From b5de58469458c1f909cd76ce193f845aafe3a692 Mon Sep 17 00:00:00 2001
From: Tom Nordal <tnordal@gmail.com>
Date: Wed, 26 Jun 2024 22:15:11 +0200
Subject: [PATCH] lesson 61 moved

---
 lessons/lesson61.cpp | 102 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 102 insertions(+)
 create mode 100644 lessons/lesson61.cpp

diff --git a/lessons/lesson61.cpp b/lessons/lesson61.cpp
new file mode 100644
index 0000000..200d86b
--- /dev/null
+++ b/lessons/lesson61.cpp
@@ -0,0 +1,102 @@
+// Lesson 61. Ultrasonic Sensor with LCD Display
+// https://www.youtube.com/watch?v=nC2CDaqJomA
+
+
+#include <Arduino.h>
+#include <LiquidCrystal.h>
+
+const int rs = 7, en = 8, d4 = 9, d5 = 10, d6 = 11, d7 = 12;
+LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
+
+int trigPin = 2;
+int echoPin = 3;
+int pingTravleTime;
+float distance;
+const int pulsTime = 40;                // uS
+const float pingTimeToDistance = 0.017; // uS to cm, travletime[s] * 340 m/s / 2
+
+int numReadings = 50;
+float averageMeasurements;
+float averageTime;
+float bucketDist = 0.0;
+float bucketTime = 0.0;
+
+int buttonPin = A0;
+int buttomState;
+
+int setTime = 500;
+int dt = 1000;
+
+void setup()
+{
+  // put your setup code here, to run once:
+  Serial.begin(9600);
+  Serial.println("Measurring Distance");
+
+  delay(setTime);
+
+  lcd.begin(16, 2);
+  lcd.print("Hello, World!");
+
+  pinMode(trigPin, OUTPUT);
+  pinMode(echoPin, INPUT);
+  pinMode(buttonPin, INPUT);
+  digitalWrite(buttonPin, HIGH);
+}
+
+void loop()
+{
+  // put your main code here, to run repeatedly
+  buttomState = digitalRead(buttonPin);
+  while (buttomState == HIGH)
+  {
+    lcd.setCursor(0, 0);
+    lcd.print("Place the Target");
+    lcd.setCursor(0, 1);
+    lcd.print("Press the Button");
+    buttomState = digitalRead(buttonPin);
+  }
+
+  {
+    bucketDist = 0.0;
+    bucketTime = 0.0;
+
+    for (int i = 0; i < numReadings; i++)
+    {
+      digitalWrite(trigPin, LOW);
+      delayMicroseconds(pulsTime);
+      digitalWrite(trigPin, HIGH);
+      delayMicroseconds(pulsTime);
+      digitalWrite(trigPin, LOW);
+      pingTravleTime = pulseIn(echoPin, HIGH);
+      delay(25);
+
+      distance = pingTravleTime * pingTimeToDistance; // Travel time to distance in cm
+
+      bucketDist = bucketDist + distance;
+      bucketTime = bucketTime + pingTravleTime;
+
+    }
+
+    averageMeasurements = bucketDist / numReadings;
+    averageTime = bucketTime / numReadings;
+
+    Serial.print("Ping Time and Distance:");
+    Serial.print("Ping Time: ");
+    Serial.print(averageTime);
+    Serial.print(" Distance: ");
+    Serial.print(averageMeasurements);
+    Serial.println(" cm");
+
+    // Display on LCD
+    lcd.clear();
+    lcd.setCursor(0, 0);
+    lcd.print("Ping Time: ");
+    lcd.print(averageTime);
+    lcd.print("us");
+    lcd.setCursor(0, 1);
+    lcd.print("Distance: ");
+    lcd.print(averageMeasurements);
+    lcd.print("cm");
+  }
+}