example script for using the live streaming servers

Documentation/UserManual/SCPI_Examples/capture_live_data.py

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+#!/usr/bin/env python3
+
+import time
+from libreVNA import libreVNA
+
+# Create the control instance
+vna = libreVNA('localhost', 19542)
+
+# Quick connection check (should print "LibreVNA-GUI")
+print(vna.query("*IDN?"))
+
+# Make sure we are connecting to a device (just to be sure, with default settings the LibreVNA-GUI auto-connects)
+vna.cmd(":DEV:CONN")
+dev = vna.query(":DEV:CONN?")
+if dev == "Not connected":
+    print("Not connected to any device, aborting")
+    exit(-1)
+else:
+    print("Connected to "+dev)
+
+# Capture live data as it is coming in. Stop acquisition for now
+vna.cmd(":VNA:ACQ:STOP")
+
+# switch to VNA mode, set up the sweep parameters
+print("Setting up the sweep...")
+vna.cmd(":DEV:MODE VNA")
+vna.cmd(":VNA:SWEEP FREQUENCY")
+vna.cmd(":VNA:STIM:LVL -10")
+vna.cmd(":VNA:ACQ:IFBW 100")
+vna.cmd(":VNA:ACQ:AVG 1")
+vna.cmd(":VNA:ACQ:POINTS 501")
+vna.cmd(":VNA:FREQuency:START 10000000")
+vna.cmd(":VNA:FREQuency:STOP 6000000000")
+
+sweepComplete = False
+
+
+def callback(data):
+    global sweepComplete
+    print(data)
+    if data["pointNum"] == 500:
+        # this was the last point
+        vna.remove_live_callback(19000, callback)
+        sweepComplete = True
+
+
+# Set up the connection for the live data
+vna.add_live_callback(19000, callback)
+print("Starting the sweep...")
+vna.cmd(":VNA:ACQ:RUN")
+
+while not sweepComplete:
+    time.sleep(0.1)
+
+print("Sweep complete")
+
+