Create ps3000aBlockAdvancedTriggerExample.py

Author: neil.hamilton

ps3000aExamples/ps3000aBlockAdvancedTriggerExample.py

@@ -0,0 +1,196 @@
+#
+# Copyright (C) 2018 Pico Technology Ltd. See LICENSE file for terms.
+#
+# PS3000A BLOCK MODE EXAMPLE
+# This example opens a 3000a driver device, sets up one channels and a trigger then collects a block of data.
+# This data is then plotted as mV against time in ns.
+
+import ctypes
+from picosdk.ps3000a import ps3000a as ps
+import numpy as np
+import matplotlib.pyplot as plt
+from picosdk.functions import adc2mV, mV2adc, assert_pico_ok
+
+# Create chandle and status ready for use
+status = {}
+chandle = ctypes.c_int16()
+
+# Opens the device/s
+status["openunit"] = ps.ps3000aOpenUnit(ctypes.byref(chandle), None)
+
+try:
+    assert_pico_ok(status["openunit"])
+except:
+
+    # powerstate becomes the status number of openunit
+    powerstate = status["openunit"]
+
+    # If powerstate is the same as 282 then it will run this if statement
+    if powerstate == 282:
+        # Changes the power input to "PICO_POWER_SUPPLY_NOT_CONNECTED"
+        status["ChangePowerSource"] = ps.ps3000aChangePowerSource(chandle, 282)
+        # If the powerstate is the same as 286 then it will run this if statement
+    elif powerstate == 286:
+        # Changes the power input to "PICO_USB3_0_DEVICE_NON_USB3_0_PORT"
+        status["ChangePowerSource"] = ps.ps3000aChangePowerSource(chandle, 286)
+    else:
+        raise
+
+    assert_pico_ok(status["ChangePowerSource"])
+
+# Set up channel A
+# handle = chandle
+# channel = PS3000A_CHANNEL_A = 0
+# enabled = 1
+# coupling type = PS3000A_DC = 1
+# range = PS3000A_10V = 8
+# analogue offset = 0 V
+chARange = 8
+status["setChA"] = ps.ps3000aSetChannel(chandle, 0, 1, 1, chARange, 0)
+assert_pico_ok(status["setChA"])
+
+# Finds the max ADC count
+# Handle = chandle
+# Value = ctypes.byref(maxADC)
+maxADC = ctypes.c_int16()
+status["maximumValue"] = ps.ps3000aMaximumValue(chandle, ctypes.byref(maxADC))
+assert_pico_ok(status["maximumValue"])
+
+# Set an advanced trigger
+adcTriggerLevel = mV2adc(500, chARange, maxADC)
+
+# set trigger channel properties
+# handle = chandle
+channelProperties = ps.PS3000A_TRIGGER_CHANNEL_PROPERTIES(adcTriggerLevel,
+                                                          10,
+                                                          0,
+                                                          10,
+                                                          ps.PS3000A_CHANNEL["PS3000A_CHANNEL_A"])
+nChannelProperties = 1
+# auxOutputEnabled = 0
+autoTriggerMilliseconds = 1000
+status["setTrigProp"] = ps.ps3000aSetTriggerChannelProperties(chandle, ctypes.byref(channelProperties), nChannelProperties, 0, autoTriggerMilliseconds)
+assert_pico_ok(status["setTrigProp"])
+
+# set trigger conditions V2
+# chandle = handle
+conditions = ps.PS3000A_TRIGGER_CONDITIONS_V2(ps.PS3000A_TRIGGER_STATE["PS3000A_CONDITION_TRUE"],
+                                              ps.PS3000A_TRIGGER_STATE["PS3000A_CONDITION_DONT_CARE"],
+                                              ps.PS3000A_TRIGGER_STATE["PS3000A_CONDITION_DONT_CARE"],
+                                              ps.PS3000A_TRIGGER_STATE["PS3000A_CONDITION_DONT_CARE"],
+                                              ps.PS3000A_TRIGGER_STATE["PS3000A_CONDITION_DONT_CARE"],
+                                              ps.PS3000A_TRIGGER_STATE["PS3000A_CONDITION_DONT_CARE"],
+                                              ps.PS3000A_TRIGGER_STATE["PS3000A_CONDITION_DONT_CARE"],
+                                              ps.PS3000A_TRIGGER_STATE["PS3000A_CONDITION_DONT_CARE"])
+nConditions = 1
+status["setTrigCond"] = ps.ps3000aSetTriggerChannelConditionsV2(chandle, ctypes.byref(conditions), nConditions)
+assert_pico_ok(status["setTrigCond"])
+
+# set trigger directions
+# handle = chandle
