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author | jaseg <git@jaseg.net> | 2018-05-20 15:54:03 +0200 |
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committer | jaseg <git@jaseg.net> | 2018-05-20 15:54:03 +0200 |
commit | cba83e780a9350eb45eb1c2f09fc87f5d389e1ac (patch) | |
tree | 89232388812444e2f95242e2b49d68d0de510f1c /doc/measure_spectrum.py | |
parent | f4d511afdb126de676914a74bf5143d913f62a4f (diff) | |
download | olsndot-cba83e780a9350eb45eb1c2f09fc87f5d389e1ac.tar.gz olsndot-cba83e780a9350eb45eb1c2f09fc87f5d389e1ac.tar.bz2 olsndot-cba83e780a9350eb45eb1c2f09fc87f5d389e1ac.zip |
Move documentation and simulation stuff to its own subdir
Diffstat (limited to 'doc/measure_spectrum.py')
-rw-r--r-- | doc/measure_spectrum.py | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/doc/measure_spectrum.py b/doc/measure_spectrum.py new file mode 100644 index 0000000..70f4e9b --- /dev/null +++ b/doc/measure_spectrum.py @@ -0,0 +1,122 @@ +#!/usr/bin/env python3 + +import time +import statistics +import sqlite3 +from datetime import datetime + +from pyBusPirateLite import BitBang + +if __name__ == '__main__': + import argparse + + parser = argparse.ArgumentParser() + parser.add_argument('-s', '--steps', type=int, nargs='?', default=400, help='Steps to run through') + parser.add_argument('-k', '--skip', type=int, nargs='?', default=2, help='Steps skip between measurements for shorter runtime') + parser.add_argument('-d', '--database', default='spectra.sqlite3', help='sqlite3 database file to store results in') + parser.add_argument('-w', '--wait', type=float, default=2.0, help='time to wait between samples in seconds') + parser.add_argument('-o', '--oversample', type=int, default=32, help='oversampling ratio') + parser.add_argument('-g', '--gain', type=float, default=None, help='Transimpedance gain of amplifier in MOhm') + parser.add_argument('-c', '--comment', help='run comment') + parser.add_argument('-p', '--port', default='/dev/serial/by-id/usb-FTDI_FT232R_USB_UART_AD01W1RF-if00-port0', help='Serial port device of the control buspirate') + parser.add_argument('run_name', nargs='?', default='auto') + parser.add_argument('color', help='Captured color channel') + args = parser.parse_args() + + db = sqlite3.connect(args.database) + db.execute(""" + CREATE TABLE IF NOT EXISTS runs ( + capture_id INTEGER PRIMARY KEY, + name TEXT, + comment TEXT, + color TEXT, -- Captured color channel + gain REAL, -- Preamplifier transimpedance in Ohms + timestamp REAL -- unix timestamp in fractional seconds + )""") + db.execute(""" + CREATE TABLE IF NOT EXISTS measurements ( + measurement_id INTEGER PRIMARY KEY, + capture_id INTEGER, + led_on INTEGER, + step INTEGER, + voltage REAL, -- volts + voltage_stdev REAL, -- volts + timestamp REAL, -- unix timestamp in fractional seconds + FOREIGN KEY (capture_id) REFERENCES runs)""") + + class BPState: + def __init__(self, port): + self.bp = BitBang(port) + self._led = 0 + self._stepper_dir = 'down' + self.reinit() + + def reinit(self): + self.bp.enter_bb() + self.led(self._led) + self.stepper_direction(self._stepper_dir) + self.bp.cs = 0 + + def led(self, st): + self._led = st + self.bp.mosi = st + + def stepper_direction(self, direction): + self._stepper_dir = direction + self.bp.aux = 0 if direction == 'down' else 1 + + def step(self): + self.bp.cs = 1 + time.sleep(0.005) + self.bp.cs = 0 + time.sleep(0.005) + + def adc(self, oversampling): + self.reinit() + return [ self.bp.adc_value for _ in range(oversampling) ] + + bp = BPState(args.port) + + with db: + cur = db.cursor() + cur.execute('INSERT INTO runs(name, comment, color, gain, timestamp) VALUES (?, ?, ?, ?, ?)', + (args.run_name, args.comment, args.color, args.gain*1e6, time.time())) + capture_id = cur.lastrowid + + print('Starting capture {} "{}" at {:%y-%m-%d %H:%M:%S:%f}'.format(capture_id, args.run_name, datetime.now())) + print('[measurement id] " " [step number] " " [reading (V)]') + + bp.stepper_direction('down') + for _ in range(10): + bp.step() + + bp.stepper_direction('up') + for step in range(0, args.steps+args.skip, args.skip): # Run one skip past end to capture both interval boundaries + for led_val in [1]: # This can be used for self-calibration. + try: + bp.led(led_val) + time.sleep(args.wait) + + readings = bp.adc(args.oversample) + mean, stdev = statistics.mean(readings), statistics.stdev(readings) + + with db: + cur = db.cursor() + cur.execute(''' + INSERT INTO measurements ( + capture_id, led_on, step, voltage, voltage_stdev, timestamp + ) VALUES (?, ?, ?, ?, ?, ?)''', + (capture_id, led_val, step, mean, stdev, time.time())) + print('{:08d} {:03} {}: {:5.4f} stdev {:5.4f}'.format( + cur.lastrowid, step, led_val, mean, stdev)) + except KeyboardInterrupt: + raise + except TypeError as e: + print('Buspirate hiccup, ignoring:', e) + for _ in range(args.skip): + bp.step() + + bp.stepper_direction('down') + for _ in range(args.steps+args.skip): + bp.step() + |