Files
Calendink/components/epd/epd.cpp
T

459 lines
12 KiB
C++

#include <assert.h>
#include <string.h>
#include "driver/gpio.h"
#include "driver/spi_master.h"
#include "esp_log.h"
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include <time.h>
#include "epd.hpp"
internal const char *kTagEPD = "EPD";
internal spi_device_handle_t g_spi_handle;
internal bool g_is_asleep = true;
internal constexpr size_t kTotal_bytes = (EPD_WIDTH * EPD_HEIGHT) / 8;
internal uint8 g_scratch_buffer[4096];
internal struct epd_refresh_stats{
time_t last_full_refresh_bw;
int fast_count_bw;
time_t last_full_refresh_4g;
int fast_count_4g;
} g_epd_stats = {0, 0, 0, 0};
internal void epd_spi_init(void)
{
// 1. Initialize the SPI Bus
spi_bus_config_t buscfg = {};
buscfg.miso_io_num =
TFT_MISO; // Initialize MISO as input, matching `spi.begin(TFT_SCLK,
// TFT_MISO, TFT_MOSI, -1)`
buscfg.mosi_io_num = TFT_MOSI;
buscfg.sclk_io_num = TFT_SCLK;
buscfg.quadwp_io_num = -1;
buscfg.quadhd_io_num = -1;
buscfg.max_transfer_sz = 4096;
// SPI2_HOST is the general-purpose SPI host on ESP32-S3
ESP_ERROR_CHECK(spi_bus_initialize(SPI2_HOST, &buscfg, SPI_DMA_CH_AUTO));
// 2. Add the EPD device to the bus
spi_device_interface_config_t devcfg = {};
devcfg.clock_speed_hz = SPI_FREQUENCY;
devcfg.mode = 0; // Standard EPD SPI mode
devcfg.spics_io_num = TFT_CS; // The driver handles CS automatically
devcfg.queue_size = 7;
devcfg.flags = 0;
ESP_ERROR_CHECK(spi_bus_add_device(SPI2_HOST, &devcfg, &g_spi_handle));
}
internal void epd_gpio_init()
{
gpio_reset_pin((gpio_num_t)TFT_BUSY);
gpio_set_direction((gpio_num_t)TFT_BUSY, GPIO_MODE_INPUT);
gpio_reset_pin((gpio_num_t)TFT_RST);
gpio_set_direction((gpio_num_t)TFT_RST, GPIO_MODE_OUTPUT);
gpio_set_level((gpio_num_t)TFT_RST,
1); // Set high, do not share pin with another SPI device
gpio_reset_pin((gpio_num_t)TFT_DC);
gpio_set_direction((gpio_num_t)TFT_DC, GPIO_MODE_OUTPUT);
gpio_set_level((gpio_num_t)TFT_DC, 1); // Data/Command high = data mode
gpio_reset_pin((gpio_num_t)TFT_CS);
gpio_set_direction((gpio_num_t)TFT_CS, GPIO_MODE_OUTPUT);
gpio_set_level((gpio_num_t)TFT_CS, 1); // Chip select high (inactive)
}
internal void epd_writecommand(unsigned char command)
{
assert(!g_is_asleep);
// Pull DC Low for Command
gpio_set_level((gpio_num_t)TFT_DC, GPIO_LOW);
spi_transaction_t t = {};
t.length = 8; // length in bits
t.tx_buffer = &command;
spi_device_transmit(g_spi_handle, &t);
}
internal void epd_write_buffer(const uint8 *data, size_t len)
{
assert(!g_is_asleep);
if (len == 0)
return;
// Pull DC High for Data
gpio_set_level((gpio_num_t)TFT_DC, GPIO_HIGH);
int chunk_count = 0;
while (len > 0)
{
// max_transfer_sz is typically 4096 which is the limit for a single SPI
// transaction
size_t chunk = (len > 4096) ? 4096 : len;
spi_transaction_t t = {};
t.length = chunk * 8; // length in bits
