# ESP32 ESP-IDF component for LCD 1602A/1604A via I2C (PCF8574)

## Features

1. Support for HD44780-compatible 16x2 and 16x4 LCD displays via I2C.
2. 4-bit interface mode for efficient data transfer through PCF8574 expander.
3. Print strings, integers, and floating-point numbers to the display.
4. Progress bar display with custom characters on any row.
5. Cursor visibility and blink control.
6. Row-specific clear operations in addition to full screen clear.

## Attention

1. The PCF8574 expander handle must remain valid until the LCD handle is deinitialized.
2. DDRAM location 0xFF must be configured as a custom character in CGRAM for progress bar to display correctly.

## Using

In an existing project, run the following command to install the component:

```bash
cd ../your_project/components
git clone https://github.com/aZholtikov/zh_160x_i2c
```

In the application, add the component:

```c
#include "zh_160x_i2c.h"
```

## Examples

### Basic Text Output Example

```c
#include "zh_160x_i2c.h"

#define I2C_PORT (I2C_NUM_MAX - 1)

zh_pcf8574_handle_t *pcf8574_handle = NULL;
zh_160x_i2c_handle_t *lcd_handle = NULL;

void app_main(void)
{
    esp_log_level_set("zh_160x_i2c", ESP_LOG_ERROR);
    esp_log_level_set("zh_pcf8574", ESP_LOG_ERROR);
    i2c_master_bus_config_t i2c_bus_config = {
        .clk_source = I2C_CLK_SRC_DEFAULT,
        .i2c_port = I2C_PORT,
        .scl_io_num = GPIO_NUM_22,
        .sda_io_num = GPIO_NUM_21,
        .glitch_ignore_cnt = 7,
        .flags.enable_internal_pullup = true,
    };
    i2c_master_bus_handle_t i2c_bus_handle = NULL;
    esp_err_t ret = i2c_new_master_bus(&i2c_bus_config, &i2c_bus_handle);
    if (ret != ESP_OK)
    {
        printf("I2C bus initialization error\n");
        return;
    }
    zh_pcf8574_init_config_t pcf_config = ZH_PCF8574_INIT_CONFIG_DEFAULT();
    pcf_config.i2c_handle = i2c_bus_handle;
    pcf_config.i2c_address = 0x27;
    ret = zh_pcf8574_init(&pcf_config, &pcf8574_handle);
    if (ret != ESP_OK)
    {
        printf("PCF8574 initialization error\n");
        i2c_del_master_bus(i2c_bus_handle);
        return;
    }
    ret = zh_160x_init(&pcf8574_handle, &lcd_handle, ZH_LCD_16X2);
    if (ret != ESP_OK)
    {
        printf("LCD initialization error\n");
        zh_pcf8574_deinit(&pcf8574_handle);
        i2c_del_master_bus(i2c_bus_handle);
        return;
    }
    zh_160x_set_cursor(&lcd_handle, 0, 0);
    zh_160x_print_char(&lcd_handle, "LCD 160X");
    zh_160x_set_cursor(&lcd_handle, 1, 0);
    zh_160x_print_int(&lcd_handle, 42);
    zh_160x_off_cursor(&lcd_handle);
    zh_160x_deinit(&lcd_handle);
    zh_pcf8574_deinit(&pcf8574_handle);
    i2c_del_master_bus(i2c_bus_handle);
}
```

