Copy measurement code from 16T computer

Keithley_2014.py

@@ -0,0 +1,239 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+"""
+
+Sub programs for operating some Keithley instruments
+
+author : Eoin O'Farrell
+email : [email protected]
+last edited : July 2013
+
+Classes for:
+	6430
+	
+	InitializeInstruments
+	ScanInstruments
+	InitializeDataFile
+	WriteDataFile
+	CloseDataFile
+	GraphData
+
+"""
+
+import rpyc
+import visa as visa
+import VisaSubs as VisaSubs
+import string as string
+import re as re
+from collections import namedtuple
+import time
+import math
+import numpy as np
+import threading
+import Queue
+
+######################################################
+# At the moment each of the instruments we use is a
+# seperate class
+#####################################################
+
+class k6430:
+	def __init__(self,address, compliance = 105e-9, median = 0,repetition =1, integration = 1,source = "VOLT",delay = 0.1, trigger = 0):
+		self.Address = address
+		self.Visa = VisaSubs.InitializeGPIB(address,0,term_chars = "\\n")
+		# Other 6430 properties
+		self.Compliance = compliance
+		self.Source = source
+		self.Integration = integration # Defaults to 1
+		self.Median = median # Defaults to 0 (no medianing)
+		self.Repetition = repetition # Defaults to 1 (no averaging)
+		self.Delay = delay # Defaults to 0 (second)
+		self.Trigger = trigger # Trigger delay (defaults to 0)
+		self.Output = False
+		self.Visa.write(":OUTP 0")
+		self.Data = [0.0 ,0.0]
+		self.Sense = []
+		self.RampStep = 0.1
+		self.ColumnNames = "V (V), I (A)"
+
+	######################################
+	# Initialization i.e. writing a load of SCPI
+	#######################################
+
+	def Initialize(self,SkipCompliance = False,SkipMath = False):
+
+		# A bunch of commands to configure the 6430
+		self.Visa.write("*RST")
+		time.sleep(.1)
+		self.Visa.write("".join((":SOUR:FUNC:MODE ",self.Source)))
+		# Configure the auto zero (reference)
+		self.Visa.write(":SYST:AZER:STAT ON")
+		self.Visa.write(":SYST:AZER:CACH:STAT 1")
+		self.Visa.write(":SYST:AZER:CACH:RES")
+
+		# Disable concurrent mode, measure I and V (not R)
+		self.Visa.write(":SENS:FUNC:CONC 1")	
+		if self.Source == "VOLT":
+			self.Sense = "CURR"
+		elif self.Source == "CURR":
+			self.Sense = "VOLT"
+
+		self.Visa.write("".join((":SENS:FUNC:ON ","\"%s\"," % self.Source,"\"%s\"" % self.Sense)))
+		self.Visa.write("".join((":FORM:ELEM ","%s," % self.Source,"%s" % self.Sense)))
+		self.Visa.write("".join((":SENS:",self.Sense,":RANG:AUTO 0")))
+
+		# Set the complicance
+		if not SkipCompliance:
+			self.Visa.write("".join((":SENS:",self.Sense,":RANG 105e-9")))
+			self.Visa.write("".join((":SENS:",self.Sense,":PROT:LEV %.3e" % self.Compliance)))
+
+#		# Set some filters
+		self.Visa.write("".join((":SENS:",self.Sense,":NPLC %.2f" % self.Integration)))
+		if not SkipMath:
+			self.Visa.write(":SENS:AVER:REP:COUN %d" % self.Repetition)
+			self.Visa.write(":SENS:MED:RANK %d" % self.Median)
+
+		self.Visa.write(":SOUR:DEL %.4f" % self.Delay)
+		self.Visa.write(":TRIG:DEL %.4f" % self.Trigger)
+
+		pass
+
+	###########################################
+	# Set the range and compliance
+	#######################################
+
+	def SetRangeCompliance(self, Range = 105, Compliance = 105):
+
+		self.Compliance = Compliance
+		self.Visa.write("".join((":SENS:",self.Sense,":PROT:LEV %.3e" % self.Compliance)))
+
+		if Range:
+			self.Visa.write("".join((":SENS:",self.Sense,":RANG ","%.2e" % Range)))
+		else:
+			self.Visa.write("".join((":SENS:",self.Sense,":RANG:AUTO 1")))
+
+		pass
+
+	##################################################
+	# Read data
+	################################################
+
+	def ReadData(self):
+		Reply = self.Visa.ask(":READ?")
