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"""
Created by Eugeniy E. Mikhailov 2021/11/29
"""
from qolab.hardware.scope import ScopeSCPI
from qolab.hardware.scpi import response2numStr
from qolab.data.trace import Trace, TraceXY
import numpy as np
import scipy.signal
class SDS1104X(ScopeSCPI):
""" Siglent SDS1104x scope """
vertDivOnScreen = 10
horizDivOnScreen = 14
def __init__(self, resource):
super().__init__(resource)
self.config['Device model'] = 'SDS1104X'
self.resource.read_termination='\n'
self.numberOfChannels = 4
self.maxRequiredPoints = 1000; # desired number of points per channel, can return twice more
def mean(self, chNum):
# get mean on a specific channel calculated by scope
# PAVA stands for PArameter VAlue
qstr = f'C{chNum}:PAVA? MEAN'
rstr = self.query(qstr);
# reply is in the form 'C1:PAVA MEAN,3.00E-02V'
prefix, numberString, unit = response2numStr(rstr, firstSeparator=',', unit='V')
return(float(numberString))
def getAvailableNumberOfPoints(self, chNum):
if chNum != 1 and chNum != 3:
# for whatever reason 'SAMPLE_NUM' fails for channel 2 and 4
chNum = 1
qstr = f'SAMPLE_NUM? C{chNum}'
rstr = self.query(qstr)
# reply is in the form 'SANU 7.00E+01pts'
prefix, numberString, unit = response2numStr(rstr, firstSeparator=' ', unit='pts')
return(int(float(numberString)))
def getSampleRate(self):
rstr = self.query('SAMPLE_RATE?');
# expected reply is like 'SARA 1.00E+09Sa/s'
prefix, numberString, unit = response2numStr(rstr, firstSeparator=' ', unit='Sa/s')
return(int(float(numberString)))
def calcSparsingAndNumPoints(self, availableNpnts=None, maxRequiredPoints=None):
if availableNpnts is None:
# using channel 1 to get availableNpnts
availableNpnts = self.getAvailableNumberOfPoints(1)
if maxRequiredPoints is None:
maxRequiredPoints = self.maxRequiredPoints
if availableNpnts <= maxRequiredPoints*2:
Npnts = availableNpnts
sparsing = 1
else:
sparsing = int(np.floor(availableNpnts/maxRequiredPoints))
Npnts = int(np.floor(availableNpnts/sparsing))
return(sparsing, Npnts, availableNpnts, maxRequiredPoints)
def getRawWaveform(self, chNum, availableNpnts=None, maxRequiredPoints=None, decimate=True):
"""
If decimate is used, we get all available points and then low-pass filter them.
The result is less noisy. But transfer time from the instrument is longer.
If decimate=False we might see aliasing, if there is a high frequency noise
and sparsing > 1
"""
(sparsing, Npnts, availableNpnts, maxRequiredPoints) = self.calcSparsingAndNumPoints(availableNpnts, maxRequiredPoints)
if (sparsing == 1 and Npnts == availableNpnts) or decimate:
# we are getting all of it
cstr = f'WAVEFORM_SETUP NP,0,FP,0,SP,{sparsing}'
# technically when we know Npnts and sparsing
# we can use command from the follow up 'else' clause
else:
# we just ask every point with 'sparsing' interval
# fast to grab but we could do better with more advance decimate
# method, which allow better precision for the price of longer acquisition time
cstr = f'WAVEFORM_SETUP SP,{sparsing},NP,{Npnts},FP,0'
# Note: it is not enough to provide sparsing (SP),
# number of points (NP) needed to be calculated properly too!
# From the manual
# WAVEFORM_SETUP SP,<sparsing>,NP,<number>,FP,<point>
# SP Sparse point. It defines the interval between data points.
# For example:
# SP = 0 sends all data points.
# SP = 1 sends all data points.
# SP = 4 sends every 4th data point
# NP — Number of points. It indicates how many points should be transmitted.
# For example:
# NP = 0 sends all data points.
# NP = 50 sends a maximum of 50 data points.
# FP — First point. It specifies the address of the first data point to be sent.
# For example:
# FP = 0 corresponds to the first data point.
# FP = 1 corresponds to the second data point
self.write(cstr)
qstr = f'C{chNum}:WAVEFORM? DAT2'
wfRaw=self.query_binary_values(qstr, datatype='b', header_fmt='ieee', container=np.array, chunk_size=(Npnts+100))
# expected full reply: 'C1:WF DAT2,#9000000140.........'
trRaw = Trace(f'Ch{chNum}')
trRaw.values = wfRaw.reshape(wfRaw.size,1)
if decimate and sparsing != 1:
numtaps = 3; # not sure it is the best case
trRaw.values = scipy.signal.decimate(trRaw.values, sparsing, 3, axis=0)
trRaw.config['unit'] = 'Count'
trRaw.config['tags']['Decimate'] = decimate
return(trRaw, availableNpnts, Npnts)
def getChanVoltsPerDiv(self, chNum):
qstr = f'C{chNum}:VDIV?'
