From 22842dfc708185f00ad64d909a3577f5aee53843 Mon Sep 17 00:00:00 2001
From: Chris Giacofei <c.giacofei@gmail.com>
Date: Fri, 14 Jan 2022 08:23:51 -0500
Subject: [PATCH] Turn slowPWM into a class.

Slightly cleaner looking this way.
---
 boil_kettle/boil_kettle.ino | 15 +++++++-------
 boil_kettle/slowPWM.h       | 41 +++++++++++++++++++++++++++++++++++++
 boil_kettle/slowPWM.ino     | 27 ------------------------
 3 files changed, 48 insertions(+), 35 deletions(-)
 create mode 100644 boil_kettle/slowPWM.h
 delete mode 100644 boil_kettle/slowPWM.ino

diff --git a/boil_kettle/boil_kettle.ino b/boil_kettle/boil_kettle.ino
index 2597925..373805b 100644
--- a/boil_kettle/boil_kettle.ino
+++ b/boil_kettle/boil_kettle.ino
@@ -15,6 +15,7 @@
 // My Includes
 #include "config.h"
 #include "button.h"
+#include "slowPWM.h"
 
 // Pin definitions
 #define encoderCLK 2
@@ -28,12 +29,10 @@ bool KettleOn = false;
 
 // User I/O objects.
 Button Enter;
+slowPWM boilPWM;
 MD_REncoder rotary = MD_REncoder(encoderDT, encoderCLK);
 LiquidCrystal_I2C lcd(0x27,20,4);
 
-float output = 0;
-int updateInterval = 1000;
-
 EthernetClient net;
 MQTTClient mqtt_client;
 
@@ -76,7 +75,7 @@ LiquidMenu menu(lcd);
 
 void setup() {
 
-  unsigned long lastRun = millis() - updateInterval;
+  unsigned long lastRun = millis() - UpdateInterval;
   Serial.begin(9600);
   rotary.begin();
   Ethernet.begin(mac, ip);
@@ -88,7 +87,7 @@ void setup() {
   pinMode(encoderCLK, INPUT_PULLUP);
   pinMode(encoderDT, INPUT_PULLUP);
   Enter.begin(encoderBTN);
-  pinMode(encoderBTN, INPUT_PULLUP);
+  boilPWM.begin(kettlePWM, PeriodPWM);
 
   // if you get a connection, report back via serial:
   if (Ethernet.linkStatus() == LinkON) {
@@ -121,9 +120,9 @@ void UpdateBoilKettle(){
   }
 
   if (KettleOn) {
-    slowPWM(kettlePWM, KettleDuty, PeriodPWM);
+    boilPWM.compute(KettleDuty);
   } else {
-    slowPWM(kettlePWM, 0, PeriodPWM);
+    boilPWM.compute(0);
   }
 }
 
@@ -132,7 +131,7 @@ void loop() {
 
   unsigned long elapsedTime = (millis() - lastRun);
 
-  if (elapsedTime >= updateInterval) {
+  if (elapsedTime >= UpdateInterval) {
     mqtt_client.loop();
     //if (!mqtt_client.connected()) ConnectMQTT();
 
diff --git a/boil_kettle/slowPWM.h b/boil_kettle/slowPWM.h
new file mode 100644
index 0000000..93614cc
--- /dev/null
+++ b/boil_kettle/slowPWM.h
@@ -0,0 +1,41 @@
+#ifndef SLOWPWM_h
+#define SLOWPWM_h
+
+#include <Arduino.h>
+
+class slowPWM {
+  private:
+    byte outputPin;
+    byte dutyCycle;
+    unsigned long period;
+    unsigned long lastSwitchTime;
+    byte outputState;
+
+  public:
+    void begin(byte pin, unsigned long per) {
+      outputPin = pin;
+      period = per;
+      lastSwitchTime = 0;
+      outputState = LOW;
+      pinMode(pin, OUTPUT);
+    }
+
+    void compute(byte duty) {
+      unsigned long onTime = (dutyCycle * period) / 100;
+      unsigned long offTime = period - onTime;
+      unsigned long currentTime = millis();
+
+      if (outputState == HIGH && (currentTime - lastSwitchTime >= onTime))
+      {
+        lastSwitchTime = currentTime;
+        outputState = LOW;
+      }
+      if (outputState == LOW && (currentTime - lastSwitchTime >= offTime))
+      {
+        lastSwitchTime = currentTime;
+        outputState = HIGH;
+      }
+      digitalWrite(outputPin, outputState);
+    }
+};
+#endif
diff --git a/boil_kettle/slowPWM.ino b/boil_kettle/slowPWM.ino
deleted file mode 100644
index acf5eb9..0000000
--- a/boil_kettle/slowPWM.ino
+++ /dev/null
@@ -1,27 +0,0 @@
-// Bit bang low frequency PWM.
-//
-// Parameters:
-// outputPin (byte)       - Pin number to output PWM.
-// dutyCycle (byte)       - PWM period from 0 - 100.
-void slowPWM(byte outputPin, byte dutyCycle, unsigned long period)
-{
-  static byte outputState = LOW;
-  static unsigned long lastSwitchTime = 0;
-
-  unsigned long onTime = (dutyCycle * period) / 100;
-  unsigned long offTime = period - onTime;
-
-  unsigned long currentTime = millis();
-
-  if (outputState == HIGH && (currentTime - lastSwitchTime >= onTime))
-  {
-    lastSwitchTime = currentTime;
-    outputState = LOW;
-  }
-  if (outputState == LOW && (currentTime - lastSwitchTime >= offTime))
-  {
-    lastSwitchTime = currentTime;
-    outputState = HIGH;
-  }
-  digitalWrite(outputPin, outputState);
-}