Struct YM2149 

pub struct YM2149<C>
where
    C: CommandOutput,
{
    pub channel_data: [AudioChannelData; 3],
    pub last_used_channel: Option<usize>,
    /* private fields */
}

A YM2149 chip struct.

The master_clock_frequency value is used to convert a frequency into a tone period by .tone_hz()

Example code:

use ym2149_core::{
    command::{Command, CommandOutput},
    io::IoPortMixerSettings,
    chip::YM2149
};

struct DebugWriter;

impl CommandOutput for DebugWriter {
    fn execute(&mut self, command: Command) {
        print!("Register 0b{:08b} ({:?}), ", command.register, command.register);
        println!("0b{:08b} ({:?})", command.value, command.value);
    }
}

let mut chip = YM2149::new(
    DebugWriter{},
    2_000_000,
).expect("Error building chip");

chip.setup_io_and_mixer(
    IoPortMixerSettings {
        tone_ch_a: true,
        ..Default::default()
    }
);

Fields

channel_data: [AudioChannelData; 3]

last_used_channel: Option<usize>

Implementations

impl<C> YM2149<C>

where C: CommandOutput,

pub fn new( command_output: C, master_clock_frequency: u32, ) -> Result<Self, Error>

Create a new struct for the YM2149.

pub fn command<R: ValidRegister + Copy>(&mut self, register: R, value: u8)

Send a Command.

pub fn setup_io_and_mixer(&mut self, settings: IoPortMixerSettings)

Setup the IO ports and the internal mixer according to the IoPortMixerSettings specified.

pub fn write_io(&mut self, port: IoPort, value: u8)

Write a value to one of the chip’s GPIO ports. Note: This is a simple helper function, equivalent to self.command(port as u8, value);

pub fn set_envelope_frequency( &mut self, frequency: EnvelopeFrequency, ) -> Result<u16, Error>

Set the envelope generator’s frequency.

pub fn set_envelope_shape(&mut self, envelope: &Envelope)

Set the envelope generator’s shape.

pub fn tone(&mut self, channel: AudioChannel, period: u16) -> Result<(), Error>

Play a tone with a TP of period on an AudioChannel.

The formula for the frequency is f = fMaster / (16 * TP), where: - f: target frequency - fMaster: master clock frequency - TP: tone period

pub fn tone_hz( &mut self, channel: AudioChannel, frequency: u32, ) -> Result<(), Error>

Play a tone of a given frequency in Hz on an AudioChannel.

pub fn play_note( &mut self, channel: AudioChannel, note: &Note, ) -> Result<(), Error>

Play a Note on an AudioChannel.

pub fn pitch_bend( &mut self, channel: AudioChannel, byte1: u8, byte2: u8, replay_last: bool, ) -> Result<f32, Error>

Set an AudioChannel’s pitch bend (takes a MIDI command).

pub fn replay_last_note(&mut self, channel: AudioChannel) -> Result<(), Error>

Replay the last played note on a given channel.

pub fn play_note_with_envelope( &mut self, channel: AudioChannel, note: &Note, with_envelope: &Envelope, ) -> Result<(), Error>

Play a Note on an AudioChannel with a given Envelope.

pub fn set_noise_freq(&mut self, frequency: u8) -> Result<(), Error>

Set the frequency of the noise generator.

Mask: 0x1F

pub fn level(&mut self, channel: AudioChannel, level: u8)

Set the volume of an AudioChannel.

Note: The channel level registers store 5 bits of data per channel.

---

From the datasheet:

• Mode M selects whether the level is fixed (when M = 0) or variable (M = 1).
• When M = 0, the level is determined from one of 16 by level selection signals L3, L2, L1, and L0 which compromise the lower four bits.
• When M = 1, the level is determined by the 5 bit output of E4, E3, E2, E1, and E0 of the envelope generator of the SSG.

B7 (MSB)	B6	B5	B4	B3	B2	B1	B0
N/A	N/A	N/A	M	L3	L2	L1	L0

Trait Implementations

impl<C> Debug for YM2149<C>

where C: CommandOutput + Debug,

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.