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neil.hamilton
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Add ps4000aExamples/ps4000aRapidBlockWaveformAveragingExample.py showing how to average together multiple buffers from a single rapid block capture
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‎picosdk/PicoConnectProbes.py‎

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#
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# Copyright (C) 2024 Pico Technology Ltd. See LICENSE file for terms.
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#
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"""
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This is a Python module defining the enumerations from the PicoConnectProbes.h C header
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file for use with various PicoScope oscilloscopes driver API functions.
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"""
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from ctypes import *
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from picosdk.constants import make_enum
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from picosdk.library import Library
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class PicoConnectProbeslib(Library):
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def __init__(self):
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super(PicoConnectProbeslib, self).__init__("picoConnectProbes")
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picoConnectProbes = PicoConnectProbeslib()
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def _define_pico_probe_range_info():
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PICO_PROBE_NONE_NV = 0
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PICO_X1_PROBE_NV = 1
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PICO_X10_PROBE_NV = 10
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return {k.upper(): v for k, v in locals().items() if k.startswith("PICO")}
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picoConnectProbes.PICO_PROBE_RANGE_INFO = _define_pico_probe_range_info

‎picosdk/functionsExhibitions.py‎

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#
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# Copyright (C) 2018 Pico Technology Ltd. See LICENSE file for terms.
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#
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import numpy as np
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import openpyxl
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from math import floor, log2, log10
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def dataImporter(name):
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workbook = openpyxl.load_workbook(name, data_only = True)
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sheet = workbook['filterParameters']
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noOfChannels = sheet.cell(row = 2, column = 1).value
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bits = sheet.cell(row = 2, column = 2).value
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samplingRate = sheet.cell(row = 2, column = 3).value
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sampleLength = sheet.cell(row = 2, column = 4).value
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return noOfChannels, bits, samplingRate, sampleLength
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def ps6000aTimebase(samplingRate):
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sampleInterval = (1/samplingRate)/1000000 #s
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breakPoint = 6.4/1000000000
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if sampleInterval >= breakPoint:
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timebase = floor((sampleInterval * 156250000)+5)
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else:
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timebase = floor(log2(sampleInterval * 5000000000))
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return timebase
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def ps5000aTimebase(samplingRate):
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sampleInterval = (1/samplingRate)/1000000 #s
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breakPoint = 8/1000000000
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if sampleInterval >= breakPoint:
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timebase = floor((sampleInterval * 125000000)+2)
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else:
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timebase = floor(log2(sampleInterval * 1000000000))
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return timebase
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def ps3000aTimebase(samplingRate):
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sampleInterval = (1/samplingRate)/1000000 #s
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breakPoint = 8/1000000000
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if sampleInterval >= breakPoint:
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timebase = floor((sampleInterval * 125000000)+2)
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else:
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timebase = floor(log2(sampleInterval * 1000000000))
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return timebase
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def ps4000aTimebase(samplingRate):
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timebase = floor((80/samplingRate)-1)
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return timebase
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def ps2000aTimebase(samplingRate):
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sampleInterval = (1/samplingRate)/1000000 #s
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breakPoint = 4/1000000000
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if sampleInterval>= breakPoint:
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timebase = floor((sampleInterval*125000000)+2)
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else:
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timebase = floor(log2(sampleInterval * 1000000000))
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return timebase
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def ps2000Timebase(sampleRate):
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#assumes sample rate is in Hz
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#assumes sample interval in s
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sampleInterval = (1/sampleRate)
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timebase = floor(log10(sampleInterval*1000000000))
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return timebase
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def BitEnumSelector(bits):
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if bits <= 8:
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enum = 0
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elif bits <= 10:
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enum = 10
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else:
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enum = 1
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return enum
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def saveConfigFile(channels, bits, sampleRate,captureLength, maxAmplitude, segments):
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configValues = [channels, bits, sampleRate, captureLength, maxAmplitude, segments]
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# Save the list to a text file
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with open('configValues.txt', 'w') as file:
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# Write each element of the list on a new line
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for value in configValues:
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file.write(f"{value}\n")
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return
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def loadConfigValues():
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restored_configValues = []
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with open('configValues.txt', 'r') as file:
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for line in file:
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value = line.strip()
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# Convert to integer or float as necessary
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if '.' in value:
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restored_configValues.append(float(value))
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else:
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restored_configValues.append(int(value))
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channels = restored_configValues[0]
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bits = restored_configValues[1]
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sampleRate = restored_configValues[2]
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captureLength = restored_configValues[3]
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maxAmplitude = restored_configValues[4]
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segments = restored_configValues[5]
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return channels, bits, sampleRate, captureLength, maxAmplitude, segments

