create stub AMPS handset emulator

amps-handset-emu/src/audio.rs

@@ -0,0 +1,20 @@
+use cpal::{StreamConfig, traits::{DeviceTrait, HostTrait}};
+
+pub fn play_audio(signal: &[f32]) -> Result<(), Box<dyn std::error::Error>> {
+    let host = cpal::default_host();
+    let device = host.default_output_device()?.config();
+    let config = device.default_output_config()?.config();
+
+    let stream = device.build_output_stream(
+        &config,
+        move |data: &mut [f32], _: &cpal::OutputCallbackInfo| {
+            data.copy_from_slice(&signal[..data.len()]);
+        },
+        |err| eprintln!("Error: {:?}", err),
+        None
+    )?;
+
+    stream.play()?;
+    std::thread::sleep(std::time::Duration::from_secs(5));
+    Ok(())
+}