From 89f5541124c89a010f9b9e30684ffd3acc4e3772 Mon Sep 17 00:00:00 2001
From: Joe Tretter <j.tretter@gmail.com>
Date: Sat, 17 Sep 2022 18:02:23 -0500
Subject: [PATCH] Add OLED Display

---
 platformio.ini |  4 ++--
 src/main.cpp   | 50 +++++++++++++++++++++++++++++++++++---------------
 2 files changed, 37 insertions(+), 17 deletions(-)

diff --git a/platformio.ini b/platformio.ini
index 7f472a9..5cdf289 100644
--- a/platformio.ini
+++ b/platformio.ini
@@ -14,5 +14,5 @@ board = esp32doit-devkit-v1
 framework = arduino
 lib_deps = 
 	ayushsharma82/AsyncElegantOTA@^2.2.7
-	#me-no-dev/ESP Async WebServer@^1.2.3
-    https://github.com/me-no-dev/ESPAsyncWebServer.git
+	https://github.com/me-no-dev/ESPAsyncWebServer.git
+	adafruit/Adafruit SSD1306@^2.5.7
diff --git a/src/main.cpp b/src/main.cpp
index 913560b..006e501 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,14 +1,9 @@
+#include <Adafruit_SSD1306.h>
 #include <Arduino.h>
-#if defined(ESP8266)
-#include <ESP8266WiFi.h>
-#include <ESPAsyncTCP.h>
-#elif defined(ESP32)
-#include <AsyncTCP.h>
-#include <WiFi.h>
-#endif
-
 #include <AsyncElegantOTA.h>
+#include <AsyncTCP.h>
 #include <ESPAsyncWebServer.h>
+#include <WiFi.h>
 
 const char* ssid = "JoNelsDarlings";
 const char* password = "Paris2016";
@@ -19,10 +14,36 @@ unsigned long lastMillis = millis();
 
 AsyncWebServer server(80);
 
+// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
+// I connected SCL to D22 and SDA to D21
+#define SCREEN_WIDTH 128  // OLED display width, in pixels
+#define SCREEN_HEIGHT 64  // OLED display height, in pixels
+
+Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);
+
+void writeToOled(String text) {
+  display.clearDisplay();
+  display.setTextColor(WHITE);
+  display.setCursor(0, 0);
+  display.setTextSize(2);
+  display.print(text);
+  display.display();
+}
+
 void setup(void) {
   pinMode(LED_BUILTIN, OUTPUT);
   digitalWrite(LED_BUILTIN, LOW);
-  Serial.begin(115200);
+  Serial.begin(9600);
+
+  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {  // Address 0x3D for 128x64
+    Serial.println(F("SSD1306 allocation failed"));
+    for (;;)
+      ;
+  }
+  delay(2000);
+
+  writeToOled("Startup");
+
   WiFi.mode(WIFI_STA);
   WiFi.begin(ssid, password);
   Serial.println("");
@@ -54,22 +75,21 @@ void setup(void) {
   server.begin();
   Serial.println("HTTP server started");
 
-  pinMode(BUBBLE_GPIO, INPUT_PULLDOWN);
-  digitalWrite(LED_BUILTIN, HIGH);
+  pinMode(BUBBLE_GPIO, INPUT_PULLUP);
 }
 
 void loop(void) {
-  // digitalWrite(LED_BUILTIN, digitalRead(BUBBLE_GPIO));
+  digitalWrite(LED_BUILTIN, digitalRead(BUBBLE_GPIO));
 
   // This runs real fast, so make sure that only the "first contact" is measured
-  if ((digitalRead(BUBBLE_GPIO) == HIGH) && isBubbleFirstContact) {
-    digitalWrite(LED_BUILTIN, LOW);
+  if ((digitalRead(BUBBLE_GPIO) == LOW) && isBubbleFirstContact) {
     if (millis() > lastMillis) {  // don't measure if we had an overflow...
       bubbleFreqSec = (millis() - lastMillis) / 1000;
+      writeToOled("Freq: " + String(bubbleFreqSec));
     }
     lastMillis = millis();
     isBubbleFirstContact = false;
-  } else if ((digitalRead(BUBBLE_GPIO) == LOW)) {
+  } else if ((digitalRead(BUBBLE_GPIO) == HIGH)) {
     isBubbleFirstContact = true;
   }