35 lines
722 B
Rust
35 lines
722 B
Rust
#![no_std]
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#![no_main]
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use defmt::*;
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use embassy_stm32::dac::{DacCh1, Value};
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use {defmt_rtt as _, panic_probe as _};
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#[cortex_m_rt::entry]
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fn main() -> ! {
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let p = embassy_stm32::init(Default::default());
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info!("Hello World!");
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let mut dac = DacCh1::new_blocking(p.DAC1, p.PA4);
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loop {
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for v in 0..=255 {
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dac.set(Value::Bit8(to_sine_wave(v)));
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}
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}
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}
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use micromath::F32Ext;
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fn to_sine_wave(v: u8) -> u8 {
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if v >= 128 {
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// top half
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let r = 3.14 * ((v - 128) as f32 / 128.0);
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(r.sin() * 128.0 + 127.0) as u8
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} else {
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// bottom half
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let r = 3.14 + 3.14 * (v as f32 / 128.0);
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(r.sin() * 128.0 + 127.0) as u8
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}
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}
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