Python 3

OscScreenGrabLAN.py

@@ -1,10 +1,10 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 
 from telnetlib_receive_all import Telnet
 from Rigol_functions import *
 import time
 from PIL import Image
-import StringIO
+import io
 import sys
 import os
 import platform
@@ -74,35 +74,35 @@
 
 
 def print_help():
-    print
-    print "Usage:"
-    print "    " + "python " + script_name + " png|bmp|csv [oscilloscope_IP [save_path]]"
-    print
-    print "Usage examples:"
-    print "    " + "python " + script_name + " png"
-    print "    " + "python " + script_name + " csv 192.168.1.3"
-    print
-    print "The following usage cases are not yet implemented:"
-    print "    " + "python " + script_name + " bmp 192.168.1.3 my_place_for_captures"
-    print
-    print "This program captures either the waveform or the whole screen"
-    print "    of a Rigol DS1000Z series oscilloscope, then save it on the computer"
-    print "    as a CSV, PNG or BMP file with a timestamp in the file name."
-    print
-    print "    The program is using LXI protocol, so the computer"
-    print "    must have LAN connection with the oscilloscope."
-    print "    USB and/or GPIB connections are not used by this software."
-    print
-    print "    No VISA, IVI or Rigol drivers are needed."
-    print
+    print()
+    print("Usage:")
+    print("    " + "python " + script_name + " png|bmp|csv [oscilloscope_IP [save_path]]")
+    print()
+    print("Usage examples:")
+    print("    " + "python " + script_name + " png")
+    print("    " + "python " + script_name + " csv 192.168.1.3")
+    print()
+    print("The following usage cases are not yet implemented:")
+    print("    " + "python " + script_name + " bmp 192.168.1.3 my_place_for_captures")
+    print()
+    print("This program captures either the waveform or the whole screen")
+    print("    of a Rigol DS1000Z series oscilloscope, then save it on the computer")
+    print("    as a CSV, PNG or BMP file with a timestamp in the file name.")
+    print()
+    print("    The program is using LXI protocol, so the computer")
+    print("    must have LAN connection with the oscilloscope.")
+    print("    USB and/or GPIB connections are not used by this software.")
+    print()
+    print("    No VISA, IVI or Rigol drivers are needed.")
+    print()
 
 # Read/verify file type
 if len(sys.argv) <= 1:
     print_help()
     sys.exit("Warning - wrong command line parameters.")
 elif sys.argv[1].lower() not in ["png", "bmp", "csv"]:
     print_help()
-    print "This file type is not supported: ", sys.argv[1]
+    print("This file type is not supported: ", sys.argv[1])
     sys.exit("ERROR")
 
 file_format = sys.argv[1].lower()
@@ -118,10 +118,10 @@ def print_help():
     response = os.system("ping -c 1 " + IP_DS1104Z + " > /dev/null")
 
 if response != 0:
-    print
-    print "WARNING! No response pinging " + IP_DS1104Z
-    print "Check network cables and settings."
-    print "You should be able to ping the oscilloscope."
+    print()
+    print("WARNING! No response pinging " + IP_DS1104Z)
+    print("Check network cables and settings.")
+    print("You should be able to ping the oscilloscope.")
 
 # Open a modified telnet session
 # The default telnetlib drops 0x00 characters,
@@ -131,40 +131,39 @@ def print_help():
 
 # Check if instrument is set to accept LAN commands
 if instrument_id == "command error":
-    print "Instrument reply:", instrument_id
-    print "Check the oscilloscope settings."
-    print "Utility -> IO Setting -> RemoteIO -> LAN must be ON"
+    print("Instrument reply:", instrument_id)
+    print("Check the oscilloscope settings.")
+    print("Utility -> IO Setting -> RemoteIO -> LAN must be ON")
     sys.exit("ERROR")
 
 # Check if instrument is indeed a Rigol DS1000Z series
 id_fields = instrument_id.split(",")
 if (id_fields[company] != "RIGOL TECHNOLOGIES") or \
         (id_fields[model][:3] != "DS1") or (id_fields[model][-1] != "Z"):
-    print "Found instrument model", "'" + id_fields[model] + "'", "from", "'" + id_fields[company] + "'"
-    print "WARNING: No Rigol from series DS1000Z found at", IP_DS1104Z
-    print
-    typed = raw_input("ARE YOU SURE YOU WANT TO CONTINUE? (No/Yes):")
+    print("Found instrument model", "'" + id_fields[model] + "'", "from", "'" + id_fields[company] + "'")
+    print("WARNING: No Rigol from series DS1000Z found at", IP_DS1104Z)
+    print()
+    typed = input("ARE YOU SURE YOU WANT TO CONTINUE? (No/Yes):")
     if typed != 'Yes':
         sys.exit('Nothing done. Bye!')
 
