From 8f3b33041aa1f879390080dfff5a5304e06773f7 Mon Sep 17 00:00:00 2001
From: Ryan Hartje <hartjepc@gmail.com>
Date: Sat, 9 Sep 2023 13:30:55 -0500
Subject: [PATCH] Update audio.md

Resolve syntax errors, seems like potentially a linter or formatted tried to escape asterisks, and in cases of variable assignment, changed them to underscores, breaking the code.

Validated here:
https://wokwi.com/projects/375416657031917569

See also a very similarly updated example here:
https://projecthub.arduino.cc/rowan07/rickroll-piezo-buzzer-b3d9fd
---
 .../learn/03.programming/10.audio/audio.md    | 161 +++++++++---------
 1 file changed, 81 insertions(+), 80 deletions(-)

diff --git a/content/learn/03.programming/10.audio/audio.md b/content/learn/03.programming/10.audio/audio.md
index e61d3df697..196c859368 100644
--- a/content/learn/03.programming/10.audio/audio.md
+++ b/content/learn/03.programming/10.audio/audio.md
@@ -960,7 +960,7 @@ The following example was created by Samantha Lagestee in 2017. Inspired by the
 
 ```
 
-/\* Rick Roll Code
+/* Rick Roll Code
 AUTHOR: Samantha Lagestee
 Copyright 2017 samilagestee at gmail dot com
 
@@ -973,7 +973,7 @@ Copyright 2017 samilagestee at gmail dot com
     is not the creative property of the author. This code simply
     plays a Piezo buzzer rendition of the song.
 
-\*/
+*/
 
 #define a3f 208 // 208 Hz
 #define b3f 233 // 233 Hz
@@ -1068,7 +1068,7 @@ int song1_chorus_rhythmn[] =
 3, 3, 3, 1, 2, 2, 2, 4, 8, 4
 };
 
-char\* lyrics_chorus[] =
+char* lyrics_chorus[] =
 { "Never ", "", "gonna ", "", "give ", "you ", "up\r\n",
 "Never ", "", "gonna ", "", "let ", "you ", "down", "", "\r\n",
 "Never ", "", "gonna ", "", "run ", "around ", "", "", "", "and ", "desert ", "", "you\r\n",
@@ -1079,90 +1079,91 @@ char\* lyrics_chorus[] =
 
 void setup()
 {
-pinMode(piezo, OUTPUT);
-pinMode(led, OUTPUT);
-digitalWrite(led, LOW);
-Serial.begin(9600);
-flag = true;
-a = 4;
-b = 0;
-c = 0;
+  pinMode(piezo, OUTPUT);
+  pinMode(led, OUTPUT);
+  digitalWrite(led, LOW);
+  Serial.begin(9600);
+  flag = true;
+  a = 4;
+  b = 0;
+  c = 0;
 }
 
 void loop()
 {
-// edit code here to define play conditions
-/_
-if (CONDITION 1) { // play
-flag = true;
-}
-else if (CONDITION2) { // pause
-flag = false;
-}
-_/
-
-// play next step in song
-if (flag == true) {
-play();
-}
+  // edit code here to define play conditions
+  /*
+  if (CONDITION 1) { // play
+    flag = true;
+  }
+  else if (CONDITION2) { // pause
+    flag = false;
+  }
+  */
+  
+  // play next step in song
+  if (flag == true) {
+    play();
+  }
 }
 
 void play() {
-int notelength;
-if (a == 1 || a == 2) { // Intro
-// intro
-notelength = beatlength _ song1_intro_rhythmn[b];
-if (song1_intro_melody[b] > 0) { // if not a rest, play note
-digitalWrite(led, HIGH);
-tone(piezo, song1_intro_melody[b], notelength);
-}
-b++;
-if (b >= sizeof(song1_intro_melody) / sizeof(int)) {
-a++;
-b = 0;
-c = 0;
-}
-}
-else if (a == 3 || a == 5) { // Verse 1
-// verse
-notelength = beatlength _ 2 _ song1_verse1_rhythmn[b];
-if (song1_verse1_melody[b] > 0) {
-digitalWrite(led, HIGH);
-Serial.print(lyrics_verse1[c]);
-tone(piezo, song1_verse1_melody[b], notelength);
-c++;
-}
-b++;
-if (b >= sizeof(song1_verse1_melody) / sizeof(int)) {
-a++;
-b = 0;
-c = 0;
-}
-}
-else if (a == 4 || a == 6) { //chorus
-// chorus
-notelength = beatlength _ song1_chorus_rhythmn[b];
-if (song1_chorus_melody[b] > 0) {
-digitalWrite(led, HIGH);
-Serial.print(lyrics_chorus[c]);
-tone(piezo, song1_chorus_melody[b], notelength);
-c++;
-}
-b++;
-if (b >= sizeof(song1_chorus_melody) / sizeof(int)) {
-Serial.println("");
-a++;
-b = 0;
-c = 0;
-}
-}
-delay(notelength); // necessary because piezo is on independent timer
-noTone(piezo);
-digitalWrite(led, LOW);
-delay(notelength \* beatseparationconstant); // create separation between notes
-if (a == 7) { // loop back around to beginning of song
-a = 1;
-}
+  int notelength;
+  if (a == 1 || a == 2) { // Intro
+    // intro
+    notelength = beatlength * song1_intro_rhythmn[b];
+    if (song1_intro_melody[b] > 0) { // if not a rest, play note
+    digitalWrite(led, HIGH);
+    tone(piezo, song1_intro_melody[b], notelength);
+    }
+
+    b++;
+    if (b >= sizeof(song1_intro_melody) / sizeof(int)) {
+      a++;
+      b = 0;
+      c = 0;
+    }
+  } else if (a == 3 || a == 5) { // Verse 1
+    // verse
+    notelength = beatlength * 2 * song1_verse1_rhythmn[b];
+    if (song1_verse1_melody[b] > 0) {
+    digitalWrite(led, HIGH);
+    Serial.print(lyrics_verse1[c]);
+    tone(piezo, song1_verse1_melody[b], notelength);
+    c++;
+    }
+    b++;
+    if (b >= sizeof(song1_verse1_melody) / sizeof(int)) {
+    a++;
+    b = 0;
+    c = 0;
+    }
+  } else if (a == 4 || a == 6) { //chorus
+    // chorus
+    notelength = beatlength * song1_chorus_rhythmn[b];
+    if (song1_chorus_melody[b] > 0) {
+      digitalWrite(led, HIGH);
+      Serial.print(lyrics_chorus[c]);
+      tone(piezo, song1_chorus_melody[b], notelength);
+      c++;
+    }
+
+    b++;
+    if (b >= sizeof(song1_chorus_melody) / sizeof(int)) {
+      Serial.println("");
+      a++;
+      b = 0;
+      c = 0;
+    }
+  }
+
+  delay(notelength); // necessary because piezo is on independent timer
+  noTone(piezo);
+  digitalWrite(led, LOW);
+  delay(notelength * beatseparationconstant); // create separation between notes
+  if (a == 7) { // loop back around to beginning of song
+    a = 1;
+  }
 }
 ```