feat!: main structure of handle changed to double pointer

README.md

@@ -1,20 +1,22 @@
 # ESP32 ESP-IDF component for tachometer (via rotary optical encoder)
 
-## Tested on
-
-1. [ESP32 ESP-IDF v6.0.0](https://docs.espressif.com/projects/esp-idf/en/v6.0/esp32/index.html)
-
 ## SAST Tools
 
 [PVS-Studio](https://pvs-studio.com/pvs-studio/?utm_source=website&utm_medium=github&utm_campaign=open_source) - static analyzer for C, C++, C#, and Java code.
 
 ## Features
 
-1. Support up to 8 tachometers on one device.
+1. Quadrature encoder support via ESP-IDF PCNT peripheral in quadrature decoder mode.
+2. Automatic RPM calculation based on configurable pulses-per-revolution.
+3. Periodic RPM sampling via ESP-Timer at 100 Hz (10 ms interval).
+4. Configurable GPIO pull-up resistors for encoder A/B phases.
+5. PCNT glitch filter (1000 ns) to reject spurious transitions.
+6. Watch points at ±32767 for overflow detection.
+7. Multiple tachometers supported — each requires its own PCNT unit and timer.
 
-## Attention
+## Note
 
-1. For correct operation, please enable the following settings in the menuconfig:
+Enable the following settings in menuconfig:
 
 ```text
 PCNT_CTRL_FUNC_IN_IRAM
@@ -25,7 +27,7 @@ PCNT_ISR_IRAM_SAF
 
 In an existing project, run the following command to install the components:
 
-```text
+```bash
 cd ../your_project/components
 git clone https://github.com/aZholtikov/zh_tachometer
 ```
@@ -36,27 +38,37 @@ In the application, add the component:
 #include "zh_tachometer.h"
 ```
 
-## Examples
+## Example
 
 ```c
 #include "zh_tachometer.h"
 
-zh_tachometer_handle_t tachometer_handle = {0};
+static zh_tachometer_handle_t *tachometer_handle = NULL;
 
 void app_main(void)
 {
     esp_log_level_set("zh_tachometer", ESP_LOG_ERROR);
+
     zh_tachometer_init_config_t config = ZH_TACHOMETER_INIT_CONFIG_DEFAULT();
     config.a_gpio_number = GPIO_NUM_26;
     config.b_gpio_number = GPIO_NUM_27;
     config.encoder_pulses = 3600;
-    zh_tachometer_init(&config, &tachometer_handle);
-    for (;;)
-    {
-        uint16_t value = 0;
-        zh_tachometer_get(&tachometer_handle, &value);
-        printf("Tachometer value is %d rpm.\n", value);
+
+    esp_err_t ret = zh_tachometer_init(&config, &tachometer_handle);
+    if (ret != ESP_OK) {
+        ESP_LOG_ERROR("zh_tachometer", "Initialization failed: %s", esp_err_to_name(ret));
+        return;
+    }
+
+    for (;;) {
+        uint16_t rpm = 0;
+        ret = zh_tachometer_get(&tachometer_handle, &rpm);
+        if (ret == ESP_OK) {
+            printf("Tachometer value is %d rpm.\n", rpm);
+        }
         vTaskDelay(100 / portTICK_PERIOD_MS);
     }
+
+    zh_tachometer_deinit(&tachometer_handle);
 }
 ```