‎picosdk/ps2000.py‎

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from picosdk.library import Library
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from picosdk.errors import ArgumentOutOfRangeError
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from picosdk.constants import make_enum
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from picosdk.ctypes_wrapper import C_CALLBACK_FUNCTION_FACTORY
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class Ps2000lib(Library):
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ps2000.MAX_MEMORY = 32e3
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ps2000.PS2000_TIME_UNITS = make_enum([
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'PS2000_FS',
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'PS2000_PS',
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'PS2000_NS',
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'PS2000_US',
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'PS2000_MS',
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'PS2000_S',
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'PS2000_MAX_TIME_UNITS',
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])
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doc = """ int16_t ps2000_open_unit
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(
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void
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ps2000.PICO_INFO = {k: v for k, v in ps2000.PICO_INFO.items() if v <= 0x00000005}
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ps2000.PICO_INFO["PICO_ERROR_CODE"] = 0x00000006
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ps2000.PICO_INFO["PICO_KERNEL_DRIVER_VERSION"] = 0x00000007
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doc = """ void *my_get_overview_buffers
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(
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int16_t **overviewBuffers
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int16_t overflow,
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uint32_t triggerAt,
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int16_t triggered,
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int16_t autoStop,
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uint32_t nValues
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);
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define a python function which accepts the correct arguments, and pass it to the constructor of this type.
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"""
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ps2000.GetOverviewBuffersType = C_CALLBACK_FUNCTION_FACTORY(None,
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c_void_p,
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c_int16,
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c_uint32,
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c_int16,
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c_int16,
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c_uint32)
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ps2000.GetOverviewBuffersType.__doc__ = doc

