Basic Script

This script shows a few commonly-used programming steps.

Example Script

basics.py

#!python3

"""This program illustrates a few commonly-used programming
features of your Infiniium XR8 oscilloscope.
"""

# Import modules.
import pyvisa
import struct
import sys
import platformdirs

# Global variables.
# oscilloscope_visa_address = "TCPIP0::lab-pyr-p2-13.cos.is.keysight.com::inst0::INSTR"
oscilloscope_visa_address = "TCPIP0::localhost::hislip0,4880::INSTR"
timeout = 20000  # 20 seconds.
scope_base_directory = "%USER_DATA_DIR%\\"
local_base_directory = f"{platformdirs.user_documents_dir()}\\"


def initialize():
    """Initialize:"""

    # Clear status.
    Infiniium.write("*CLS")

    # Get and display the device's *IDN? string.
    idn_string = Infiniium.query("*IDN?").strip()
    print(f"Identification string: '{idn_string}'")

    # Load the default setup.
    Infiniium.write("*RST")

    # Stop acquisitions and clear the display.
    Infiniium.write(":ACQuire:STOP")
    Infiniium.write(":ACQuire:CDISplay")


def set_up():
    """Set up:"""

    # Set probe attenuation factor.
    # Infiniium.write(":CHANnel1:PROBe:DB 1.0")
    qresult = Infiniium.query(":CHANnel1:PROBe:DB?").strip()
    print(f"Channel 1 probe attenuation factor: {qresult}")

    # Use auto-scale to automatically set up oscilloscope.
    print("Autoscale.")
    Infiniium.query(":SYSTem:AUToscale;*OPC?")

    # Stop acquisitions and clear the display.
    Infiniium.write(":ACQuire:STOP")
    Infiniium.write(":ACQuire:CDISplay")

    # Set trigger mode.
    Infiniium.write(":TRIGger:MODE EDGE")
    qresult = Infiniium.query(":TRIGger:MODE?").strip()
    print(f"Trigger mode: {qresult}")

    # Set EDGE trigger parameters.
    Infiniium.write(":TRIGger:EDGE:SOURce CHANnel1")
    qresult = Infiniium.query(":TRIGger:EDGE:SOURce?").strip()
    print(f"Trigger edge source: {qresult}")

    Infiniium.write(":TRIGger:CHANnel1:LEVel 150E-3")
    qresult = Infiniium.query(":TRIGger:CHANnel1:LEVel?").strip()
    print(f"Trigger level, channel 1: {qresult}")

    Infiniium.write(":TRIGger:EDGE:SLOPe POSitive")
    qresult = Infiniium.query(":TRIGger:EDGE:SLOPe?").strip()
    print(f"Trigger edge slope: {qresult}")

    # Save oscilloscope setup.
    setup_file = f"{scope_base_directory}setup.seti"
    Infiniium.write(f':DISK:SETup:SAVE "{setup_file}"')
    print(f"Setup saved to: {setup_file}")

    # Change oscilloscope settings with individual commands:

    # Set vertical scale and offset.
    Infiniium.write(":CHANnel1:YSCale 0.1")
    qresult = float(Infiniium.query(":CHANnel1:YSCale?"))
    print(f"Channel 1 vertical scale: {qresult:f}")

    Infiniium.write(":CHANnel1:YOFFset 0.0")
    qresult = float(Infiniium.query(":CHANnel1:YOFFset?"))
    print(f"Channel 1 offset: {qresult:f}")

    # Set horizontal scale and offset.
    Infiniium.write(":TIMebase:SCALe 200e-6")
    qresult = Infiniium.query(":TIMebase:SCALe?").strip()
    print(f"Timebase scale: {qresult}")

    Infiniium.write(":TIMebase:POSition 0.0")
    qresult = Infiniium.query(":TIMebase:POSition?").strip()
    print(f"Timebase position: {qresult}")

    # Set the acquisition mode.
    Infiniium.write(":ACQuire:SMODe NORMal")
    qresult = Infiniium.query(":ACQuire:SMODe?").strip()
    print(f"Acquire mode: {qresult}")

    # Or, set up oscilloscope by loading a previously saved setup.
    Infiniium.write(f':DISK:SETup:RECall "{setup_file}"')
    print(f"Setup recalled from: {setup_file}")


def capture():
    """Capture:"""

    # Set the desired number of waveform points,
    # and capture an acquisition.
    Infiniium.write(":ACQuire:POINts:AUTO OFF")
    Infiniium.write(":ACQuire:POINts 2048")
    Infiniium.write(":TIMebase:INTerpolate:AUTO OFF")
    Infiniium.write(":TIMebase:INTerpolate:METHod NONE")
    Infiniium.query(":ACQuire:SINGle;*OPC?")


def analyze():
    """Analyze:"""

    # Make measurements.
    Infiniium.write(":MEASure:HORizontal:FREQuency:SOURce CHANnel1")
    qresult = Infiniium.query(":MEASure:HORizontal:FREQuency:SOURce?").strip()
    print(f"Measure horizontal frequency source: {qresult}")

    Infiniium.write(":MEASure:HORizontal:FREQuency")
    qresult = Infiniium.query(":MEASure:HORizontal:FREQuency?").strip()
    print(f"Measured frequency on channel 1: {qresult}")

