LED display

platformio.ini

@@ -15,6 +15,7 @@ lib_deps = https://github.com/milesburton/Arduino-Temperature-Control-Library
            bblanchon/ArduinoJson
            Wire
            https://github.com/phassel/ArduPID/
+           https://github.com/wayoda/LedControl
 
 [env:TEST32]
 upload_port = 10.42.0.66

src/Fermenter.cpp

@@ -7,6 +7,7 @@
 #include "config.h"
 #include "console.h"
 #include <Arduino.h>
+#include "LedControl.h"
 
 #define SENSOR_GPIO           D4
 #define CONTROL_GPIO          D2
@@ -25,6 +26,8 @@ DallasSensor sensor(dallas, 0x3D0417C1D740FF28, "temperatur.ist", 0.1, 5, 60 * 1
 
 ArduPID pid;
 
+LedControl lc = LedControl(13, 14, 15, 1);
+
 double proportional = PID_DEFAULT_P;
 
 double integral = PID_DEFAULT_I;
@@ -39,6 +42,10 @@ double temperatureCurrent = NAN;
 
 double heaterPWM = 0;
 
+void writeDecimal(int *digit, double value);
+
+void displayLoop();
+
 void patrixSetup() {
   dallas.begin();
   analogWriteResolution(CONTROL_PWM_BITS);
@@ -54,6 +61,8 @@ void patrixLoop() {
   dallas.loop();
   sensor.loop();
 
+  displayLoop();
+
   temperatureCurrent = sensor.getLastValue();
   if (!isnan(temperatureCurrent)) {
     pid.compute();
@@ -89,6 +98,31 @@ void patrixLoop() {
   }
 }
 
+
+void displayLoop() {
+  static unsigned long lastDisplayInit = 0;
+  if (lastDisplayInit == 0 || millis() - lastDisplayInit > 60 * 60 * 1000) {
+    lastDisplayInit = millis();
+    lc.shutdown(0, true);
+    lc.shutdown(0, false);
+    lc.setIntensity(0, 4);
+    lc.clearDisplay(0);
+  }
+  int digit = 0;
+  writeDecimal(&digit, temperatureCurrent);
+  digit++;
+  digit++;
+  writeDecimal(&digit, temperatureTarget);
+}
+
+void writeDecimal(int *digit, double value) {
+  const int integer = (int) value;
+  const int decimal = (int) ((value - integer) * 10) % 10;
+  lc.setDigit(0, (*digit)++, decimal, false);
+  lc.setDigit(0, (*digit)++, integer % 10, true);
+  lc.setDigit(0, (*digit)++, integer / 10 % 10, false);
+}
+
 bool setDouble(const char *name, double *destinationPtr, double min, double max) {
   const char *valueStr = strtok(nullptr, "");
   if (valueStr == nullptr) {