pcnt: add rotary encoder example

examples/peripherals/pcnt/rotary_encoder/main/CMakeLists.txt

@@ -0,0 +1,2 @@
+idf_component_register(SRCS "rotary_encoder_example_main.c"
+                       INCLUDE_DIRS ".")

examples/peripherals/pcnt/rotary_encoder/main/component.mk

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+#
+# Main Makefile. This is basically the same as a component makefile.
+#

examples/peripherals/pcnt/rotary_encoder/main/rotary_encoder_example_main.c

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+/* PCNT example -- Rotary Encoder
+
+   This example code is in the Public Domain (or CC0 licensed, at your option.)
+
+   Unless required by applicable law or agreed to in writing, this
+   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
+   CONDITIONS OF ANY KIND, either express or implied.
+*/
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "esp_log.h"
+#include "rotary_encoder.h"
+
+static const char *TAG = "example";
+
+void app_main(void)
+{
+    // Rotary encoder underlying device is represented by a PCNT unit in this example
+    uint32_t pcnt_unit = 0;
+
+    // Create rotary encoder instance
+    rotary_encoder_config_t config = ROTARY_ENCODER_DEFAULT_CONFIG((rotary_encoder_dev_t)pcnt_unit, 14, 15);
+    rotary_encoder_t *encoder = NULL;
+    ESP_ERROR_CHECK(rotary_encoder_new_ec11(&config, &encoder));
+
+    // Filter out glitch (1us)
+    ESP_ERROR_CHECK(encoder->set_glitch_filter(encoder, 1));
+
+    // Start encoder
+    ESP_ERROR_CHECK(encoder->start(encoder));
+
+    // Report counter value
+    while (1) {
+        ESP_LOGI(TAG, "Encoder value: %d", encoder->get_counter_value(encoder));
+        vTaskDelay(pdMS_TO_TICKS(1000));
+    }
+}