / pin. More...

mcu_error	GPIO_ISRDisable (gpio_pin pin)
	Disable interrupts on a gpio port / pin. More...

Detailed Description

This module contains low level functions GPIO access.

The attiny13a only has a single GPIO port, port B, with pins numbered 0 - 5. Pin 5 is used for the reset (active low). To use this pin as a regular GPIO the correct fuses need to be set in the Makefile.

Author: Stuart Ianna

Version: 0.1

Date: October 2018

Copyright: GNU GPLv3

Warning: Interrupts also need to be enabled in the Makefile, they are disabled by default to save space.

Bug:: None

Todo:

Verified Compilers

avr-gcc 4.9.2

Minimum working example (blinky): //Change to include appropriate MCU target
#include <stm32f103cb_gpio.h>
int main(void){
//Setup port C pin 13 for digital output
pinSetup(GPIO_DO,PORTC,PIN13);
while(1){
//Toggle the pin's output value
pinToggle(PORTC,PIN13);
//Wait a bit
for(int i = 0; i < 0x7FFF; i++);
}
return 0;
}

Minimum working example (Pin input): //Change to include appropriate MCU target
#include <stm32f103cb_gpio.h>
int main(void){
//Setup port C pin 13 for digital output
pinSetup(GPIO_DO,PORTC,PIN13);
//Setup port A pin 6 for digital input
pinSetup(GPIO_DI,PORTA,PIN6);
while(1){
//Set output to pin input value (Inverse logic);
pinWrite(PORTC,PIN13,pinRead(PORTA,PIN6));
//Wait a bit
for(int i = 0; i < 0x7FFF; i++);
}
return 0;
}

Minimum working example (interrupt): //Change to include appropriate MCU target
#include <stm32f103cb_gpio.h>
//Function to call for interrupt event
void callme(void);
int main(void){
//Setup port C pin 13 for digital output
pinSetup(GPIO_DO,PORTC,PIN13);
//Setup the ISR
GPIO_ISREnable(PORTA, PIN6, GPIO_RISING, &callme);
while(1){
//Do nothing
}
return 0;
}
void callme(void){
//Toggle the pin's output value
pinToggle(PORTC,PIN13);
}

Enumeration Type Documentation

enum gpio_isr

GPIO interrupt options for pins.

corresponds with the memory address offset used.

Warning: Interrupts need to be enabled in the Makefile before they will work. They are disabled by default to save space.

Enumerator
GPIO_RISING	Interrupt occurs on rising edge detection.
GPIO_FALLING	Interrupt occurs on falling edge detection.
GPIO_BOTH	Interrupt occurs on rising and falling edge detection.
GPIO_LEVEL_LOW	Interrupt occurs on low level.

Definition at line 104 of file attiny13a_gpio.h.

enum gpio_mode

GPIO setup options.

These values are used when setting up the pin for use.

Enumerator
GPIO_DI	Setup the port for digital input.
GPIO_DO	Setup the port for digital output.
GPIO_UART_TX	Setup the port for USART transmit.
GPIO_UART_RX	Setup the port for USART receive.
GPIO_I2C	Setup the port for I2C.
GPIO_PWM	Setup the port for output PWM.
GPIO_IC	Setup the port for input capture.
GPIO_ADC	Setup the port for ADC.
GPIO_SPI_OUT	Setup the port for output SPI.
GPIO_SPI_IN	Setup the port for input SPI.

Definition at line 65 of file attiny13a_gpio.h.

enum gpio_pin

GPIO pins available for each port.

These macros are used to access the hardware pins for each port. Each hexidecimal number corresponds with the memory address offset used.

Enumerator
PIN0	Pin 0 of the port.
PIN1	Pin 1 of the port.
PIN2	Pin 2 of the port.
PIN3	Pin 3 of the port.
PIN4	Pin 4 of the port.
PIN5	Pin 5 of the port.