+		self.Data = [float(i) for i in Reply.split(",")[0:2]]
+		pass
+
+
+	##################################################
+	# Set source
+	##################################################
+
+	def Set(self,Level):
+		self.Visa.write("".join((":SOUR:",self.Source," %.4e" % Level)))
+		pass
+
+	#################################################
+	# Switch the output
+	###############################################
+
+	def SwitchOutput(self):
+		self.Output = not self.Output		
+		self.Visa.write("".join((":OUTP:STAT ","%d" % self.Output)))
+		pass
+
+	#################################################
+	# Configure a sweep
+	###############################################
+
+	def ConfigureSweep(self,Start,Stop,Step,Soak = 0):
+		self.Visa.write("".join((":SOUR:",self.Source,":START %.4e" % Start)))
+		self.Visa.write("".join((":SOUR:",self.Source,":STOP %.4e" % Stop)))
+		self.Visa.write("".join((":SOUR:",self.Source,":STEP %.4e" % Step)))		
+		Count = int(1+abs(Stop - Start)/Step)
+		self.Visa.write(":SOUR:SOAK %.4e" % Soak)
+		self.Visa.write("TRIG:COUN %d" % Count)
+		pass
+
+	###################################################
+	# Begin sweep, this doesn't work so well, not recommended
+	#################################################
+
+	def RunConfiguredSweep(self):
+		self.Visa.write(":SOUR:VOLT:MODE SWE")
+		self.Visa.write(":SOUR:SWE:SPAC LIN")
+		self.Visa.write(":SOUR:SWE:RANG AUTO")
+		self.Visa.write(":SOUR:DEL %0.4e" % self.Delay)
+		self.SwitchOutput()
+		pass
+
+
+	######################################################
+	# Manual sweep, this sweep will be run as a separate process
+	# so it doesn't block the program
+	##################################################
+
+	def RunSweep(self,Start,Stop,Step,Wait,Mode = "linear",**kwargs):
+		#self.Visa.write("".join((":SOUR:",self.Source,":MODE FIX")))
+
+		Targets = [Start, Stop]
+
+		for kw in kwargs.keys():
+			if kw == "mid":
+				Mid = kwargs[kw]
+				for i in Mid:
+					Targets.insert(len(Targets)-1,i)
+
+		Voltage = [Start]
+
+		for i in range(1,len(Targets)):
+			Points = int(1+abs(Targets[i]-Targets[i-1])/Step)
+			if Mode == "linear":
+				Voltage = np.hstack([Voltage,np.linspace(Targets[i-1],Targets[i],num = Points)[1:Points]])
+			if Mode == "log":
+				Voltage = np.hstack([Voltage,np.linspace(Targets[i-1],Targets[i],num = Points)[1:Points]])
+
+
+
+#		self.Visa.write("".join((":SOUR:",self.Source," %.4e" % Voltage[0])))
+
+		return Voltage
+
+
+	###################################################
+	# Print a description string 
+	################################################
+
+	def Description(self):
+		DescriptionString = "Keithley6430"
+		for item in vars(self).items():
+			if item[0] == "Repetition" or item[0] == "Median" or item[0] == "Integration" or item[0] == "Address":
+				DescriptionString = ", ".join((DescriptionString,"%s = %.3f" % item))
+			elif item[0] == "Source" or item[0] == "Sense" or item[0] == "Compliance":
+				DescriptionString = ", ".join((DescriptionString,"%s = %s" % item))
+
+
+		DescriptionString = "".join((DescriptionString,"\n"))
+		return DescriptionString
+
+	############################################
+	######### Ramp the source to a final value
+	#########################################
+
+	def Ramp(self,VFinish):
+		if self.Output:
+			self.ReadData()
+		VStart = self.Data[0]
+		N = abs((VFinish-VStart)/self.RampStep)
+		VSweep = np.linspace(VStart,VFinish,num=N,endpoint=True)
+
+		if not self.Output:
+			self.SwitchOutput()
+
+		for i in range(len(VSweep)):
+			self.Set(VSweep[i])
+			time.sleep(0.01)
+
+		self.ReadData()
+		return
+