rstr = self.query(qstr)
# expected reply to query: 'C1:VDIV 1.04E+00V'
prefix, numberString, unit = response2numStr(rstr, firstSeparator=' ', unit='V')
return(float(numberString))
def setChanVoltsPerDiv(self, chNum, vPerDiv):
cstr = f'C{chNum}:VDIV {vPerDiv}'
self.write(cstr)
# if out of range, the VAB bit (bit 2) in the STB register to be set
def getChanOffset(self, chNum):
qstr = f'C{chNum}:OFST?'
rstr = self.query(qstr)
# expected reply to query: 'C1:OFST -1.27E+00V'
prefix, numberString, unit = response2numStr(rstr, firstSeparator=' ', unit='V')
return(float(numberString))
def getTimePerDiv(self):
qstr = f'TDIV?'
rstr = self.query(qstr)
# expected reply to query: 'TDIV 2.00E-08S'
prefix, numberString, unit = response2numStr(rstr, firstSeparator=' ', unit='S')
return(float(numberString))
def setTimePerDiv(self, timePerDiv):
cstr = f'TDIV {timePerDiv}'
self.write(cstr)
# if out of range, the VAB bit (bit 2) in the STB register to be set
def getTrigDelay(self):
qstr = f'TRIG_DELAY?'
rstr = self.query(qstr)
# expected reply to query: 'TRDL -0.00E+00S'
prefix, numberString, unit = response2numStr(rstr, firstSeparator=' ', unit='S')
return(float(numberString))
def getWaveform(self, chNum, availableNpnts=None, maxRequiredPoints=None, decimate=True):
"""
For decimate use see getRawWaveform. In short decimate=True is slower but more precise.
"""
trRaw, availableNpnts, Npnts = self.getRawWaveform(chNum, availableNpnts=availableNpnts, maxRequiredPoints=maxRequiredPoints, decimate=decimate)
VoltageOffset = self.getChanOffset(chNum)
VoltsPerDiv = self.getChanVoltsPerDiv(chNum)
tr = trRaw
tr.values = trRaw.values * VoltsPerDiv * self.vertDivOnScreen/250 -VoltageOffset
tr.config['unit'] = 'Volt'
tr.config['tags']['VoltageOffset'] = VoltageOffset
tr.config['tags']['VoltsPerDiv'] = VoltsPerDiv
return(tr, availableNpnts)
def getTimeTrace(self, availableNpnts=None, maxRequiredPoints=None):
(sparsing, Npnts, availableNpnts, maxRequiredPoints) = self.calcSparsingAndNumPoints(availableNpnts, maxRequiredPoints)
sampleRate = self.getSampleRate()
timePerDiv = self.getTimePerDiv()
trigDelay = self.getTrigDelay()
if Npnts is None and sparsing is None:
# using channel 1 as reference
Npnts = self.getAvailableNumberOfPoints(1)
tval = np.arange(Npnts) / sampleRate * sparsing;
tval = tval - timePerDiv * self.horizDivOnScreen/2 - trigDelay
t = Trace('time')
t.values = tval.reshape(tval.size,1)
t.config['unit'] = 'S'
t.config['tags']['TimePerDiv'] = timePerDiv
t.config['tags']['TrigDelay'] = trigDelay
t.config['tags']['SampleRate'] = sampleRate
t.config['tags']['AvailableNPnts'] = availableNpnts
t.config['tags']['Npnts'] = availableNpnts
t.config['tags']['Sparsing'] = sparsing
return(t)
def getTrace(self, chNum, availableNpnts=None, maxRequiredPoints=None, decimate=True):
wfVoltage, availableNpnts = self.getWaveform( chNum, availableNpnts=availableNpnts, maxRequiredPoints=maxRequiredPoints, decimate=decimate)
t = self.getTimeTrace(availableNpnts=availableNpnts, maxRequiredPoints=maxRequiredPoints)
tr = TraceXY( f'Ch{chNum}' )
tr.x = t
tr.y = wfVoltage
return( tr )
if __name__ == '__main__':
import pyvisa
print("testing")
rm = pyvisa.ResourceManager()
print(rm.list_resources())
instr=rm.open_resource('TCPIP::192.168.0.61::INSTR')
scope = SDS1104X(instr)
print(f'ID: {scope.idn}')
print(f'Ch1 mean: {scope.mean(1)}')
print(f'Ch1 available points: {scope.getAvailableNumberOfPoints(1)}')
print(f'Sample Rate: {scope.getSampleRate()}')
print(f'Time per Div: {scope.getTimePerDiv()}')
print(f'Ch1 Volts per Div: {scope.getChanVoltsPerDiv(1)}')
print(f'Ch1 Voltage Offset: {scope.getChanOffset(1)}')
print('------ Header start -------------')
print(str.join('\n', scope.getHeader()))
print('------ Header ends -------------')
ch1 = scope.getTrace(1)
traces = scope.getAllTraces()
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