noptica-rs/src/wavemeter.rs

111 lines
4.1 KiB
Rust

extern crate argparse;
extern crate num_traits;
extern crate serde_derive;
extern crate serde_json;
use argparse::{ArgumentParser, StoreTrue, Store};
use serde_derive::Deserialize;
use std::error::Error;
use std::fs::File;
use std::io::BufReader;
use std::path::Path;
mod noptica;
#[derive(Deserialize, Debug)]
struct Config {
sample_command: String, // Shell command to start the logic analyzer.
sample_rate: f64, // Sample rate of the logic analyzer in Hz.
// The logic analyzer command must produce a stream of 4-bit nibbles on its
// standard output, which are continuously sampled at the nominal sample rate.
// Each of the signals below are mapped to one bit within each nibble.
bit_ref: u8, // Bit# for REF signal of the reference laser head (HP 5501B).
bit_meas: u8, // Bit# for displacement measurement detector (HP 10780).
bit_input: u8, // Bit# for input laser interference detector.
// The REF DPLL locks to the REF output of the reference laser and provides REF phase
// information at each sample of the logic analyzer.
// ref_min and ref_max are used to initialize the DPLL and clamp its NCO frequency.
ref_min: f64, // Minimum REF frequency in Hz.
ref_max: f64, // Maximum REF frequency in Hz.
refpll_ki: i64, // Integration constant of the DPLL loop filter.
refpll_kp: i64, // Proportionality constant of the DPLL loop filter.
ref_wavelength: f64, // Wavelength of the reference laser in m.
scan_displacement: f64, // Optical path difference across one scan cycle in m (use -c).
scan_frequency: f64, // Frequency of the scan in Hz.
scan_blanking: f64, // Fraction of the scan period that is blanked at the beginning
// and end of each slope (4 times per scan period).
}
fn read_config_from_file<P: AsRef<Path>>(path: P) -> Result<Config, Box<dyn Error>> {
let file = File::open(path)?;
let reader = BufReader::new(file);
let u = serde_json::from_reader(reader)?;
Ok(u)
}
fn do_calibrate(config: &Config) {
let mut sample_count = 0;
let max_sample_count = (config.sample_rate/4.0) as u32;
let mut position_min = i64::max_value();
let mut position_max = i64::min_value();
let mut refpll = noptica::Dpll::new(
noptica::Dpll::frequency_to_ftw(config.ref_min, config.sample_rate),
noptica::Dpll::frequency_to_ftw(config.ref_max, config.sample_rate),
config.refpll_ki,
config.refpll_kp);
let mut position_tracker = noptica::PositionTracker::new();
noptica::sample(&config.sample_command, |rising, _falling| {
refpll.tick(rising & (1 << config.bit_ref) != 0);
if rising & (1 << config.bit_meas) != 0 {
let position = position_tracker.edge(refpll.get_phase_unwrapped());
if position > position_max {
position_max = position;
}
if position < position_min {
position_min = position;
}
}
sample_count += 1;
if sample_count == max_sample_count {
let displacement = ((position_max-position_min) as f64)/(noptica::Dpll::TURN as f64)*config.ref_wavelength;
println!("{} um", 1.0e6*displacement);
sample_count = 0;
position_min = i64::max_value();
position_max = i64::min_value();
}
})
}
fn do_wavemeter(config: &Config) {
println!("TODO {}", config.sample_command);
}
fn main() {
let mut calibrate = false;
let mut config_file = "wavemeter.json".to_string();
{
let mut ap = ArgumentParser::new();
ap.refer(&mut calibrate)
.add_option(&["-c", "--calibrate"], StoreTrue,
"Calibrate scan displacement");
ap.refer(&mut config_file)
.add_option(&["--config"], Store,
"Configuration file");
ap.parse_args_or_exit();
}
let config = read_config_from_file(config_file).unwrap();
if calibrate {
do_calibrate(&config);
} else {
do_wavemeter(&config);
}
}