create stub AMPS handset emulator

amps-handset-emu/src/main.rs

@@ -0,0 +1,33 @@
+use fsk::fsk_modulate;
+use text_io::scan;
+use std::io;
+
+mod fsk;
+mod audio;
+
+fn main() -> Result<(), io::Error> {
+    println!("Press 1 to send test tone");
+    println!("Press 0 to exit");
+
+    let a: i32;
+    scan!("{}", a);
+
+    match a {
+        1 => {
+            println!("1 has been pressed! No test tone implemented yet");
+            let tone: signal;
+            tone = fsk_modulate([0x25, 0x08, 0x00, 0x25, 0xA0]);
+            play_audio(tone);
+            return main();
+        },
+        0 => {
+            return Ok(());
+        }
+        _ => {
+            eprintln!("Invalid command.");
+            return Ok(());
+        }
+    }
+
+    //Ok(())
+}