ssd1306_i2c.h

/*************************************************************************
* About  : SSD1306 OLED Driver Programm(using I2C Interface)
*          Depend on lib wiringPi
* Author : Xiang,Zuo
* Mail   : xianglinks@gmail.com
* Date   : 2016-03-20
* Ver    : 0.3
**************************************************************************/

#ifndef SSD1306_I2C_H
#define SSD1306_I2C_H

// --- Define functions ---
// ----------------------------------------------
/**
 * @brief ssd1306I2CSetup
 *
 * @param i2cAddr: I2C device address
 *        on Rpi, you can use i2cdetect -y 1 to get addr
 *
 * @return standard file descriptor for I2C operations
 */
int ssd1306I2CSetup(unsigned char i2cAddr);

// send command byte to SSD1306 via I2C
void sendCommand(int fd, unsigned char command);
// send data byte to SSD1306 via I2C
void sendData(int fd, unsigned char data);

// OLED operations
void displayOn(int fd);  // turn on the display
void displayOff(int fd);  // turn off the display
void clearDisplay(int fd);  // clear the contents on display


// Attention: The draw and draw_line functions only change the contents in local data frame
//            To update the contents on display should function updateDisplay() be used

/**
 * @brief draw one ascii code at determined position
 *
 * @param x: 1 to 4
 * @param y: 1 to 16
 * @param ascii: one ascii code
 */
void draw(int x,int y,unsigned char ascii);

/**
 * @brief draw one line of ascii codes at determined position on display
 *
 * @param x: 1 to 4
 * @param y: 1 to 16
 * @param ascii_str[16]: the number of ascii codes can not more than 16
 */
void draw_line(int x ,int y,unsigned char ascii_str[16]);

/**
 * @brief write the frame data to SSD1306 to update display
 *
 * @param fd: file descriptor
 */
void updateDisplay(int fd);
// ----------------------------------------------

// --- Define constants ----
// infos can be found in SSD1306 datasheet
// ----------------------------------------------
// commands
#define SSD1306_DISPLAYON 0xAF
#define SSD1306_DISPLAYOFF 0xAE
#define SSD1306_NORMALDISPLAY 0xA6
#define SSD1306_INVERTDISPLAY 0xA7
#define SSD1306_MULTIPLEX_RATIO 0xA8

// registers
#define SSD1306_CONTROL_REG 0x00  // Co = 0, DC = 0
#define SSD1306_DATA_REG 0x40
// ----------------------------------------------

#endif /* SSD1306_I2C_H */