Detailed Description

Ring Tone Text Transfer Language (RTTTL) interpreter.

RTTTL is a compact plaintext format for monophonic music, originally used for Nokia mobile-phone ringtones, e.g.:

Beethoven:d=4,o=5,b=160:c,e,c,g,c,c6,8b,8a,8g,8a,8g,8f,8e,8f,8e,8d,c,e,g,e,c6,g.

This class accepts RTTTL input and emits "notes" as duration and rate pairs, encoded as consecutive u16 + u32 values. Duration is measured in milliseconds. Rate zero indicates silence; otherwise it sets phase-increment per clock cycle as used in "cfgbus_piezo.vhd", i.e., rate = round(2^32 * freq_hz / refclk_hz).

Definition at line 33 of file codec_rtttl.h.

#include <codec_rtttl.h>

Inheritance diagram for satcat5::io::RtttlDecoder:

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Collaboration diagram for satcat5::io::RtttlDecoder:

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Public Member Functions
constexpr	RtttlDecoder (satcat5::io::Writeable *spkr, u64 refclk_hz)
	Link this decoder to a playback device. More...

void	flush ()
	If playback is in progress, halt immediately.

bool	play (const char *src)
	Decode and play the specified song (string input). More...

bool	play (satcat5::io::Readable *src)
	Decode and play the specified song (stream input). More...

virtual void	data_unlink (satcat5::io::Readable *src)
	Unlink this EventListener from the designated source, because the designated Readable object is being destroyed. More...

Protected Member Functions
void	data_rcvd (satcat5::io::Readable *src) override
	The data_rcvd() callback is polled whenever data is available. More...

bool	read_note (satcat5::io::Readable *src)

Protected Attributes
satcat5::io::Writeable *const	m_spkr
	Output device.

const u64	m_scale
	Frequency conversion.

u32	m_duration
	Default note duration.

u32	m_octave
	Default octave.

u32	m_whole_note
	Duration of whole note.

satcat5::io::PacketBuffer	m_queue
	Playback queue.

u8	m_raw [SATCAT5_RTTTL_BUFFER]
	Raw working buffer.

Constructor & Destructor Documentation

◆ RtttlDecoder()

constexpr satcat5::io::RtttlDecoder::RtttlDecoder	(	satcat5::io::Writeable *	spkr,
		u64	refclk_hz
	)

inlineconstexpr

Link this decoder to a playback device.

Parameters

spkr	Is the buffer for the playback device.
refclk_hz	Is the reference clock frequency, in Hz.

Definition at line 38 of file codec_rtttl.h.

Member Function Documentation

◆ data_rcvd()

void RtttlDecoder::data_rcvd ( satcat5::io::Readable * src )

overrideprotectedvirtual

The data_rcvd() callback is polled whenever data is available.

A pointer is provided to assist handlers with multiple sources. Child objects of io::EventListener MUST override this method.

Implements satcat5::io::EventListener.

Definition at line 111 of file codec_rtttl.cc.

◆ data_unlink()

virtual void satcat5::io::EventListener::data_unlink ( satcat5::io::Readable * src )

inlinevirtualinherited

Unlink this EventListener from the designated source, because the designated Readable object is being destroyed.

Child objects of io::EventListener MAY override this method if action is required.

Reimplemented in satcat5::io::Override, satcat5::io::MuxUp, satcat5::io::MuxDown, satcat5::io::BufferedPackets, satcat5::io::BufferedStream, satcat5::io::BufferedCopy, satcat5::eth::SwitchLogReader, satcat5::eth::Dispatch, satcat5::ccsds_spp::Dispatch, satcat5::ccsds_aos::Dispatch, satcat5::ccsds_aos::Channel, satcat5::test::MockOffload::Port, and satcat5::freertos::MessageCopy.

Definition at line 54 of file io_readable.h.

◆ play() [1/2]

bool RtttlDecoder::play ( const char * src )

Decode and play the specified song (string input).

Returns: True if the entire sequence was enqueued for playback.

Definition at line 48 of file codec_rtttl.cc.

◆ play() [2/2]

bool RtttlDecoder::play ( satcat5::io::Readable * src )

Decode and play the specified song (stream input).

Returns: True if the entire sequence was enqueued for playback.

Definition at line 58 of file codec_rtttl.cc.

The documentation for this class was generated from the following files: