klips/esp/cpp/07_lcd-panel/main/display.cpp
2025-02-15 14:13:42 -05:00

228 lines
7.2 KiB
C++

#include "display.h"
#include "ssd1306.h"
#include "widgets/label/lv_label.h"
#include <esp_log.h>
#include <esp_lcd_panel_ops.h>
#include <esp_heap_caps.h>
#include <esp_lcd_panel_io.h>
#include <esp_timer.h>
#include <lv_init.h>
#include <display/lv_display.h>
#include <driver/i2c_master.h>
#include <mutex>
// LVGL library is not thread-safe, this example calls LVGL APIs from tasks.
// We must use a mutex to protect it.
_lock_t ScopedLock::lock_;
Display::Display(const I2C &i2c) :
panel_(i2c)
{
if (!lv_is_initialized()) {
ESP_LOGI(TAG, "Initialize LVGL");
lv_init();
}
// Create a lvgl display.
// TODO: Use PanelDevice functions to get SSD1306 specs
display_ = lv_display_create(LCD_H_RES, LCD_V_RES);
// associate the i2c panel handle to the display
lv_display_set_user_data(display_, panel_.get());
// Create draw buffer.
ESP_LOGI(TAG, "Allocate separate LVGL draw buffers");
// TODO: Use PanelDevice functions to get SSD1306 specs
buf_size_ = LCD_H_RES * LCD_V_RES / 8 + LVGL_PALETTE_SIZE;
buf_ = heap_caps_calloc(1, buf_size_, MALLOC_CAP_INTERNAL | MALLOC_CAP_8BIT);
assert(buf_);
// LVGL9 suooprt new monochromatic format.
lv_display_set_color_format(display_, LV_COLOR_FORMAT_I1);
// Initialize LVGL draw buffers.
lv_display_set_buffers(display_, buf_, nullptr, buf_size_,
LV_DISPLAY_RENDER_MODE_FULL);
lv_display_set_rotation(display_, LV_DISPLAY_ROTATION_0);
// Set callback which can copy the rendered image to an area of the display.
lv_display_set_flush_cb(display_, Display::lvgl_flush_cb);
ESP_LOGI(TAG, "Register io panel callback for LVGL flush ready notification");
const esp_lcd_panel_io_callbacks_t cbs = {
.on_color_trans_done = Display::lvgl_flush_ready,
};
/* Register done callback */
ESP_ERROR_CHECK(
esp_lcd_panel_io_register_event_callbacks(panel_.io_handle_, &cbs,
display_));
// TODO: What is this
ESP_LOGI(TAG, "Use esp_timer as LVGL tick timer");
const esp_timer_create_args_t lvgl_tick_timer_args = {
.callback = &Display::lvgl_increase_tick,
.name = "lvgl_tick"
};
esp_timer_handle_t lvgl_tick_timer = nullptr;
ESP_ERROR_CHECK(esp_timer_create(&lvgl_tick_timer_args, &lvgl_tick_timer));
ESP_ERROR_CHECK(esp_timer_start_periodic(lvgl_tick_timer,
LVGL_TICK_PERIOD_MS * 1000));
ESP_LOGI(TAG, "Create LVGL task");
xTaskCreate(Display::lvgl_port_task, "LVGL", LVGL_TASK_STACK_SIZE,
nullptr, LVGL_TASK_PRIORITY, nullptr);
}
void Display::set_text(const char *text,
const char *name,
lv_label_long_mode_t long_mode,
lv_align_t align)
{
// Lock the mutex due to the LVGL APIs are not thread-safe.
ScopedLock lock;
ESP_LOGI(TAG, "Display LVGL Scroll Text");
lv_obj_t *scr = lv_display_get_screen_active(display_);
objects_[name] = lv_label_create(scr);
// Circular scroll.
auto obj = objects_[name];
lv_label_set_long_mode(obj, long_mode);
lv_label_set_text(obj, text);
// Set the size of the screen.
// If you use rotation 90 or 270 use lv_display_get_vertical_resolution.
lv_obj_set_width(obj, lv_display_get_horizontal_resolution(display_));
lv_obj_align(obj, align, 0, 0);
}
bool Display::lvgl_flush_ready(esp_lcd_panel_io_handle_t,
esp_lcd_panel_io_event_data_t *,
void *user_ctx)
{
auto *disp = (lv_display_t *) user_ctx;
lv_display_flush_ready(disp);
return false;
}
void Display::lvgl_flush_cb(lv_display_t *display, const lv_area_t *area,
uint8_t *px_map)
{
auto panel_handle =
(esp_lcd_panel_handle_t) lv_display_get_user_data(display);
// Necessary because LVGL reserves 2x4 bytes in the buffer for a palette.
