lvgl_helpers.c File Reference

#include "lvgl_helpers.h"
#include "esp_log.h"

Include dependency graph for lvgl_helpers.c:

Macros
#define	TAG   "lvgl_helpers_ssd1306"
#define	BIT_SET(a, b)   ((a) |= (1U << (b)))
#define	BIT_CLEAR(a, b)   ((a) &= ~(1U << (b)))

Functions
void	ssd1306_init (void)
	Initialize ssd1306 device. More...
void	ssd1306_set_px_cb (lv_disp_drv_t *disp_drv, uint8_t *buf, lv_coord_t buf_w, lv_coord_t x, lv_coord_t y, lv_color_t color, lv_opa_t opa)
	Draw a pixel into the buffer. More...
void	ssd1306_flush (lv_disp_drv_t *disp_drv, const lv_area_t *area, lv_color_t *color_p)
	Flush the buffer on the screen. More...
void	ssd1306_rounder (lv_disp_drv_t *disp_drv, lv_area_t *area)
	Round the area that needs to be updated. More...
void	ssd1306_sleep_in (void)
	Turn off the display. More...
void	ssd1306_sleep_out (void)
	Turn on the display. More...
bool	lvgl_i2c_driver_init (int sda_pin, int scl_pin, int speed_hz)
	Initialize LVGL I2C Master. More...

Macro Definition Documentation

BIT_CLEAR

#define BIT_CLEAR	(		a,
			b
	)		((a) &= ~(1U << (b)))

BIT_SET

#define BIT_SET	(		a,
			b
	)		((a) |= (1U << (b)))

TAG

#define TAG   "lvgl_helpers_ssd1306"

Code from https://github.com/yanbe/ssd1306-esp-idf-i2c.git is used as a starting point, in addition to code from https://github.com/espressif/esp-iot-solution.

Definitions are borrowed from: http://robotcantalk.blogspot.com/2015/03/interfacing-arduino-with-ssd1306-driven.html

For LVGL the forum has been used, in particular: https://blog.littlevgl.com/2019-05-06/oled

Function Documentation

lvgl_i2c_driver_init()

bool lvgl_i2c_driver_init	(	int	sda_pin,
		int	scl_pin,
		int	speed_hz
	)

Initialize LVGL I2C Master.

Parameters

sda_pin	gpio number for I2C master data
scl_pin	gpio number for I2C master clock
speed_hz	I2C master clock frequency

Returns

esp_err_t returns ESP_OK if I2C is initialized successfully, else the appropriate error code

ssd1306_flush()

void ssd1306_flush	(	lv_disp_drv_t *	drv,
		const lv_area_t *	area,
		lv_color_t *	color_map
	)

Flush the buffer on the screen.

Parameters

drv	pointer to the display driver structure
area	represents an area on the screen
color_map	represents the color map

ssd1306_init()

void ssd1306_init

(

void

)

Initialize ssd1306 device.

Returns

esp_err_t returns ESP_OK if I2C is initialized successfully, else the appropriate error code

ssd1306_rounder()

void ssd1306_rounder	(	lv_disp_drv_t *	disp_drv,
		lv_area_t *	area
	)

Round the area that needs to be updated.

Parameters

drv	pointer to the display driver structure
area	represents an area on the screen

ssd1306_set_px_cb()

void ssd1306_set_px_cb	(	lv_disp_drv_t *	disp_drv,
		uint8_t *	buf,
		lv_coord_t	buf_w,
		lv_coord_t	x,
		lv_coord_t	y,
		lv_color_t	color,
		lv_opa_t	opa
	)

Draw a pixel into the buffer.

Parameters

disp_drv	pointer to the display driver structure
buf	pointer to the memory range where you want to update the data
buf_w	width of the range where you want to update the data
x	x co-ordinate of pixel to update
y	y co-ordinate of pixel to update
color	monochrome color setting, either full or clear
opa	opacity value

ssd1306_sleep_in()

void ssd1306_sleep_in

(

void

)

Turn off the display.

ssd1306_sleep_out()

void ssd1306_sleep_out

(

void

)

Turn on the display.