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WRPLL: replace PI controller with new filter

This commit is contained in:
morgan 2024-05-08 16:19:11 +08:00 committed by sb10q
parent 285b02c4b1
commit cdf4ff24c0
1 changed files with 48 additions and 18 deletions

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@ -335,14 +335,34 @@ pub mod wrpll {
const COUNTER_WIDTH: u32 = 24;
const DIV_WIDTH: u32 = 2;
const KP: i32 = 6;
const KI: i32 = 2;
// y[n] = b0*x[n] + b1*x[n-1] + b2*x[n-2] - a1*y[n-1] - a2*y[n-2]
struct FilterParameters {
pub b0: f64,
pub b1: f64,
pub b2: f64,
pub a1: f64,
pub a2: f64,
}
const LPF: FilterParameters = FilterParameters {
b0: 0.07209205036273991,
b1: 0.14418410072547982,
b2: 0.07209205036273991,
a1: -0.6114078511562919,
a2: -0.10022394739274834,
};
static mut H_ADPLL1: i32 = 0;
static mut H_ADPLL2: i32 = 0;
static mut PERIOD_ERR1: i32 = 0;
static mut PERIOD_ERR2: i32 = 0;
static mut M_ADPLL1: i32 = 0;
static mut M_ADPLL2: i32 = 0;
static mut PHASE_ERR1: i32 = 0;
static mut PHASE_ERR2: i32 = 0;
static mut BASE_ADPLL: i32 = 0;
static mut H_LAST_ADPLL: i32 = 0;
static mut LAST_PERIOD_ERR: i32 = 0;
static mut M_LAST_ADPLL: i32 = 0;
static mut LAST_PHASE_ERR: i32 = 0;
#[derive(Clone, Copy)]
pub enum ISR {
@ -470,10 +490,14 @@ pub mod wrpll {
fn reset_plls(timer: &mut GlobalTimer) -> Result<(), &'static str> {
unsafe {
H_LAST_ADPLL = 0;
LAST_PERIOD_ERR = 0;
M_LAST_ADPLL = 0;
LAST_PHASE_ERR = 0;
H_ADPLL1 = 0;
H_ADPLL2 = 0;
PERIOD_ERR1 = 0;
PERIOD_ERR2 = 0;
M_ADPLL1 = 0;
M_ADPLL2 = 0;
PHASE_ERR1 = 0;
PHASE_ERR2 = 0;
}
set_adpll(i2c::DCXO::Main, 0)?;
set_adpll(i2c::DCXO::Helper, 0)?;
@ -517,11 +541,14 @@ pub mod wrpll {
fn helper_pll() -> Result<(), &'static str> {
let period_err = tag_collector::get_period_error();
unsafe {
// Based on https://hackmd.io/IACbwcOTSt6Adj3_F9bKuw?view#Integral-wind-up-and-output-limiting
let adpll = H_LAST_ADPLL + (KP + KI) * period_err - KP * LAST_PERIOD_ERR;
let adpll = ((LPF.b0 * period_err as f64) + (LPF.b1 * PERIOD_ERR1 as f64) + (LPF.b2 * PERIOD_ERR2 as f64)
- (LPF.a1 * H_ADPLL1 as f64)
- (LPF.a2 * H_ADPLL2 as f64)) as i32;
set_adpll(i2c::DCXO::Helper, BASE_ADPLL + adpll)?;
H_LAST_ADPLL = adpll;
LAST_PERIOD_ERR = period_err;
H_ADPLL2 = H_ADPLL1;
PERIOD_ERR2 = PERIOD_ERR1;
H_ADPLL1 = adpll;
PERIOD_ERR1 = period_err;
};
Ok(())
}
@ -529,11 +556,14 @@ pub mod wrpll {
fn main_pll() -> Result<(), &'static str> {
let phase_err = tag_collector::get_phase_error();
unsafe {
// Based on https://hackmd.io/IACbwcOTSt6Adj3_F9bKuw?view#Integral-wind-up-and-output-limiting
let adpll = M_LAST_ADPLL + (KP + KI) * phase_err - KP * LAST_PHASE_ERR;
let adpll = ((LPF.b0 * phase_err as f64) + (LPF.b1 * PHASE_ERR1 as f64) + (LPF.b2 * PHASE_ERR2 as f64)
- (LPF.a1 * M_ADPLL1 as f64)
- (LPF.a2 * M_ADPLL2 as f64)) as i32;
set_adpll(i2c::DCXO::Main, BASE_ADPLL + adpll)?;
M_LAST_ADPLL = adpll;
LAST_PHASE_ERR = phase_err;
M_ADPLL2 = M_ADPLL1;
PHASE_ERR2 = PHASE_ERR1;
M_ADPLL1 = adpll;
PHASE_ERR1 = phase_err;
};
Ok(())
}