From c9a379eaae0ed4806abb504b67b321a5944a8edc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Patrick=20Ha=C3=9Fel?= <git@patrick-hassel.de>
Date: Mon, 17 Feb 2025 20:08:17 +0100
Subject: [PATCH] Fermenter display

---
 src/Fermenter.cpp | 47 ++++++++++++++++++++++++++++++++---------------
 1 file changed, 32 insertions(+), 15 deletions(-)

diff --git a/src/Fermenter.cpp b/src/Fermenter.cpp
index f1bc03c..250118e 100644
--- a/src/Fermenter.cpp
+++ b/src/Fermenter.cpp
@@ -16,34 +16,50 @@ DS18B20 ds18b20("DS18B20", D4);
 
 DS18B20Sensor input(ds18b20, 0, "");
 
-PWMOutput heater(D2, "");
+PWMOutput heater(D2, "", 100);
 
 PIDController pid("fermenter", input, heater, UNIT_TEMPERATURE_C, 500, 0.00000002, 0);
 
+auto displayToggleInterval = 2000UL;
+
 auto display = LedControl(13, 14, 15, 1);
 
-void displayDecimal(int *digit, const double value) {
-  const auto integer = static_cast<int>(value);
-  const auto decimal = static_cast<int>((value - integer) * 10) % 10;
-  display.setDigit(0, (*digit)++, decimal, false);
-  display.setDigit(0, (*digit)++, integer % 10, true);
-  display.setDigit(0, (*digit)++, integer / 10 % 10, false);
+void displayPrintf(const char *format, ...) {
+  va_list args;
+  va_start(args, format);
+  char buffer[9];
+  vsnprintf(buffer, sizeof buffer, format, args);
+  int position = 0;
+  for (char *b = buffer; *b != 0 && b < buffer + sizeof buffer; b++) {
+    display.setChar(0, position++, *b, false);
+  }
+  va_end(args);
 }
 
 void displayLoop() {
-  static unsigned long lastDisplayInit = 0;
-  if (lastDisplayInit == 0 || millis() - lastDisplayInit > 60 * 60 * 1000) {
-    lastDisplayInit = millis();
+  const auto now = millis();
+
+  static unsigned long lastInit = 0;
+  if (lastInit == 0 || now - lastInit >= 60 * 60 * 1000) {
+    lastInit = now;
     display.shutdown(0, true);
     display.shutdown(0, false);
     display.setIntensity(0, 4);
     display.clearDisplay(0);
   }
-  auto digit = 0;
-  displayDecimal(&digit, input.getValue());
-  digit++;
-  digit++;
-  displayDecimal(&digit, pid.targetValue);
+
+  static auto mode = true;
+  static auto lastMode = 0UL;
+  if (lastMode == 0 || now - lastMode >= displayToggleInterval) {
+    lastMode = now;
+    mode = !mode;
+  }
+
+  if (mode) {
+    displayPrintf("%3.0f     ", heater.getPercent());
+  } else {
+    displayPrintf("%-4.1f%4.1f", input.getValue(), pid.targetValue);
+  }
 }
 
 void httpStatus(AsyncWebServerRequest *request) {
@@ -111,6 +127,7 @@ void patrixLoop() {
   ds18b20.loop();
   input.loop();
   pid.loop();
+  displayLoop();
 }
 
 #endif