Phil Schatzmann pschatzmann

USB Audio Testing Plan

Platform × Direction (core tests)

#	Platform	Mode	Key settings	Test
1	ESP32	TX	defaults (`enable_multi_sample_rate=false`)	Record 5s with `arecord`, play back, verify clean sine
2	ESP32	RX	defaults	Play `test.wav` with `aplay`, verify `rxXfer > 0`, MeasuringStream output
3	ESP32	RXTX	`enable_ep_in=true, enable_ep_out=true`	Record AND play simultaneously
4	RP2040	TX	defaults	Record with `arecord`, verify clean sine

Yesterday I was ask to extend my Arduino AudioTools library to support RTTTL. To be honest, I had no clue what this is, so I had to look it up: RTTTL stands for Ring Tone Text Transfer Language and was developed by Nokia to transfer ringtones to cellphones.

It basically descibes the notes and durations in simple text form. My library supports different sound generators and also provides the frequencies of all notes: so all I needed was to provide a parser for RTTTL and link it up with the existing functionality.

The new class is called RTTTOutput and you just provide the generator and output device in the constructor and then you can play the audio by printing the RTTTS string


	/**
	* A Simple exension of the WiFiUDP class which makes sure that the basic Stream
	* functioinaltiy which is used as AudioSource and AudioSink
	* @ingroup communications
	* @author Phil Schatzmann
	* @copyright GPLv3
	*/

	class UDPStream : public Stream {

	#!/usr/bin/env python

	import argparse
	import re
	import os
	import subprocess
	import sys
	from termcolor import colored

	# update the following default values to what is relevant for your system