// For more information about the monochrome, please refer to:
// https://docs.lvgl.io/9.2/porting/display.html#monochrome-displays
// Skip the palette here.
px_map += LVGL_PALETTE_SIZE;
uint16_t hor_res = lv_display_get_physical_horizontal_resolution(display);
int32_t x1 = area->x1;
int32_t x2 = area->x2;
int32_t y1 = area->y1;
int32_t y2 = area->y2;
for (int32_t y = y1; y <= y2; y++) {
for (int32_t x = x1; x <= x2; x++) {
/* The order of bits is MSB first.
MSB LSB
bits 7 6 5 4 3 2 1 0
pixels 0 1 2 3 4 5 6 7
Left Right
*/
bool chroma_color = (px_map[(hor_res >> 3) * y + (x >> 3)] &
1 << (7 - x % 8));
// Write to the buffer as required for the display.
// It writes only 1-bit for monochrome displays mapped vertically.
uint8_t *buf = SSD1306::oled_buffer_ + hor_res * (y >> 3) + (x);
if (chroma_color) {
(*buf) &= ~(1 << (y % 8));
} else {
(*buf) |= (1 << (y % 8));
}
}
}
// Pass the draw buffer to the driver.
ESP_ERROR_CHECK(
esp_lcd_panel_draw_bitmap(panel_handle, x1, y1, x2 + 1, y2 + 1,
SSD1306::oled_buffer_));
}
void Display::lvgl_increase_tick(void *)
{
// Tell LVGL how many milliseconds has elapsed
lv_tick_inc(LVGL_TICK_PERIOD_MS);
}
[[noreturn]] void Display::lvgl_port_task(void *)
{
ESP_LOGI(TAG, "Starting LVGL task");
for (uint32_t time_till_next_ms = 0; true;) {
_lock_acquire(&ScopedLock::lock_);
time_till_next_ms = lv_timer_handler();
_lock_release(&ScopedLock::lock_);
usleep(1000 * time_till_next_ms);
}
}
I2C::I2C() :
i2c_bus_(nullptr),
bus_config_(
(i2c_master_bus_config_t) {
.i2c_port = I2C_BUS_PORT,
.sda_io_num = PIN_SDA,
.scl_io_num = PIN_SCL,
.clk_source = I2C_CLK_SRC_DEFAULT,
.glitch_ignore_cnt = 7,
.flags {
.enable_internal_pullup = true,
},
}
)
{
ESP_LOGI(TAG, "Initialize I2C bus");
ESP_ERROR_CHECK(i2c_new_master_bus(&bus_config_, &i2c_bus_));
}
Panel::Panel(i2c_master_bus_handle_t i2c) :
io_handle_(nullptr),
panel_(nullptr),
// According to SSD1306 datasheet
panel_config_(
(esp_lcd_panel_dev_config_t) {
.reset_gpio_num = PIN_RST,
.bits_per_pixel = 1,
}
),
// According to SSD1306 datasheet
io_config_(
(esp_lcd_panel_io_i2c_config_t) {
.dev_addr = I2C_HW_ADDR,
.control_phase_bytes = 1,
.dc_bit_offset = 6,
.lcd_cmd_bits = LCD_CMD_BITS,
.lcd_param_bits = LCD_CMD_BITS,
.scl_speed_hz = LCD_PIXEL_CLOCK_HZ,
}
)
{
ESP_LOGI(TAG, "Install panel IO");
ESP_ERROR_CHECK(esp_lcd_new_panel_io_i2c(i2c, &io_config_, &io_handle_));
ESP_LOGI(TAG, "Install SSD1306 panel driver");
SSD1306 ssd1306(
(esp_lcd_panel_ssd1306_config_t) {
.height = LCD_V_RES,
}
);
ssd1306.create_panel(panel_config_, io_handle_, panel_);
ESP_LOGI(TAG, "Resetting panel display");
ESP_ERROR_CHECK(esp_lcd_panel_reset(panel_));
ESP_LOGI(TAG, "Initializing panel display");
ESP_ERROR_CHECK(esp_lcd_panel_init(panel_));
ESP_LOGI(TAG, "Turning on panel display");
ESP_ERROR_CHECK(esp_lcd_panel_disp_on_off(panel_, true));
}