ajaybhargav / hal

Hardware Abstraction Layer (HAL) for Littlev Graphical Library to access display, touch pad and sys. tick

Hardware Abstraction Layer (HAL) for Littlev Graphics Library

This repository contains and example Hardware Abstraction Layer (HAL) for Littlev Graphics Library. The graphics library uses the functions in these files to access to your:

• Display
• Touch pad
• System tick

In the HAL you have to write only 5 simple functions.

Display drivers (hal/disp)

To access to the display 2 functions are used:

disp_fill(x1, y1, x2, y2, color)Fill a rectangular area with a color

disp_map(x1, y1, x2, y2, color_array)Copy an array of colors to a rectangular area

Input device (hal/indev)

You can use multiple input devices for example a touch pad and some buttons which are pressing specific points on the display

indev_get(id, *x, *y) Read the x and y coordinates from an input device. Return false if the input device released, true is pressed.

In indev.h you have to define INDEV_NUM according to the number of input devices. For example if you are using only a touch pad: #define INDEV_NUM 1

System tick (hal/systick)

You have to provide possibility to get a system tick counter with 1 ms resolution.

systick_get() Get the elapsed milliseconds since start up

The systick_elaps(prev_time) function is also required but is already have been written.

The systick_add_cb(func) and systick_rem_cb(func) are optional and are required only fro some specific components from the [Misc. Library] (https://github.com/littlevgl/misc)