### Float and Cursor Control Example

```c
#include "zh_160x_i2c.h"

#define I2C_PORT (I2C_NUM_MAX - 1)

zh_pcf8574_handle_t *pcf8574_handle = NULL;
zh_160x_i2c_handle_t *lcd_handle = NULL;

void app_main(void)
{
    esp_log_level_set("zh_160x_i2c", ESP_LOG_ERROR);
    esp_log_level_set("zh_pcf8574", ESP_LOG_ERROR);
    i2c_master_bus_config_t i2c_bus_config = {
        .clk_source = I2C_CLK_SRC_DEFAULT,
        .i2c_port = I2C_PORT,
        .scl_io_num = GPIO_NUM_22,
        .sda_io_num = GPIO_NUM_21,
        .glitch_ignore_cnt = 7,
        .flags.enable_internal_pullup = true,
    };
    i2c_master_bus_handle_t i2c_bus_handle = NULL;
    esp_err_t ret = i2c_new_master_bus(&i2c_bus_config, &i2c_bus_handle);
    if (ret != ESP_OK)
    {
        printf("I2C bus initialization error\n");
        return;
    }
    zh_pcf8574_init_config_t pcf_config = ZH_PCF8574_INIT_CONFIG_DEFAULT();
    pcf_config.i2c_handle = i2c_bus_handle;
    pcf_config.i2c_address = 0x27;
    ret = zh_pcf8574_init(&pcf_config, &pcf8574_handle);
    if (ret != ESP_OK)
    {
        printf("PCF8574 initialization error\n");
        i2c_del_master_bus(i2c_bus_handle);
        return;
    }
    ret = zh_160x_init(&pcf8574_handle, &lcd_handle, ZH_LCD_16X2);
    if (ret != ESP_OK)
    {
        printf("LCD initialization error\n");
        zh_pcf8574_deinit(&pcf8574_handle);
        i2c_del_master_bus(i2c_bus_handle);
        return;
    }
    zh_160x_on_cursor(&lcd_handle, true);
    zh_160x_set_cursor(&lcd_handle, 0, 0);
    zh_160x_print_char(&lcd_handle, "Temp: ");
    zh_160x_print_float(&lcd_handle, 23.67f, 2);
    zh_160x_clear_row(&lcd_handle, 1);
    zh_160x_set_cursor(&lcd_handle, 1, 0);
    zh_160x_print_char(&lcd_handle, "Row cleared");
    zh_160x_off_cursor(&lcd_handle);
    zh_160x_deinit(&lcd_handle);
    zh_pcf8574_deinit(&pcf8574_handle);
    i2c_del_master_bus(i2c_bus_handle);
}
```

---

### Progress Bar Example

```c
#include "zh_160x_i2c.h"

#define I2C_PORT (I2C_NUM_MAX - 1)

zh_pcf8574_handle_t *pcf8574_handle = NULL;
zh_160x_i2c_handle_t *lcd_handle = NULL;

void app_main(void)
{
    esp_log_level_set("zh_160x_i2c", ESP_LOG_ERROR);
    esp_log_level_set("zh_pcf8574", ESP_LOG_ERROR);
    i2c_master_bus_config_t i2c_bus_config = {
        .clk_source = I2C_CLK_SRC_DEFAULT,
        .i2c_port = I2C_PORT,
        .scl_io_num = GPIO_NUM_22,
        .sda_io_num = GPIO_NUM_21,
        .glitch_ignore_cnt = 7,
        .flags.enable_internal_pullup = true,
    };
    i2c_master_bus_handle_t i2c_bus_handle = NULL;
    esp_err_t ret = i2c_new_master_bus(&i2c_bus_config, &i2c_bus_handle);
    if (ret != ESP_OK)
    {
        printf("I2C bus initialization error\n");
        return;
    }
    zh_pcf8574_init_config_t pcf_config = ZH_PCF8574_INIT_CONFIG_DEFAULT();
    pcf_config.i2c_handle = i2c_bus_handle;
    pcf_config.i2c_address = 0x27;
    ret = zh_pcf8574_init(&pcf_config, &pcf8574_handle);
    if (ret != ESP_OK)
    {
        printf("PCF8574 initialization error\n");
        i2c_del_master_bus(i2c_bus_handle);
        return;
    }
    ret = zh_160x_init(&pcf8574_handle, &lcd_handle, ZH_LCD_16X2);
    if (ret != ESP_OK)
    {
        printf("LCD initialization error\n");
        zh_pcf8574_deinit(&pcf8574_handle);
        i2c_del_master_bus(i2c_bus_handle);
        return;
    }
    zh_160x_set_cursor(&lcd_handle, 0, 0);
    zh_160x_print_char(&lcd_handle, "Progress: ");
    zh_160x_print_progress_bar(&lcd_handle, 1, 75);
    zh_160x_lcd_clear(&lcd_handle);
    zh_160x_deinit(&lcd_handle);
    zh_pcf8574_deinit(&pcf8574_handle);
    i2c_del_master_bus(i2c_bus_handle);
}
```