Library to control push buttons, implemented in C. The library is designed to use only static memory allocation and it can be used with any microcontroller.

• CPU agnostic implementation
• use only static memory allocation
• configurable via macros
• support press, release and hold events
• support callback function for events

Simply copy the content of src directory to your work directory.

The configuration of the library is done by setting 'define' macros in the header file, under the configuration section.

There are two mandatory configurations before the use, the GPIO include file and the setting of the BUTTON_GPIO_GET macro. In the include files section replace the line #include "gpio.h" with the include of your GPIO library. Then, in the configuration section, adjust the macro BUTTON_GPIO_GET to the "get gpio" function of your library.

To use the library with an Arduino the configuration would be:

#include <Arduino.h>  // replace the "gpio.h"
// ...
#define BUTTON_GPIO_GET(port,pin)   digitalRead(pin)

The other settings are preset and can be adjusted as needed. The macro BUTTON_MAX_INSTANCES is used to define the total amount of buttons being controlled by the library. The macro BUTTON_PRESSED_VALUE defines if the logic value read when the button is pressed and the BUTTON_TICK_PERIOD macro is used to set the interrupt service routine (ISR) period.

Once the configuration is done the last required step, before start to use the library, is to place the function button_tick inside one timer ISR. Remember that the period of this timer must match with the value in BUTTON_TICK_PERIOD macro.

Remark: this library does not configure the GPIO direction, you have to do it before use the library functions.

To see more details how to use the library, please check the online API documentation.

MIT