t.tx_buffer = data;
spi_device_transmit(g_spi_handle, &t);
data += chunk;
len -= chunk;
// Yield every 16 chunks (~64KB) to prevent task watchdog timeout
if (++chunk_count % 16 == 0)
{
vTaskDelay(1);
}
}
}
internal void epd_fill_layer(uint8 cmd, uint8 color_byte)
{
epd_writecommand(cmd);
memset(g_scratch_buffer, color_byte, sizeof(g_scratch_buffer));
size_t remaining = kTotal_bytes;
while (remaining > 0)
{
size_t to_write =
(remaining > sizeof(g_scratch_buffer)) ? sizeof(g_scratch_buffer) : remaining;
epd_write_buffer(g_scratch_buffer, to_write);
remaining -= to_write;
}
}
void epd_writedata(unsigned char data) { epd_write_buffer(&data, 1); }
internal void epd_wait_until_idle()
{
// BUSY pin on this board: LOW = busy, HIGH = idle
// (opposite of GDEY075T7 reference driver)
while (gpio_get_level((gpio_num_t)TFT_BUSY) == 0)
{
vTaskDelay(pdMS_TO_TICKS(5));
}
}
void epd_init(void)
{
ESP_LOGI(kTagEPD, "Initializing EPaper Driver");
epd_gpio_init();
epd_spi_init();
ESP_LOGI(kTagEPD, "EPaper Driver initialized successfully");
}
void epd_shutdown(void)
{
spi_bus_remove_device(g_spi_handle);
spi_bus_free(SPI2_HOST);
}
internal void epd_init_display_full(void)
{
ESP_LOGI(kTagEPD, "Performing FULL initialization");
epd_writecommand(0x01); // POWER SETTING
epd_writedata(0x07);
epd_writedata(0x07);
epd_writedata(0x3f);
epd_writedata(0x3f);
epd_writecommand(0x06); // Booster Soft Start
epd_writedata(0x17);
epd_writedata(0x17);
epd_writedata(0x28);
epd_writedata(0x17);
epd_writecommand(0x04); // POWER ON
vTaskDelay(pdMS_TO_TICKS(100));
epd_wait_until_idle();
epd_writecommand(0X00); // PANEL SETTING
epd_writedata(0x1F);
epd_writecommand(0x61); // TRES
epd_writedata(EPD_WIDTH >> 8);
epd_writedata(EPD_WIDTH & 0xFF);
epd_writedata(EPD_HEIGHT >> 8);
epd_writedata(EPD_HEIGHT & 0xFF);
epd_writecommand(0x15);
epd_writedata(0x00);
epd_writecommand(0x50); // VCOM AND DATA INTERVAL SETTING
epd_writedata(0x29); // BDV=10 (White Border), N2OCP=1 (Auto-copy NEW to OLD),
// DDX=01 (0=Black, 1=White)
epd_writedata(0x07);
epd_writecommand(0x60); // TCON SETTING
epd_writedata(0x22);
}
internal void epd_init_display_fast(void)
{
ESP_LOGI(kTagEPD, "Performing FAST initialization");
epd_writecommand(0X00); // PANEL SETTING
epd_writedata(0x1F);
epd_writecommand(0x50); // VCOM AND DATA INTERVAL SETTING
epd_writedata(0x29);
epd_writedata(0x07);
epd_writecommand(0x04); // POWER ON
vTaskDelay(pdMS_TO_TICKS(100));
epd_wait_until_idle();
// Enhanced display drive (Booster values for fast mode)
epd_writecommand(0x06); // Booster Soft Start
epd_writedata(0x27);
epd_writedata(0x27);
epd_writedata(0x18);
epd_writedata(0x17);
epd_writecommand(0xE0);
epd_writedata(0x02);
epd_writecommand(0xE5);
epd_writedata(0x5A);
}
internal void epd_init_display_4g_full(void)
{
ESP_LOGI(kTagEPD, "Performing FULL 4-GRAY initialization");
epd_writecommand(0X00); // PANEL SETTING
