Fix: max buffer stored too long

Refs: #4

.gitignore

@@ -4,7 +4,6 @@ hardware/
 # compiler data
 build/
 src/.cache/
-src/.gdbinit
 src/compile_commands.json
 
 # local configs

src/main/esp32_eurorack_generic.c

@@ -1,6 +1,156 @@
 #include <stdio.h>
+#include <string.h>
+
+#include "esp_attr.h"
+#include "esp_err.h"
+#include "esp_log.h"
+#include "esp_adc/adc_cali.h"
+#include "esp_adc/adc_cali_scheme.h"
+#include "esp_adc/adc_continuous.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/portmacro.h"
+#include "hal/adc_types.h"
+#include "soc/soc_caps.h"
+
+/* ADC input pins */
+#define ADC_INPUT_1_PIN 4
+#define ADC_INPUT_2_PIN 6
+#define ADC_INPUT_3_PIN 9 /* TODO Reroute from pin 46 to 9 on schematic, cant do ADC */
+#define ADC_INPUT_4_PIN 10
+
+#define ADC_READ_LEN 16
+
+/* ADC channels */
+static adc_channel_t channel[4] = {ADC_CHANNEL_3, ADC_CHANNEL_5, ADC_CHANNEL_8, ADC_CHANNEL_9};
+
+/* ADC handles */
+static adc_continuous_handle_t adc_handle;
+static adc_cali_handle_t adc_cali_handle;
+static TaskHandle_t adc_task_handle;
+
+static const char *TAG = "EERG";
+
+/* ADC continuous read task */
+static void adc_read_task(void *pvParameter)
+{
+  ESP_LOGI(TAG, "Starting adc read task");
+  esp_err_t adc_ret;
+  uint32_t ret_num = 0;
+  uint8_t result[ADC_READ_LEN] = {0};
+  /* Fill result with 0xcc */
+  memset(result, 0xcc, ADC_READ_LEN);
+
+  while (1) {
+    /* Wait here until notified that the conversion is done */
+    ulTaskNotifyTake(pdTRUE, portMAX_DELAY);
+
+    /* Perform a read */
+    adc_ret = adc_continuous_read(adc_handle, result, ADC_READ_LEN, &ret_num, 0);
+    if (adc_ret == ESP_OK) {
+      ESP_LOGI("adc", "Got a reading");
+      for (int i = 0; i < ret_num; i+= SOC_ADC_DIGI_RESULT_BYTES) {
+        /* Grab the data and channel number */
+        adc_digi_output_data_t *p_data = (void*)&result[i];
+        uint32_t chan = ((p_data)->type2.channel);
+        uint32_t data = ((p_data)->type2.data);
+        /* Check channel number to see if data is bogus */
+        if (chan < SOC_ADC_CHANNEL_NUM(ADC_UNIT_1)) {
+          ESP_LOGI("adc", "ADC_1_%"PRIu32" value: %"PRIx32, chan, data);
+        } else {
+          ESP_LOGW("adc", "Invalid data from ADC_1_%"PRIu32, chan);
+        }
+      }
+    }
+    vTaskDelay(1000 / portTICK_PERIOD_MS);
+  }
+}
+
+/* ADC conversion finished callback */
+static bool IRAM_ATTR adc_conv_cb(adc_continuous_handle_t handle, const adc_continuous_evt_data_t *edata, void *user_data)
+{
+  BaseType_t mustYield = pdFALSE;
+  /* Send notification to handler task */
+  vTaskNotifyGiveFromISR(adc_task_handle, &mustYield);
+  return (mustYield == pdTRUE);
+}
+
+/* Deinitializes ADC handles */
+static void adc_cleanup(void)
+{
+  ESP_LOGI(TAG, "Cleaning up ADC");
+  ESP_ERROR_CHECK(adc_continuous_stop(adc_handle));
+  ESP_ERROR_CHECK(adc_continuous_deinit(adc_handle));
+  ESP_ERROR_CHECK(adc_cali_delete_scheme_curve_fitting(adc_cali_handle));
+}
+
+/* Initializes calibration driver of internal 12bit ADC */
+static void adc_cali_init(void)
+{
+  ESP_LOGI(TAG, "Initializing ADC calibration driver");
+  /* Create and apply calibration driver configuration */
+  adc_cali_curve_fitting_config_t cali_config = {
+    .unit_id = ADC_UNIT_1,
+    .atten = ADC_ATTEN_DB_0,
+    .bitwidth = ADC_BITWIDTH_DEFAULT
+  };
+  ESP_ERROR_CHECK(adc_cali_create_scheme_curve_fitting(&cali_config, &adc_cali_handle));
+}
+
+/* Initializes internal 12bit ADC */
+static void adc_cont_init(void)
+{
+  ESP_LOGI(TAG, "Initializing ADC continuous mode driver");
+
+  /* Create continuous mode driver handle */
+  adc_continuous_handle_cfg_t adc_handle_config = {
+    .max_store_buf_size = ADC_READ_LEN,
+    .conv_frame_size = ADC_READ_LEN
+  };
+  ESP_ERROR_CHECK(adc_continuous_new_handle(&adc_handle_config, &adc_handle));
+
+  /* Configure continuous driver */
+  adc_continuous_config_t adc_config = {
+    .sample_freq_hz = 20 * 1000, /* 20kHz TODO calculate proper sampling rate */
+    .conv_mode = ADC_CONV_SINGLE_UNIT_1,
+    .format = ADC_DIGI_OUTPUT_FORMAT_TYPE2,
+    .pattern_num = 4
+  };
+
+  /* Loop through channels for their configs */
+  adc_digi_pattern_config_t adc_pattern[4] = {0};
+  for (int i = 0; i < 4; i++){
+    adc_pattern[i].atten = ADC_ATTEN_DB_0;
+    adc_pattern[i].channel = channel[i];
+    adc_pattern[i].unit = ADC_UNIT_1;
+    adc_pattern[i].bit_width = ADC_BITWIDTH_12;
+  }
+  adc_config.adc_pattern = adc_pattern;
+  ESP_ERROR_CHECK(adc_continuous_config(adc_handle, & adc_config));
+
+  /* Configure callbacks */
+  adc_continuous_evt_cbs_t cbs = {
+    .on_conv_done = adc_conv_cb
+  };
+  ESP_ERROR_CHECK(adc_continuous_register_event_callbacks(adc_handle, &cbs, NULL));
+}
 
 void app_main(void)
 {
+  /* Initialize internal ADC */
+  /* Initialize calibration driver */
+  adc_cali_init();
+  /* Initialize continuous driver */
+  adc_cont_init();
+  /* Start the continuous driver */
+  ESP_ERROR_CHECK(adc_continuous_start(adc_handle));
 
+  xTaskCreate(adc_read_task, "adc read", 4096, NULL, 0, &adc_task_handle);
+
+  while (1) {
+
+  }
+
+  /* Cleanup ADC */
+  adc_cleanup();
 }