class IviGui:
def __init__(self, master):
self.master = master
master.title("U2001A power measurement")
# Label and Entry for inputting relative/attenuator value
self.atten = Label(master, text="Relative (dB):")
self.atten.grid(row=1, column=1)
self.entry = Entry(master)
self.entry.insert(0, '0')
self.entry.grid(row=1, column=2)
# Main display label. Shows relative measurement with dot during updates
self.label = Label(master,
text=" \n-NaN dBm",
font=("Arial", 32),
height=3,
width=20)
self.label.grid(row=2, column=1, columnspan=2)
# Smaller secondary display to show real measurement by device
self.label2 = Label(master, text=" \n-NaN dBm", font=("Arial", 16))
self.label2.grid(row=3, column=1, columnspan=2)
print usbtmc.list_resources() # List USBTMC resources to connect to.
self.instr = usbtmc.Instrument(
'USB::10893::11032::INSTR'
) # Your device to connect to. Pick from the list.
self.instr.timeout = 60 * 1000 # Some devices are slow, some configurations are slow, timeout in ms.
print self.instr.ask(
"*IDN?"
) # Print out what device itself thinks its name is for validation.
# Keysight U2001A trigger setup - free running trigger
self.instr.write("INIT[1]:CONT 1")
self.instr.write("TRIG[1]:SOUR IMM")
# Init the variables
self.measurement = -100
self.original_background = self.entry.cget("background")
# Start first measurement
self.update()
# This method polls the device and updates display. Polling can take long time.
def update(self):
self.measurement = self.instr.ask("MEAS?")
#print "%.2f" % float(self.measurement) # Debug printout to check the connection.
self.update_number(True)
self.label.after(100, self.remove_dot)
# 100 ms after getting a measurement from the device, remove the dot above the measurement.
# This provided clear indication to user about when the data was updated.
def remove_dot(self):
self.update_number(False)
self.label.after(100, self.update)
# Deal with getting the relative number from the Entry and updating all the displays.
def update_number(self, dot=False):
try:
relative_value = float(self.entry.get())
self.entry.config(background=self.original_background)
if dot:
self.label.config(text=".\n%.2f dBm" %
(float(self.measurement) - relative_value))
else:
self.label.config(text=" \n%.2f dBm" %
(float(self.measurement) - relative_value))
# If the relative box shows gibberish, just display the measurement.
except ValueError:
self.entry.config(background="#A44")
if dot:
self.label.config(text=".\n%.2f dBm" % float(self.measurement))
else:
self.label.config(text=" \n%.2f dBm" % float(self.measurement))
self.label2.config(text="%.2f dBm" % float(self.measurement))