-print "Instrument ID:",
-print instrument_id
+print("Instrument ID:", instrument_id)
 
 # Prepare filename as C:\MODEL_SERIAL_YYYY-MM-DD_HH.MM.SS
 timestamp = time.strftime("%Y-%m-%d_%H.%M.%S", time.localtime())
 filename = path_to_save + id_fields[model] + "_" + id_fields[serial] + "_" + timestamp
 
 if file_format in ["png", "bmp"]:
     # Ask for an oscilloscope display print screen
-    print "Receiving screen capture..."
-    buff = command(tn, ":DISP:DATA?")
+    print("Receiving screen capture...")
+    buff = command_bin(tn, ":DISP:DATA?")
 
     expectedBuffLen = expected_buff_bytes(buff)
     # Just in case the transfer did not complete in the expected time, read the remaining 'buff' chunks
     while len(buff) < expectedBuffLen:
         logging.warning("Received LESS data then expected! (" +
                         str(len(buff)) + " out of " + str(expectedBuffLen) + " expected 'buff' bytes.)")
-        tmp = tn.read_until("\n", smallWait)
+        tmp = tn.read_until(b"\n", smallWait)
         if len(tmp) == 0:
             break
         buff += tmp
@@ -181,16 +180,16 @@ def print_help():
     buff = buff[tmcHeaderLen: tmcHeaderLen+expectedDataLen]
 
     # Save as PNG or BMP according to file_format
-    im = Image.open(StringIO.StringIO(buff))
+    im = Image.open(io.BytesIO(buff))
     im.save(filename + "." + file_format, file_format)
-    print "Saved file:", "'" + filename + "." + file_format + "'"
+    print("Saved file:", "'" + filename + "." + file_format + "'")
 
 # TODO: Change WAV:FORM from ASC to BYTE
 elif file_format == "csv":
     # Put the scope in STOP mode - for the moment, deal with it by manually stopping the scope
     # TODO: Add command line switch and code logic for 1200 vs ALL memory data points
     # tn.write("stop")
-    # response = tn.read_until("\n", 1)
+    # response = tn.read_until(b"\n", 1)
 
     # Scan for displayed channels
     chanList = []
@@ -214,7 +213,7 @@ def print_help():
 
     # for each active channel
     for channel in chanList:
-        print
+        print()
 
         # Set WAVE parameters
         command(tn, ":WAV:SOUR " + channel)
@@ -226,15 +225,15 @@ def print_help():
             command(tn, ":WAV:STOP 1200")
 
         buff = ""
-        print "Data from channel '" + str(channel) + "', points " + str(1) + "-" + str(1200) + ": Receiving..."
+        print("Data from channel '" + str(channel) + "', points " + str(1) + "-" + str(1200) + ": Receiving...")
         buffChunk = command(tn, ":WAV:DATA?")
 
         # Just in case the transfer did not complete in the expected time
         while buffChunk[-1] != "\n":
             logging.warning("The data transfer did not complete in the expected time of " +
                             str(smallWait) + " second(s).")
 
-            tmp = tn.read_until("\n", smallWait)
+            tmp = tn.read_until(b"\n", smallWait)
             if len(tmp) == 0:
                 break
             buffChunk += tmp
@@ -278,6 +277,6 @@ def print_help():
     scr_file.write(csv_buff)
     scr_file.close()
 
-    print "Saved file:", "'" + filename + "." + file_format + "'"
+    print("Saved file:", "'" + filename + "." + file_format + "'")
 
 tn.close()

Rigol_functions.py

@@ -1,4 +1,4 @@
-import pip
+import pkg_resources
 import sys
 import logging
 
@@ -8,7 +8,7 @@
 def log_running_python_versions():
     logging.info("Python version: " + str(sys.version) + ", " + str(sys.version_info))  # () required in Python 3.
 
-    installed_packages = pip.get_installed_distributions()
+    installed_packages = pkg_resources.working_set
     installed_packages_list = sorted(["%s==%s" % (i.key, i.version) for i in installed_packages])
     logging.info("Installed Python modules: " + str(installed_packages_list))
 
@@ -18,29 +18,46 @@ def command(tn, scpi):
     answer_wait_s = 1
     response = ""
     while response != "1\n":
-        tn.write("*OPC?\n")  # previous operation(s) has completed ?
+        tn.write(b"*OPC?\n")  # previous operation(s) has completed ?
         logging.info("Send SCPI: *OPC? # May I send a command? 1==yes")
-        response = tn.read_until("\n", 1)  # wait max 1s for an answer
+        response = tn.read_until(b"\n", 1).decode()  # wait max 1s for an answer
         logging.info("Received response: " + response)
 
-    tn.write(scpi + "\n")
+    tn.write(scpi.encode() + b"\n")
     logging.info("Sent SCPI: " + scpi)
-    response = tn.read_until("\n", answer_wait_s)
+    response = tn.read_until(b"\n", answer_wait_s).decode()
     logging.info("Received response: " + response)
     return response
 
 
+def command_bin(tn, scpi):
+    logging.info("SCPI to be sent: " + scpi)
+    answer_wait_s = 1
+    response = b""
+    while response != b"1\n":
+        tn.write(b"*OPC?\n")  # previous operation(s) has completed ?
+        logging.info("Send SCPI: *OPC? # May I send a command? 1==yes")
+        response = tn.read_until(b"\n", 1)  # wait max 1s for an answer
+        logging.info("Received response: " + repr(response))
+
+    tn.write(scpi.encode() + b"\n")
+    logging.info("Sent SCPI: " + scpi)
+    response = tn.read_until(b"\n", answer_wait_s)
+    logging.info("Received response: " + repr(response))
+    return response
+
+
 # first TMC byte is '#'
 # second is '0'..'9', and tells how many of the next ASCII chars
 #   should be converted into an integer.
 #   The integer will be the length of the data stream (in bytes)
 # after all the data bytes, the last char is '\n'
 def tmc_header_bytes(buff):
-    return 2 + int(buff[1])
+    return 2 + int(buff[1:2].decode())
 
 
 def expected_data_bytes(buff):
-    return int(buff[2:tmc_header_bytes(buff)])
+    return int(buff[2:tmc_header_bytes(buff)].decode())
 
 
 def expected_buff_bytes(buff):