epd_writedata(0x1F);
epd_writecommand(0X50); // VCOM AND DATA INTERVAL SETTING
epd_writedata(0x29);
epd_writedata(0x07);
epd_writecommand(0x04); // POWER ON
vTaskDelay(pdMS_TO_TICKS(100)); // Standard delay for full
epd_wait_until_idle();
// Standard display drive (Full Booster values)
epd_writecommand(0x06); // Booster Soft Start
epd_writedata(0x17);
epd_writedata(0x17);
epd_writedata(0x28);
epd_writedata(0x17);
epd_writecommand(0xE0);
epd_writedata(0x02);
epd_writecommand(0xE5);
epd_writedata(0x5F); // 0x5F -- 4 Gray
}
internal void epd_init_display_4g_fast(void)
{
ESP_LOGI(kTagEPD, "Performing FAST 4-GRAY initialization");
epd_writecommand(0X00); // PANEL SETTING
epd_writedata(0x1F);
epd_writecommand(0X50); // VCOM AND DATA INTERVAL SETTING
epd_writedata(0x29);
epd_writedata(0x07);
epd_writecommand(0x04); // POWER ON
vTaskDelay(pdMS_TO_TICKS(10));
epd_wait_until_idle();
// Enhanced display drive (Fast Booster values)
epd_writecommand(0x06); // Booster Soft Start
epd_writedata(0x27);
epd_writedata(0x27);
epd_writedata(0x18);
epd_writedata(0x17);
epd_writecommand(0xE0);
epd_writedata(0x02);
epd_writecommand(0xE5);
epd_writedata(0x5F); // 0x5F -- 4 Gray
}
void epd_init_display(bool is_4gray)
{
g_is_asleep = false;
// Module reset
gpio_set_level((gpio_num_t)TFT_RST, 0);
vTaskDelay(pdMS_TO_TICKS(10));
gpio_set_level((gpio_num_t)TFT_RST, 1);
vTaskDelay(pdMS_TO_TICKS(10));
time_t now = time(NULL);
if (is_4gray)
{
double diff = difftime(now, g_epd_stats.last_full_refresh_4g);
bool force_full = (g_epd_stats.last_full_refresh_4g == 0) || (diff > 86400.0) ||
(g_epd_stats.fast_count_4g >= 5);
if (force_full)
{
epd_init_display_4g_full();
g_epd_stats.last_full_refresh_4g = now;
g_epd_stats.fast_count_4g = 0;
}
else
{
epd_init_display_4g_fast();
g_epd_stats.fast_count_4g++;
}
ESP_LOGI(kTagEPD, "4G Refresh stats: (Fast count: %d/5, Age: %.1f hours)",
g_epd_stats.fast_count_4g, diff / 3600.0);
}
else
{
double diff = difftime(now, g_epd_stats.last_full_refresh_bw);
bool force_full = (g_epd_stats.last_full_refresh_bw == 0) || (diff > 86400.0) ||
(g_epd_stats.fast_count_bw >= 5);
if (force_full)
{
epd_init_display_full();
g_epd_stats.last_full_refresh_bw = now;
g_epd_stats.fast_count_bw = 0;
}
else
{
epd_init_display_fast();
g_epd_stats.fast_count_bw++;
}
ESP_LOGI(kTagEPD, "BW Refresh stats: (Fast count: %d/5, Age: %.1f hours)",
g_epd_stats.fast_count_bw, diff / 3600.0);
}
}
void epd_shutdown_display(void)
{
assert(!g_is_asleep);
ESP_LOGI(kTagEPD, "Shutting down display (Power Off)");
epd_writecommand(0x50); // VCOM AND DATA INTERVAL SETTING (pre-sleep)
epd_writedata(0xF7);
epd_writecommand(0x02); // POWER OFF
epd_wait_until_idle();
epd_writecommand(0x07); // DEEP SLEEP
epd_writedata(0xA5); // Deep sleep check code
vTaskDelay(pdMS_TO_TICKS(10));
g_is_asleep = true;
}
void epd_refresh(void)