Definition at line 116 of file attiny13a_gpio.h.

enum gpio_port

GPIO ports available for the MCU.

There is only one port available on the Attiny13a. This macro is used for combatability with other MCU

Enumerator
PORTB	Port B of the MCU.

Definition at line 93 of file attiny13a_gpio.h.

enum gpio_state

GPIO pin states.

These values are used when writing a value to a pin with pinWrite().

Enumerator
GPIO_LOW	Set the corresponding pin to logic low.
GPIO_HIGH	Set the corresponding pin to logic high.

Definition at line 82 of file attiny13a_gpio.h.

Function Documentation

mcu_error GPIO_ISRDisable ( gpio_pin pin )

Disable interrupts on a gpio port / pin.

This function clears all previous setting of the interrupt.

Parameters

pin	The pin of the port, defined by gpio_pin

Returns: none

mcu_error GPIO_ISREnable	(	gpio_port	port,
		gpio_pin	pin,
		gpio_isr	trigger,
		void(*)(void)	handle
	)

Setup interrupts on a gpio port / pin.

The MCU can only support one external interrupt. This interrupt is called for every pin which has a mask enabled. Good stradegy is to test which pin could meet the intterupt condition in the main program.

Parameters

port	The port of the MCU, defined by gpio_port
pin	The pin of the port, defined by gpio_pin
trigger	The interrupt trigger, define by gpio_isr
handle	Pointer to the function to be called on interrupt event.

Warning: Interrupts need to be enabled in the Makefile before they will work. They are disabled by default to save space.

Returns: none

void pinHigh	(	gpio_port	port,
		gpio_pin	pin
	)

Set a given gpio pin on a port to logic high.

Pin must be set for digital output to use this function

Parameters

port	The port of the MCU, defined by gpio_port
pin	The pin of the port, defined by gpio_pin

Returns: none.

Definition at line 47 of file attiny13a_gpio.c.

void pinLow	(	gpio_port	port,
		gpio_pin	pin
	)

Set a given gpio pin on a port to logic low.

Pin must be set for digital output to use this function

Parameters

port	The port of the MCU, defined by gpio_port
pin	The pin of the port, defined by gpio_pin

Returns: none.

Definition at line 53 of file attiny13a_gpio.c.

uint8_t pinRead	(	gpio_port	port,
		gpio_pin	pin
	)

Read the current digital value of an input pin.

Pin must be set for digital input to use this function

Parameters

port	The port of the MCU, defined by gpio_port
pin	The pin of the port, defined by gpio_pin

Returns: The value of the pin. 1 = Logic high, 0 = logic low.

Definition at line 78 of file attiny13a_gpio.c.

mcu_error pinSetup	(	gpio_mode	mode,
		gpio_port	port,
		gpio_pin	pin
	)

Setup a GPIO pin for a given function.

This function is also employed by other modules to configure pins and ports.

Parameters

mode	The mode for the pin to operate, defined by gpio_mode
port	The port of the MCU, defined by gpio_port
pin	The pin of the port, defined by gpio_pin

Returns: none.

Definition at line 24 of file attiny13a_gpio.c.

void pinToggle	(	gpio_port	port,
		gpio_pin	pin
	)

Toggle the output of a given pin on a port.

Pin must be set for digital output to use this function

Parameters

port	The port of the MCU, defined by gpio_port
pin	The pin of the port, defined by gpio_pin

Returns: none.

Definition at line 72 of file attiny13a_gpio.c.

void pinWrite	(	gpio_port	port,
		gpio_pin	pin,
		gpio_state	state
	)

Set a given gpio pin on a port to a logic state.

Pin must be set for digital output to use this function

Parameters

state	The state to set the pin to, defined by gpio_state
port	The port of the MCU, defined by gpio_port
pin	The pin of the port, defined by gpio_pin

Returns: none.

Definition at line 59 of file attiny13a_gpio.c.

Files

Enumerations

Functions

Detailed Description

Enumeration Type Documentation

Function Documentation