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pll: merge advance into update (like rpll)

master
Robert Jördens 2021-06-03 16:03:54 +00:00
parent 971bc1109d
commit 10da2d38ae
1 changed files with 21 additions and 23 deletions
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44
dsp/src/pll.rs
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@ -45,7 +45,7 @@ impl PLL {
/// The signal's phase/frequency is reconstructed relative to the sampling period.
///
/// Args:
/// * `x`: New input phase sample.
/// * `x`: New input phase sample or None if a sample has been missed.
/// * `shift_frequency`: Frequency error scaling. The frequency gain per update is
/// `1/(1 << shift_frequency)`.
/// * `shift_phase`: Phase error scaling. The phase gain is `1/(1 << shift_phase)`
@ -55,36 +55,34 @@ impl PLL {
/// A tuple of instantaneous phase and frequency (the current phase increment).
pub fn update(
&mut self,
x: i32,
x: Option<i32>,
shift_frequency: u8,
shift_phase: u8,
) -> (i32, i32) {
debug_assert!((1..=30).contains(&shift_frequency));
debug_assert!((1..=30).contains(&shift_phase));
let e = x.wrapping_sub(self.f);
self.f = self.f.wrapping_add(
(1i32 << (shift_frequency - 1))
.wrapping_add(e)
.wrapping_sub(self.x)
>> shift_frequency,
);
self.x = x;
let f = self.f.wrapping_add(
(1i32 << (shift_phase - 1))
.wrapping_add(e)
.wrapping_sub(self.y)
>> shift_phase,
);
let f = if let Some(x) = x {
let e = x.wrapping_sub(self.f);
self.f = self.f.wrapping_add(
(1i32 << (shift_frequency - 1))
.wrapping_add(e)
.wrapping_sub(self.x)
>> shift_frequency,
);
self.x = x;
self.f.wrapping_add(
(1i32 << (shift_phase - 1))
.wrapping_add(e)
.wrapping_sub(self.y)
>> shift_phase,
)
} else {
self.x = self.x.wrapping_add(self.f);
self.f
};
self.y = self.y.wrapping_add(f);
(self.y, f)
}
/// Advance the PLL without providing a new timestamp.
pub fn advance(&mut self) -> (i32, i32) {
self.x = self.x.wrapping_add(self.f);
self.y = self.y.wrapping_add(self.f);
(self.y, self.f)
}
}
#[cfg(test)]