+channelADirection = ps.PS3000A_THRESHOLD_DIRECTION["PS3000A_RISING"]
+channelBDirection = ps.PS3000A_THRESHOLD_DIRECTION["PS3000A_NONE"]
+channelCDirection = ps.PS3000A_THRESHOLD_DIRECTION["PS3000A_NONE"]
+channelDDirection = ps.PS3000A_THRESHOLD_DIRECTION["PS3000A_NONE"]
+extDirection = ps.PS3000A_THRESHOLD_DIRECTION["PS3000A_NONE"]
+auxDirection = ps.PS3000A_THRESHOLD_DIRECTION["PS3000A_NONE"]
+status["setTrigDir"] = ps.ps3000aSetTriggerChannelDirections(chandle, channelADirection, channelBDirection, channelCDirection, channelDDirection, extDirection, auxDirection)
+assert_pico_ok(status["setTrigDir"])
+
+# Setting the number of sample to be collected
+preTriggerSamples = 40000
+postTriggerSamples = 40000
+maxsamples = preTriggerSamples + postTriggerSamples
+
+# Gets timebase innfomation
+# Handle = chandle
+# Timebase = 2 = timebase
+# Nosample = maxsamples
+# TimeIntervalNanoseconds = ctypes.byref(timeIntervalns)
+# MaxSamples = ctypes.byref(returnedMaxSamples)
+# Segement index = 0
+timebase = 2
+timeIntervalns = ctypes.c_float()
+returnedMaxSamples = ctypes.c_int16()
+status["GetTimebase"] = ps.ps3000aGetTimebase2(chandle, timebase, maxsamples, ctypes.byref(timeIntervalns), 1, ctypes.byref(returnedMaxSamples), 0)
+assert_pico_ok(status["GetTimebase"])
+
+# Creates a overlow location for data
+overflow = ctypes.c_int16()
+# Creates converted types maxsamples
+cmaxSamples = ctypes.c_int32(maxsamples)
+
+# Starts the block capture
+# Handle = chandle
+# Number of prTriggerSamples
+# Number of postTriggerSamples
+# Timebase = 2 = 4ns (see Programmer's guide for more information on timebases)
+# time indisposed ms = None (This is not needed within the example)
+# Segment index = 0
+# LpRead = None
+# pParameter = None
+status["runblock"] = ps.ps3000aRunBlock(chandle, preTriggerSamples, postTriggerSamples, timebase, 1, None, 0, None, None)
+assert_pico_ok(status["runblock"])
+
+# Create buffers ready for assigning pointers for data collection
+bufferAMax = (ctypes.c_int16 * maxsamples)()
+bufferAMin = (ctypes.c_int16 * maxsamples)() # used for downsampling which isn't in the scope of this example
+
+# Setting the data buffer location for data collection from channel A
+# Handle = Chandle
+# source = ps3000A_channel_A = 0
+# Buffer max = ctypes.byref(bufferAMax)
+# Buffer min = ctypes.byref(bufferAMin)
+# Buffer length = maxsamples
+# Segment index = 0
+# Ratio mode = ps3000A_Ratio_Mode_None = 0
+status["SetDataBuffers"] = ps.ps3000aSetDataBuffers(chandle, 0, ctypes.byref(bufferAMax), ctypes.byref(bufferAMin), maxsamples, 0, 0)
+assert_pico_ok(status["SetDataBuffers"])
+
+# Creates a overlow location for data
+overflow = (ctypes.c_int16 * 10)()
+# Creates converted types maxsamples
+cmaxSamples = ctypes.c_int32(maxsamples)
+
+# Checks data collection to finish the capture
+ready = ctypes.c_int16(0)
+check = ctypes.c_int16(0)
+while ready.value == check.value:
+    status["isReady"] = ps.ps3000aIsReady(chandle, ctypes.byref(ready))
+
+# Handle = chandle
+# start index = 0
+# noOfSamples = ctypes.byref(cmaxSamples)
+# DownSampleRatio = 0
+# DownSampleRatioMode = 0
+# SegmentIndex = 0
+# Overflow = ctypes.byref(overflow)
+
+status["GetValues"] = ps.ps3000aGetValues(chandle, 0, ctypes.byref(cmaxSamples), 0, 0, 0, ctypes.byref(overflow))
+assert_pico_ok(status["GetValues"])
+
+# Converts ADC from channel A to mV
+adc2mVChAMax =  adc2mV(bufferAMax, chARange, maxADC)
+
+# Creates the time data
+time = np.linspace(0, (cmaxSamples.value) * timeIntervalns.value, cmaxSamples.value)
+
+# Plots the data from channel A onto a graph
+plt.plot(time, adc2mVChAMax[:])
+plt.xlabel('Time (ns)')
+plt.ylabel('Voltage (mV)')
+plt.show()
+
+# Stops the scope
+# Handle = chandle
+status["stop"] = ps.ps3000aStop(chandle)
+assert_pico_ok(status["stop"])
+
+# Closes the unit
+# Handle = chandle
+status["close"] = ps.ps3000aCloseUnit(chandle)
+assert_pico_ok(status["close"])
+
+# Displays the staus returns
+print(status)
+