    Infiniium.write(":MEASure:VERTical:VAMPlitude:SOURce CHANnel1")
    qresult = Infiniium.query(":MEASure:VERTical:VAMPlitude:SOURce?").strip()
    print(f"Measure vertical amplitude source: {qresult}")

    Infiniium.write(":MEASure:VERTical:VAMPlitude")
    qresult = Infiniium.query(":MEASure:VERTical:VAMPlitude?").strip()
    print(f"Measured vertical amplitude on channel 1: {qresult}")

    # Download the screen image.
    screen_bytes = Infiniium.query_binary_values(
        ":DISPlay:DATA? PNG", datatype="s", container=bytes
    )

    # Save display data values to file.
    image_file = f"{local_base_directory}screen_image.png"
    f = open(image_file, "wb")
    f.write(screen_bytes)
    f.close()
    print(f"Screen image written to {image_file}.")

    # Download waveform data.

    # Get the waveform type.
    qresult = Infiniium.query(":ACQuire:SMODe?").strip()
    print(f"Waveform type: {qresult}")

    # Get the number of waveform points.
    qresult = Infiniium.query(":WAVeform:YFORmat:POINts?").strip()
    print(f"Waveform points: {qresult}")

    # Set the waveform source.
    Infiniium.write(":WAVeform:SOURce CHANnel1")
    qresult = Infiniium.query(":WAVeform:SOURce?").strip()
    print(f"Waveform source: {qresult}")

    # Specify the byte order in WORD data.
    Infiniium.write(":SYSTem:BORDer LENDian")
    qresult = Infiniium.query(":SYSTem:BORDer?").strip()
    print(f"Waveform byte order for WORD data: {qresult}")

    # Get numeric values for later calculations.
    x_increment = float(Infiniium.query(":WAVeform:YFORmat:XINCrement?"))
    print(f"Waveform X increment: {x_increment:f}")
    x_origin = float(Infiniium.query(":WAVeform:YFORmat:XORigin?"))
    print(f"Waveform X origin: {x_origin:f}")
    y_increment = float(Infiniium.query(":WAVeform:YFORmat:WORD:ENCoding:YINCrement?"))
    print(f"Waveform Y increment: {y_increment:f}")
    y_origin = float(Infiniium.query(":WAVeform:YFORmat:WORD:ENCoding:YORigin?"))
    print(f"Waveform Y origin: {y_origin:f}")

    # Get the waveform data.
    # Infiniium.write(":WAVeform:STReaming OFF")
    data_bytes = Infiniium.query_binary_values(
        ":WAVeform:YFORmat:WORD:YDATa?", datatype="s", container=bytes
    )
    data_bytes_length = len(data_bytes)
    print(f"Byte count: {data_bytes_length}")

    block_points = data_bytes_length / 2

    # Unpack or split into list of data values.
    values = struct.unpack("%dh" % block_points, data_bytes)
    print(f"Number of data values: {len(values)}")

    # Save waveform data values to CSV file.
    wfm_data_file = f"{local_base_directory}waveform_data.csv"
    f = open(wfm_data_file, "w")

    for i in range(0, len(values) - 1):
        time_val = x_origin + (i * x_increment)
        voltage = (values[i] * y_increment) + y_origin
        f.write(f"{time_val:E}, {voltage:f}\n")

    f.close()
    print(f"Waveform format WORD data written to {wfm_data_file}.")


def exit_program():
    """Exit program."""

    # Close connection to oscilloscope.
    sys.stdout.write("Closing oscilloscope connection.\n")
    Infiniium.write(":SYSTem:GTLocal")  # Unlock GUI.
    Infiniium.clear()  # Clear oscilloscope communications interface.
    Infiniium.close()  # Close communications interface to oscilloscope.
    rm.close()  # Close resource manager.
    print("End of program.")
    sys.exit()


def check_error_queue(when):
    """Check error queue."""

    errors_found = False
    while True:
        # Keep reading errors until "No error".
        error_string = Infiniium.query(":SYSTem:ERRor:NEXT? DIAGnostic")
        if error_string:  # If there is an error string value.

            if error_string.find("0,", 0, 2) == -1:  # Not "No error".
                errors_found = True
                print(f"ERROR: {error_string}")

            else:  # "No error"
                break

        else:  # :SYSTem:ERRor:NEXT? DIAGnostic should always return string.
            errors_found = True
            print("ERROR: :SYSTem:ERRor:NEXT? DIAGnostic returned nothing.")
            break

    if errors_found:
        print(f"Exited because error(s) found when: '{when}'")
        exit_program()


# ==========================================================
# Main program:
# ==========================================================

# Connect and initialize oscilloscope.
rm = pyvisa.ResourceManager("C:\\Windows\\System32\\visa64.dll")
try:
    Infiniium = rm.open_resource(oscilloscope_visa_address)
except Exception:
    print(
        f"Unable to connect to oscilloscope at {oscilloscope_visa_address}. Aborting program."
    )
    sys.exit()

Infiniium.timeout = timeout  # Set global timeout.
Infiniium.clear()  # Clear the instrument bus.
# Lock GUI happens automatically.

# Initialize the oscilloscope, capture data, and analyze.
initialize()
set_up()
capture()
analyze()

# Check error queue.
check_error_queue("End of program")

# Exit program.
exit_program()