Merge pull request #201 from sandialabs/list-resources-feat

List resources feat

Author: rsbrost

pyscan/general/get_resources.py

@@ -0,0 +1,53 @@
+from pyvisa import ResourceManager, VisaIOError
+
+
+def get_resources(print_resources=True):
+    """
+    Returns a list of connected VISA GPIB addresses and optionally (by default)
+    tries to print them paired with their corresponding ID strings.
+
+    This function uses the PyVISA library to return a list of all resources (instruments) available to the system.
+    It tries to connect to each instrument and prints the error message if unable to.
+    If `list_resources` is set to True, it attempts to query and print the IDs of each instrument.
+
+    Parameters
+    ----------
+    list_resources : bool
+        If True (default), queries and prints instrument connection addresses paired with their ID strings if available.
+        If False, only returns the available resources without querying their IDs.
+
+    Returns
+    -------
+    resources_listed : tuple
+        A list of resource connections (strings) representing the instruments detected by the system.
+    """
+    rm = ResourceManager()
+    resources_listed = rm.list_resources()
+    resource_dict = {}
+
+    for r in resources_listed:
+        try:
+            # Connect to the instrument
+            res = rm.open_resource(r)
+        except VisaIOError as e:
+            print(f"{e}\n Could not connect to instrument {r}, may already be connected elsewhere.")
+            continue
+
+        try:
+            # Try to query the I.D. of the instrument
+            name = res.query('*IDN?')
+            resource_dict[r] = name
+
+            # If found and print resources is true, print the resource as well as the I.D.
+            if print_resources is True:
+                print(r, name)
+        except VisaIOError:
+            resource_dict[r] = "Instrument I.D. could not be queried."
+            if print_resources is True:
+                print(r, "Instrument I.D. could not be queried.")
+
+        # We are no longer closing the connection by defualt since this could close connections that were open before
+        # and there is no way of telling if a connection was already open automatically.
+        # res.close()
+
+    return resource_dict