pt100 temp sensing

main/CMakeLists.txt

@@ -1,4 +1,4 @@
-set(COMPONENT_SRCS "app_main.c" "nokia.c" "knob.c" "gui.c")
+set(COMPONENT_SRCS "app_main.c" "nokia.c" "knob.c" "gui.c" "analog.c")
 set(COMPONENT_ADD_INCLUDEDIRS "")
 
 register_component()

main/analog.c

@@ -0,0 +1,72 @@
+#include <stdint.h>
+#include <stdatomic.h>
+#include "analog.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "driver/gpio.h"
+#include "driver/adc.h"
+#include "esp_adc_cal.h"
+
+static esp_adc_cal_characteristics_t *adc_chars;
+
+// 32-39
+static const adc1_channel_t channel = ADC1_CHANNEL_4;     //GPIO34 if ADC1, GPIO14 if ADC2
+
+static float measurement_celsius;
+static const adc_atten_t atten = ADC_ATTEN_DB_0;
+static const adc_unit_t unit = ADC_UNIT_1;
+
+static void analog_service(void *arg);
+
+static TaskHandle_t hAnalog;
+
+#define DEFAULT_VREF 1100
+#define NO_OF_SAMPLES 64
+
+void analog_init() {
+    printf("Analog init\n");
+
+    adc1_config_width(ADC_WIDTH_BIT_12);
+    adc1_config_channel_atten(channel, atten);
+    adc_chars = calloc(1, sizeof(esp_adc_cal_characteristics_t));
+    esp_adc_cal_characterize(unit, atten, ADC_WIDTH_BIT_12, DEFAULT_VREF, adc_chars);
+
+    int rv = xTaskCreate(analog_service, "analog", 4096, NULL, 6, &hAnalog);
+    assert (rv == pdPASS);
+}
+
+
+static void __attribute__((noreturn)) analog_service(void *arg) {
+    while (1) {
+        uint32_t adc_reading = 0;
+        //Multisampling
+        for (int i = 0; i < NO_OF_SAMPLES; i++) {
+            adc_reading += adc1_get_raw(channel);
+        }
+        adc_reading /= NO_OF_SAMPLES;
+
+        //Convert adc_reading to voltage in mV
+        uint32_t voltage = esp_adc_cal_raw_to_voltage(adc_reading, adc_chars);
+
+#define CORRECT -10;
+        voltage += CORRECT;
+
+//        printf("Raw: %d ... Voltage: %dmV ...", adc_reading, voltage);
+
+        float volts = voltage * 0.001f;
+
+#define R1 4750
+#define V1 3.3f
+        float r_pt100 = (volts * R1)/(V1 - volts);
+        float celsius = (r_pt100/100.0f - 1.0f) / 3.9083E-3f;
+//        printf("Rpt %.3f, Celsius: %.1f\n", r_pt100, celsius);
+
+        measurement_celsius = celsius;
+
+        vTaskDelay(pdMS_TO_TICKS(100));
+    }
+}
+
+float analog_read() {
+    return measurement_celsius;
+}

main/analog.h

@@ -0,0 +1,14 @@
+/**
+ * TODO file description
+ * 
+ * Created on 2020/01/03.
+ */
+
+#ifndef REFLOWER_ANALOG_H
+#define REFLOWER_ANALOG_H
+
+void analog_init();
+
+float analog_read();
+
+#endif //REFLOWER_ANALOG_H

main/app_main.c

@@ -14,6 +14,7 @@
 #include "nokia.h"
 #include "knob.h"
 #include "gui.h"
+#include "analog.h"
 
 
 void __attribute__((noreturn)) app_main()
@@ -28,8 +29,8 @@ void __attribute__((noreturn)) app_main()
 
 
     gui_init();
-
     knob_init();
+    analog_init();
 
     bool level = 0;
     while (1) {

main/gui.c

@@ -1,5 +1,6 @@
 #include "gui.h"
 #include "nokia.h"
+#include "analog.h"
 #include <freertos/FreeRTOS.h>
 #include <freertos/task.h>
 
@@ -32,12 +33,15 @@ void gui_init() {
  * @param arg
  */
 static void __attribute__((noreturn)) gui_thread(void *arg) {
-    uint32_t pos = 20;
+    uint32_t pos = 0;
     bool btn = 0;
+
+    uint32_t last_wheel_time = 0;
 #define NMAX 60
     while (1) {
         uint32_t value = 0;
-        xTaskNotifyWait(0, ULONG_MAX, &value, portMAX_DELAY);
+        xTaskNotifyWait(0, ULONG_MAX, &value, pdMS_TO_TICKS(250));
+
 //        printf("Knob event 0x%02x  ", value);
 
         if (value & 0b1000) {
@@ -47,23 +51,27 @@ static void __attribute__((noreturn)) gui_thread(void *arg) {
             btn = 0;
         }
 
-        if (value & 0b01) {
-//            printf("FWD  ");
-            if (pos == NMAX) {
-                pos = 0;
-            }
-            else {
-                pos += 1;
+        if (value & 0b11) {
+            uint32_t time = xTaskGetTickCount();
+            uint32_t increment = 1;
+            if (last_wheel_time != 0) {
+                uint32_t ela = time - last_wheel_time;
+                if (ela < pdMS_TO_TICKS(20)) {
+                    increment = 25;
+                } else if (ela < pdMS_TO_TICKS(35)) {
+                    increment = 10;
+                } else if (ela < pdMS_TO_TICKS(75)) {
+                    increment = 5;
+                }
             }
-        }
+            last_wheel_time = time;
 
-        if (value & 0b10) {
-//            printf("BACK ");
-            if (pos == 0) {
-                pos = NMAX;
+            if (value & 0b01) {
+                pos += increment;
             }
-            else {
-                pos--;
+
+            if (value & 0b10) {
+                pos -= increment;
             }
         }
 
@@ -71,6 +79,8 @@ static void __attribute__((noreturn)) gui_thread(void *arg) {
         char buf[10];
         sprintf(buf, "%3d %s", pos, btn?"BTN":"");
         LCD_setStr(buf, 2, 17, 0);
+        sprintf(buf, "%.0f C", analog_read());
+        LCD_setStr(buf, 2, 26, 0);
         LCD_updateDisplay();
 
 //        printf(">");