diff --git a/ner_environment/build_system/build_system.py b/ner_environment/build_system/build_system.py
index 94cd7df..6ffc695 100644
--- a/ner_environment/build_system/build_system.py
+++ b/ner_environment/build_system/build_system.py
@@ -163,17 +163,12 @@ def flash(ftdi: bool = typer.Option(False, "--ftdi", help="Set this flag if the
 
 @app.command(help="Open UART terminal of conneced device")
 def serial(list: bool = typer.Option(False, "--list", help="Specify the device to connect or disconnect (e.g., /dev/ttyACM0,/dev/ttyUSB0,/dev/ttyUSB1,COM1)"),
-           device: str = typer.Option(None, "--device", "-d", help="Specify the board to connect to")):
-
-    if device:
-        dev = device
-    else:
-        dev = None
+           device: str = typer.Option("", "--device", "-d", help="Specify the board to connect to")):
 
     if list:
-        miniterm(list=True, device=dev)
+        miniterm(list=True, device=device)
     else:
-        miniterm(list=False, device=dev)
+        miniterm(device=device)
 
 # ==============================================================================
 # Update command
diff --git a/ner_environment/build_system/miniterm.py b/ner_environment/build_system/miniterm.py
index de614e7..d8204bd 100644
--- a/ner_environment/build_system/miniterm.py
+++ b/ner_environment/build_system/miniterm.py
@@ -42,9 +42,9 @@ def run_miniterm(device, baudrate=115200):
         print(f"Failed to run pyserial-miniterm: {e}", file=sys.stderr)
         sys.exit(1)
 
-def main(list=False, device=None):
+def main(list=False, device=""):
     # Detect the operating system and find USB devices
-    if not device:
+    if device == "":
         # reverse so FTDI is the default if present, can always be overridden
         devices = list(reversed(list_usb_devices()))