/** * @file ssd1306.c * * 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 */ /********************* * INCLUDES *********************/ #include "assert.h" #include "lvgl_i2c/i2c_manager.h" #include "ssd1306.h" /********************* * DEFINES *********************/ #define TAG "SSD1306" #define OLED_I2C_PORT (CONFIG_LV_I2C_DISPLAY_PORT) // SLA (0x3C) + WRITE_MODE (0x00) = 0x78 (0b01111000) #define OLED_I2C_ADDRESS 0x3C #define OLED_WIDTH 128 #define OLED_HEIGHT 64 #define OLED_COLUMNS 128 #define OLED_PAGES 8 #define OLED_PIXEL_PER_PAGE 8 // Control byte #define OLED_CONTROL_BYTE_CMD_SINGLE 0x80 #define OLED_CONTROL_BYTE_CMD_STREAM 0x00 #define OLED_CONTROL_BYTE_DATA_STREAM 0x40 // Fundamental commands (pg.28) #define OLED_CMD_SET_CONTRAST 0x81 // follow with 0x7F #define OLED_CMD_DISPLAY_RAM 0xA4 #define OLED_CMD_DISPLAY_ALLON 0xA5 #define OLED_CMD_DISPLAY_NORMAL 0xA6 #define OLED_CMD_DISPLAY_INVERTED 0xA7 #define OLED_CMD_DISPLAY_OFF 0xAE #define OLED_CMD_DISPLAY_ON 0xAF // Addressing Command Table (pg.30) #define OLED_CMD_SET_MEMORY_ADDR_MODE 0x20 // follow with 0x00 = HORZ mode #define OLED_CMD_SET_COLUMN_RANGE 0x21 // can be used only in HORZ/VERT mode - follow with 0x00 and 0x7F = COL127 #define OLED_CMD_SET_PAGE_RANGE 0x22 // can be used only in HORZ/VERT mode - follow with 0x00 and 0x07 = PAGE7 // Hardware Config (pg.31) #define OLED_CMD_SET_DISPLAY_START_LINE 0x40 #define OLED_CMD_SET_SEGMENT_REMAP 0xA1 #define OLED_CMD_SET_MUX_RATIO 0xA8 // follow with 0x3F = 64 MUX #define OLED_CMD_SET_COM_SCAN_MODE_NORMAL 0xC0 #define OLED_CMD_SET_COM_SCAN_MODE_REMAP 0xC8 #define OLED_CMD_SET_DISPLAY_OFFSET 0xD3 // follow with 0x00 #define OLED_CMD_SET_COM_PIN_MAP 0xDA // follow with 0x12 #define OLED_CMD_NOP 0xE3 // NOP // Timing and Driving Scheme (pg.32) #define OLED_CMD_SET_DISPLAY_CLK_DIV 0xD5 // follow with 0x80 #define OLED_CMD_SET_PRECHARGE 0xD9 // follow with 0xF1 #define OLED_CMD_SET_VCOMH_DESELCT 0xDB // follow with 0x30 // Charge Pump (pg.62) #define OLED_CMD_SET_CHARGE_PUMP 0x8D // follow with 0x14 /********************** * TYPEDEFS **********************/ /********************** * STATIC PROTOTYPES **********************/ static uint8_t send_data(lv_disp_drv_t *disp_drv, void *bytes, size_t bytes_len); static uint8_t send_pixels(lv_disp_drv_t *disp_drv, void *color_buffer, size_t buffer_len); /********************** * STATIC VARIABLES **********************/ /********************** * MACROS **********************/ #define BIT_SET(a,b) ((a) |= (1U<<(b))) #define BIT_CLEAR(a,b) ((a) &= ~(1U<<(b))) /********************** * GLOBAL FUNCTIONS **********************/ void ssd1306_init(void) { uint8_t orientation_1 = 0; uint8_t