def test(driver):
with driver.open_unit() as device:
five_milliseconds = 0.005
config = TimebaseOptions(
max_time_interval=five_milliseconds,
no_of_samples=None,
min_collection_time=five_milliseconds * 30,
oversample=1)
timebase_info = device.find_timebase(config)
self.assertValidTimebases(config, timebase_info)
def test_invalid_config(self):
request = TimebaseOptions(max_time_interval=0.005,
no_of_samples=None,
min_collection_time=1.)
actual_timebase = 0.004
required_max_samples = int(
math.ceil(request.min_collection_time / actual_timebase))
response = TimebaseInfo(timebase_id=7,
time_interval=0.004,
time_units=None,
max_samples=required_max_samples - 5,
segment_id=0)
self.assertFalse(Device._validate_timebase(request, response))
def test(driver):
with driver.open_unit() as device:
threw = False
try:
# we ask for a config which requires 1TS (one terra-sample) of memory on device.
smallest_timebase = 1.e-8
one_terra_sample = 1.e12
duration = smallest_timebase * one_terra_sample
config = TimebaseOptions(
max_time_interval=smallest_timebase,
no_of_samples=one_terra_sample,
min_collection_time=duration)
timebase_info = device.find_timebase(config)
except NoValidTimebaseForOptionsError:
threw = True
if not threw:
return "didn't throw an NoValidTimebaseForOptionsError."
def test(driver):
with driver.open_unit() as device:
threw = False
try:
# we ask for a config which cannot be achieved (specifying all 3 variables can lead to invalid
# configs.)
no_of_samples = 150
duration = 0.4
computed_timebase = duration / no_of_samples
max_timebase_requested = computed_timebase / 4
config = TimebaseOptions(
max_time_interval=max_timebase_requested,
no_of_samples=no_of_samples,
min_collection_time=duration)
timebase_info = device.find_timebase(config)
except NoValidTimebaseForOptionsError:
threw = True
if not threw:
return "didn't throw an NoValidTimebaseForOptionsError."
def main():
parser = argparse.ArgumentParser()
parser.add_argument('-b', '--bits', type=float, default=8)
args = parser.parse_args()
if args.bits < 8:
raise ValueError("you need to specify bits to be at least 8.")
with find_unit() as device:
print("found PicoScope: %s" % (device.info, ))
channel_configs = [
ChannelConfig(name='A', enabled=True, coupling='DC', range_peak=5.)
]
actual_interval = 1.e-6
oversample = int(round(4**(args.bits - 8)))
print("using oversample of", oversample)
min_total_capture_time = 2.e-3
# using oversample, we can pump up the effective resolution of the scope (while reducing the total available
# sample memory).
timebase_options = TimebaseOptions(
max_time_interval=actual_interval,
no_of_samples=None,
min_collection_time=min_total_capture_time,
oversample=oversample)
times, voltages, overflow_warnings = device.capture_block(
timebase_options, channel_configs)
for channel, data in voltages.items():
label = "Channel %s" % channel
if channel in overflow_warnings:
label += " (over range)"
plt.plot(times, data, label=label)
plt.xlabel('Time / s')
plt.ylabel('Amplitude / V')
plt.legend()
plt.show()
#
# Copyright (C) 2018 Pico Technology Ltd. See LICENSE file for terms.
#
from __future__ import print_function
from picosdk.discover import find_unit
from picosdk.device import ChannelConfig, TimebaseOptions
import matplotlib.pyplot as plt
with find_unit() as device:
print("found PicoScope: %s" % (device.info, ))
channel_configs = [ChannelConfig('A', True, 'DC', 5.)]
microsecond = 1.e-6
# the entry-level scopes only have about 8k-samples of memory onboard for block mode, so only ask for 6k samples.
timebase_options = TimebaseOptions(microsecond, None, 6000 * microsecond)
times, voltages, overflow_warnings = device.capture_block(
timebase_options, channel_configs)
for channel, data in voltages.items():
label = "Channel %s" % channel
if channel in overflow_warnings:
label += " (over range)"
plt.plot(times, data, label=label)
plt.xlabel('Time / s')
plt.ylabel('Amplitude / V')
plt.legend()
plt.show()