{
assert(!g_is_asleep);
ESP_LOGI(kTagEPD, "Refreshing display...");
epd_writecommand(0x12); // REFRESH
vTaskDelay(pdMS_TO_TICKS(1));
epd_wait_until_idle();
}
bool epd_is_asleep(void) { return g_is_asleep; }
void epd_clear(epd_color level)
{
uint8 color_byte = static_cast<uint8>(level);
ESP_LOGI(kTagEPD, "Clearing display (byte=0x%02X)", color_byte);
epd_fill_layer(0x10,
0xFF); // Old data layer (0xFF is mapped to White)
epd_fill_layer(0x13, color_byte); // New data layer
ESP_LOGI(kTagEPD, "Data transmission complete (Refresh required)");
}
void epd_draw_bitmap(epd_color clearColor, const uint8 *bitmap)
{
uint8 color_byte = static_cast<uint8>(clearColor);
ESP_LOGI(kTagEPD, "Drawing bitmap (clearColor byte=0x%02X)", color_byte);
epd_fill_layer(0x10, color_byte); // Send clear color to "Old" layer
epd_writecommand(0x13); // "New" data layer
epd_write_buffer(bitmap, kTotal_bytes);
ESP_LOGI(kTagEPD, "Data transmission complete (Refresh required)");
}
void epd_draw_bitmap_grayscale(epd_color clearColor, const uint8 *bitmap)
{
ESP_LOGI(kTagEPD, "Drawing 4-GRAY bitmap (with unpacking)");
// THE LOGIC:
// The input bitmap is 2-bits per pixel packed (4 pixels per byte).
// Total pixels: 800 * 480 = 384,000.
// Input size: 384,000 / 4 = 96,000 bytes.
// Output: Two frames of 800 * 480 / 8 = 48,000 bytes each.
auto process_layer = [&](uint8 cmd, bool is_new_layer)
{
epd_writecommand(cmd);
size_t scratch_idx = 0;
// Process 48,000 output bytes (each covers 8 pixels)
for (size_t i = 0; i < 48000; i++)
{
uint8 output_byte = 0;
// Each output byte comes from 2 input bytes (j=0, j=1)
for (int j = 0; j < 2; j++)
{
uint8 input_byte = bitmap[i * 2 + j];
// Extract 4 pixels from each input byte
for (int k = 0; k < 4; k++)
{
uint8 pixel_bits = (input_byte >> (6 - k * 2)) & 0x03; // Correct bit order
bool bit_val = false;
if (is_new_layer)
{
// NEW Layer (0x13) Mapping
if (pixel_bits == 0x03) bit_val = true; // White (11)
else if (pixel_bits == 0x00) bit_val = false; // Black (00)
else if (pixel_bits == 0x02) bit_val = true; // Gray1 (10)
else if (pixel_bits == 0x01) bit_val = false; // Gray2 (01)
}
else
{
// OLD Layer (0x10) Mapping
if (pixel_bits == 0x03) bit_val = true; // White (11)
else if (pixel_bits == 0x00) bit_val = false; // Black (00)
else if (pixel_bits == 0x02) bit_val = false; // Gray1 (10)
else if (pixel_bits == 0x01) bit_val = true; // Gray2 (01)
}
if (bit_val) output_byte |= (1 << (7 - (j * 4 + k)));
}
}
g_scratch_buffer[scratch_idx++] = output_byte;
if (scratch_idx >= sizeof(g_scratch_buffer))
{
epd_write_buffer(g_scratch_buffer, scratch_idx);
scratch_idx = 0;
}
}
if (scratch_idx > 0)
{
epd_write_buffer(g_scratch_buffer, scratch_idx);
}
};
process_layer(0x10, false); // Old data
process_layer(0x13, true); // New data
ESP_LOGI(kTagEPD, "Data transmission complete (Refresh required)");
}