orientation_2 = 0; #if defined (CONFIG_DISPLAY_ORIENTATION_LANDSCAPE) orientation_1 = OLED_CMD_SET_SEGMENT_REMAP; orientation_2 = OLED_CMD_SET_COM_SCAN_MODE_REMAP; #elif defined (CONFIG_DISPLAY_ORIENTATION_LANDSCAPE_INVERTED) orientation_1 = 0xA0; orientation_2 = OLED_CMD_SET_COM_SCAN_MODE_NORMAL; #else assert(false); // Invalid configuration of SSD1306 driver #endif uint8_t display_mode = 0; #if defined CONFIG_LV_INVERT_COLORS display_mode = OLED_CMD_DISPLAY_INVERTED; #else display_mode = OLED_CMD_DISPLAY_NORMAL; #endif uint8_t conf[] = { OLED_CONTROL_BYTE_CMD_STREAM, OLED_CMD_SET_CHARGE_PUMP, 0x14, orientation_1, orientation_2, OLED_CMD_SET_CONTRAST, 0xFF, display_mode, OLED_CMD_DISPLAY_ON }; uint8_t err = send_data(NULL, conf, sizeof(conf)); assert(0 == err); } 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) { uint16_t byte_index = x + (( y>>3 ) * buf_w); uint8_t bit_index = y & 0x7; if ((color.full == 0) && (LV_OPA_TRANSP != opa)) { BIT_SET(buf[byte_index], bit_index); } else { BIT_CLEAR(buf[byte_index], bit_index); } } void ssd1306_flush(lv_disp_drv_t * disp_drv, const lv_area_t * area, lv_color_t * color_p) { /* Divide by 8 */ uint8_t row1 = area->y1 >> 3; uint8_t row2 = area->y2 >> 3; uint8_t conf[] = { OLED_CONTROL_BYTE_CMD_STREAM, OLED_CMD_SET_MEMORY_ADDR_MODE, 0x00, OLED_CMD_SET_COLUMN_RANGE, (uint8_t) area->x1, (uint8_t) area->x2, OLED_CMD_SET_PAGE_RANGE, row1, row2, }; uint8_t err = send_data(disp_drv, conf, sizeof(conf)); assert(0 == err); err = send_pixels(disp_drv, color_p, OLED_COLUMNS * (1 + row2 - row1)); assert(0 == err); lv_disp_flush_ready(disp_drv); } void ssd1306_rounder(lv_disp_drv_t * disp_drv, lv_area_t *area) { uint8_t hor_max = disp_drv->hor_res; uint8_t ver_max = disp_drv->ver_res; area->x1 = 0; area->y1 = 0; area->x2 = hor_max - 1; area->y2 = ver_max - 1; } void ssd1306_sleep_in(void) { uint8_t conf[] = { OLED_CONTROL_BYTE_CMD_STREAM, OLED_CMD_DISPLAY_OFF }; uint8_t err = send_data(NULL, conf, sizeof(conf)); assert(0 == err); } void ssd1306_sleep_out(void) { uint8_t conf[] = { OLED_CONTROL_BYTE_CMD_STREAM, OLED_CMD_DISPLAY_ON }; uint8_t err = send_data(NULL, conf, sizeof(conf)); assert(0 == err); } /********************** * STATIC FUNCTIONS **********************/ static uint8_t send_data(lv_disp_drv_t *disp_drv, void *bytes, size_t bytes_len) { (void) disp_drv; uint8_t *data = (uint8_t *) bytes; return lvgl_i2c_write(OLED_I2C_PORT, OLED_I2C_ADDRESS, data[0], data + 1, bytes_len - 1 ); } static uint8_t send_pixels(lv_disp_drv_t *disp_drv, void *color_buffer, size_t buffer_len) { (void) disp_drv; return lvgl_i2c_write(OLED_I2C_PORT, OLED_I2C_ADDRESS, OLED_CONTROL_BYTE_DATA_STREAM, color_buffer, buffer_len); }