From 58702666f220ecabe00c7c4d6e54b04d0f956bb5 Mon Sep 17 00:00:00 2001
From: rkcf <rkcf@rkcf.me>
Date: Tue, 7 Feb 2023 17:05:15 -0600
Subject: [PATCH] Add: main rotary encoder c file with basic counting

---
 main/esp32_rgb_rotary_encoder.c | 101 ++++++++++++++++++++++++++++++++
 1 file changed, 101 insertions(+)
 create mode 100644 main/esp32_rgb_rotary_encoder.c

diff --git a/main/esp32_rgb_rotary_encoder.c b/main/esp32_rgb_rotary_encoder.c
new file mode 100644
index 0000000..50fc7c4
--- /dev/null
+++ b/main/esp32_rgb_rotary_encoder.c
@@ -0,0 +1,101 @@
+#include <stdio.h>
+
+#include "esp_err.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/portmacro.h"
+#include "freertos/projdefs.h"
+#include "freertos/task.h"
+#include "freertos/queue.h"
+#include "esp_log.h"
+#include "driver/pulse_cnt.h"
+#include "hal/pcnt_types.h"
+
+/* Pinouts */
+#define PCNT_A_PIN 1 /* Rotary Encoder A Pin */
+#define PCNT_B_PIN 2 /* Rotary Encoder B Pin */
+
+/* Pulse Count Settings */
+#define PCNT_HIGH_LIMIT 100
+#define PCNT_LOW_LIMIT -100
+
+static QueueHandle_t pcnt_queue = NULL;
+
+static const char *TAG = "RE Demo"; /* logging tag */
+
+/* Pulse Counter Callback */
+static bool pcnt_cb(pcnt_unit_handle_t unit, const pcnt_watch_event_data_t *edata, void *user_ctx) {
+  BaseType_t high_task_wakeup;
+  /* Put the watchpoint value in a queue to be handled later */
+  xQueueSendFromISR(pcnt_queue, &(edata->watch_point_value), &high_task_wakeup);
+  return (high_task_wakeup == pdTRUE);
+}
+
+/* Main Loop */
+void app_main(void){
+
+  /* Configure the PCNT unit and get a handle */
+  ESP_LOGI(TAG, "Setting up Pulse Counter Unit");
+  pcnt_unit_config_t pcnt_unit_config = {
+    .high_limit = PCNT_HIGH_LIMIT,
+    .low_limit = PCNT_LOW_LIMIT
+  };
+  pcnt_unit_handle_t pcnt_unit = NULL;
+  ESP_ERROR_CHECK(pcnt_new_unit(&pcnt_unit_config, &pcnt_unit));
+
+  /* Configure PCNT A & B channels and get handles */
+  ESP_LOGI(TAG, "Setting up Pulse Counter Channels");
+  pcnt_chan_config_t pcnt_chan_a_config = {
+    .edge_gpio_num = PCNT_A_PIN,
+    .level_gpio_num = PCNT_B_PIN
+  };
+  pcnt_channel_handle_t pcnt_chan_a = NULL;
+  ESP_ERROR_CHECK(pcnt_new_channel(pcnt_unit, &pcnt_chan_a_config, &pcnt_chan_a));
+
+  pcnt_chan_config_t pcnt_chan_b_config = {
+    .edge_gpio_num = PCNT_B_PIN,
+    .level_gpio_num = PCNT_A_PIN
+  };
+  pcnt_channel_handle_t pcnt_chan_b = NULL;
+  ESP_ERROR_CHECK(pcnt_new_channel(pcnt_unit, &pcnt_chan_b_config, &pcnt_chan_b));
+
+  /* Configure edge/level actions on channels */
+  ESP_ERROR_CHECK(pcnt_channel_set_edge_action(pcnt_chan_a, PCNT_CHANNEL_EDGE_ACTION_DECREASE, PCNT_CHANNEL_EDGE_ACTION_INCREASE));
+  ESP_ERROR_CHECK(pcnt_channel_set_level_action(pcnt_chan_a, PCNT_CHANNEL_LEVEL_ACTION_KEEP, PCNT_CHANNEL_LEVEL_ACTION_INVERSE));
+  ESP_ERROR_CHECK(pcnt_channel_set_edge_action(pcnt_chan_b, PCNT_CHANNEL_EDGE_ACTION_INCREASE, PCNT_CHANNEL_EDGE_ACTION_DECREASE));
+  ESP_ERROR_CHECK(pcnt_channel_set_level_action(pcnt_chan_b, PCNT_CHANNEL_LEVEL_ACTION_KEEP, PCNT_CHANNEL_LEVEL_ACTION_INVERSE));
+
+  /* Install watch points */
+  ESP_LOGI(TAG, "Installing watch points and callback handler");
+  int watch_points[] = {PCNT_LOW_LIMIT, -50, 0, 50, PCNT_HIGH_LIMIT};
+  for (size_t i = 0; i < sizeof(watch_points) / sizeof(watch_points[0]); i++) {
+    ESP_ERROR_CHECK(pcnt_unit_add_watch_point(pcnt_unit, watch_points[i]));
+  }
+
+  /* Initialize pcnt event queue */
+  pcnt_queue = xQueueCreate(10, sizeof(int));
+
+  /* Install callback */
+  pcnt_event_callbacks_t cbs = {
+    .on_reach = pcnt_cb
+  };
+  ESP_ERROR_CHECK(pcnt_unit_register_event_callbacks(pcnt_unit, &cbs, NULL));
+
+  /* Enable, clear, and start pcnt Unit */
+  ESP_LOGI(TAG, "Starting Pulse Counter");
+  ESP_ERROR_CHECK(pcnt_unit_enable(pcnt_unit));
+  ESP_ERROR_CHECK(pcnt_unit_clear_count(pcnt_unit));
+  ESP_ERROR_CHECK(pcnt_unit_start(pcnt_unit));
+
+  /* Log counter value */
+  int pulse_count = 0;
+  int event_count = 0;
+
+  while (1) {
+    if (xQueueReceive(pcnt_queue, &event_count, pdMS_TO_TICKS(1000))) {
+      ESP_LOGI(TAG, "Watch point event, count: %d", event_count);
+    } else {
+      ESP_ERROR_CHECK(pcnt_unit_get_count(pcnt_unit, &pulse_count));
+      ESP_LOGI(TAG, "Pulse count: %d", pulse_count);
+    }
+  }
+}