chore: Add course material

397/Ex21/Main.cpp

@@ -0,0 +1,31 @@
+
+
+#include "Keyboard.h"
+#include "Pelican.h"
+#include "TimerSet.h"
+
+#include <cctype> // provides toupper()
+
+static TimerSet theTimerSet;
+
+int main() {
+    Keyboard kbd;
+    Pelican thePelican(30, 0);
+
+    char c = 0;
+
+    while (std::toupper(c) != 'Q') { // loop until 'Q' is pressed
+
+        while (!kbd.isCharAvail()) {
+            theTimerSet.pollAllTimers(); // no key press to process, poll the timers
+        }
+
+        c = kbd.getChar(); // get the character
+        if (c == ' ') {
+            // it's a space, so press the WAIT button
+            thePelican.press();
+        }
+    }
+
+    return 0;
+}