‎picosdk/psospaBlockExample.py‎

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#
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# Copyright (C) 2024 Pico Technology Ltd. See LICENSE file for terms.
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#
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# PSOSPA BLOCK MODE EXAMPLE
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# This example opens a psospa driver device, sets up two channels and a trigger then collects a block of data.
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# This data is then plotted as mV against time in ns.
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import ctypes
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import numpy as np
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from picosdk.psospa import psospa as ps
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from picosdk.PicoDeviceEnums import picoEnum as enums
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from picosdk.PicoDeviceStructs import picoStruct as structs
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# from picosdk.PicoConnectProbes import picoConnectProbes as probes
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import matplotlib.pyplot as plt
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from picosdk.functions import adc2mVV2, mV2adcV2, assert_pico_ok
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# Create chandle and status ready for use
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chandle = ctypes.c_int16()
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status = {}
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# Open a psospa driver device
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# returns handle for future API functions
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resolution = enums.PICO_DEVICE_RESOLUTION["PICO_DR_8BIT"]
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status["openUnit"] = ps.psospaOpenUnit(ctypes.byref(chandle), None, resolution, None)
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assert_pico_ok(status["openUnit"])
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# Set channel A on
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# handle = chandle
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channelA = enums.PICO_CHANNEL["PICO_CHANNEL_A"]
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coupling = enums.PICO_COUPLING["PICO_DC"]
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rangeMax = 2000000000 #nV
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rangeMin = -rangeMax #nV
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rangeType = 0 #probes.PICO_PROBE_RANGE_INFO["PICO_PROBE_NONE_NV"]
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analogueOffset = 0
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bandwidth = enums.PICO_BANDWIDTH_LIMITER["PICO_BW_FULL"]
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status["setChannelA"] = ps.psospaSetChannelOn(chandle, channelA, coupling, rangeMin, rangeMax, rangeType, analogueOffset, bandwidth)
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assert_pico_ok(status["setChannelA"])
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# set channel B-D off
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for x in range (1, 3, 1):
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channel = x
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status["setChannel",x] = ps.psospaSetChannelOff(chandle,channel)
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assert_pico_ok(status["setChannel",x])
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# get max ADC value
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# handle = chandle
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minADC = ctypes.c_int16()
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maxADC = ctypes.c_int16()
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status["getAdcLimits"] = ps.psospaGetAdcLimits(chandle, resolution, ctypes.byref(minADC), ctypes.byref(maxADC))
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assert_pico_ok(status["getAdcLimits"])
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# Set simple trigger on channel A, 1 V rising with 1 s autotrigger
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# handle = chandle
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# enable = 1
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source = channelA
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# threshold = 100 mV
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direction = enums.PICO_THRESHOLD_DIRECTION["PICO_RISING"]
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# delay = 0 s
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# autoTriggerMicroSeconds = 1000000 us
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status["setSimpleTrigger"] = ps.psospaSetSimpleTrigger(chandle, 1, source, mV2adcV2(100,rangeMax,maxADC), direction, 0, 1000000)
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assert_pico_ok(status["setSimpleTrigger"])
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# Get fastest available timebase
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# handle = chandle
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enabledChannelFlags = enums.PICO_CHANNEL_FLAGS["PICO_CHANNEL_A_FLAGS"]
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timebase = ctypes.c_uint32(0)
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timeInterval = ctypes.c_double(0)
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# resolution = resolution
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status["getMinimumTimebaseStateless"] = ps.psospaGetMinimumTimebaseStateless(chandle, enabledChannelFlags, ctypes.byref(timebase), ctypes.byref(timeInterval), resolution)
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print("timebase = ", timebase.value)
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print("sample interval =", timeInterval.value, "s")
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# Set number of samples to be collected
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noOfPreTriggerSamples = 500000
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noOfPostTriggerSamples = 1000000
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nSamples = noOfPostTriggerSamples + noOfPreTriggerSamples
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# Create buffers
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bufferAMax = (ctypes.c_int16 * nSamples)()
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bufferAMin = (ctypes.c_int16 * nSamples)() # used for downsampling which isn't in the scope of this example
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# Set data buffers
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# handle = chandle
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# channel = channelA
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# bufferMax = bufferAMax
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# bufferMin = bufferAMin
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# nSamples = nSamples
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dataType = enums.PICO_DATA_TYPE["PICO_INT16_T"]
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waveform = 0
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downSampleMode = enums.PICO_RATIO_MODE["PICO_RATIO_MODE_RAW"]
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clear = enums.PICO_ACTION["PICO_CLEAR_ALL"]
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add = enums.PICO_ACTION["PICO_ADD"]
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action = clear|add # PICO_ACTION["PICO_CLEAR_WAVEFORM_CLEAR_ALL"] | PICO_ACTION["PICO_ADD"]
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status["setDataBuffers"] = ps.psospaSetDataBuffers(chandle, channelA, ctypes.byref(bufferAMax), ctypes.byref(bufferAMin), nSamples, dataType, waveform, downSampleMode, action)
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assert_pico_ok(status["setDataBuffers"])
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# Run block capture
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# handle = chandle
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# timebase = timebase
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timeIndisposedMs = ctypes.c_double(0)
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# segmentIndex = 0
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# lpReady = None Using IsReady rather than a callback
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# pParameter = None
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status["runBlock"] = ps.psospaRunBlock(chandle, noOfPreTriggerSamples, noOfPostTriggerSamples, timebase, ctypes.byref(timeIndisposedMs), 0, None, None)
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assert_pico_ok(status["runBlock"])
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# Check for data collection to finish using psospaIsReady
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ready = ctypes.c_int16(0)
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check = ctypes.c_int16(0)
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while ready.value == check.value:
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status["isReady"] = ps.psospaIsReady(chandle, ctypes.byref(ready))
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# Get data from scope
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# handle = chandle
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# startIndex = 0
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noOfSamples = ctypes.c_uint64(nSamples)
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# downSampleRatio = 1
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# segmentIndex = 0
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overflow = ctypes.c_int16(0)
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status["getValues"] = ps.psospaGetValues(chandle, 0, ctypes.byref(noOfSamples), 1, downSampleMode, 0, ctypes.byref(overflow))
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assert_pico_ok(status["getValues"])
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# # convert ADC counts data to mV
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adc2mVChAMax = adc2mVV2(bufferAMax, rangeMax, maxADC)
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# Create time data
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time = np.linspace(0, (nSamples -1) * timeInterval.value * 1000000000, nSamples)
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# plot data from channel A and B
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plt.plot(time, bufferAMax[:])
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plt.xlabel('Time (ns)')
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plt.ylabel('Voltage (mV)')
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plt.show()
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# Close the psospa driver device
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status["closeUnit"] = ps.psospaCloseUnit(chandle)
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assert_pico_ok(status["closeUnit"])
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print(status)

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