Add persistent parameter example

Author: gemenerik

examples/persistent_param.py

@@ -0,0 +1,142 @@
+# ,---------,       ____  _ __
+# |  ,-^-,  |      / __ )(_) /_______________ _____  ___
+# | (  O  ) |     / __  / / __/ ___/ ___/ __ `/_  / / _ \
+# | / ,--'  |    / /_/ / / /_/ /__/ /  / /_/ / / /_/  __/
+#    +------`   /_____/_/\__/\___/_/   \__,_/ /___/\___/
+#
+# Copyright (C) 2025 Bitcraze AB
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program. If not, see <http://www.gnu.org/licenses/>.
+"""
+Demonstrate persistent parameter storage on the Crazyflie.
+
+Persistent parameters retain their values across reboots by storing them
+in EEPROM. This example shows how to:
+- List all persistent parameters
+- Get default values
+- Query persistent storage state
+- Store a parameter value to EEPROM
+- Clear a stored value from EEPROM
+
+Example usage:
+    python persistent_param.py                                    # Use default URI
+    python persistent_param.py --uri radio://0/80/2M/E7E7E7E701  # Custom URI
+"""
+
+import asyncio
+from dataclasses import dataclass
+
+import tyro
+
+from cflib2 import Crazyflie, LinkContext
+
+
+@dataclass
+class Args:
+    uri: str = "radio://0/80/2M/E7E7E7E7E7"
+    """Crazyflie URI"""
+
+
+async def main() -> None:
+    args = tyro.cli(Args)
+
+    print(f"Connecting to {args.uri}...")
+    context = LinkContext()
+    cf = await Crazyflie.connect_from_uri(context, args.uri)
+    print("Connected!\n")
+
+    param = cf.param()
+
+    try:
+        # Step 1: List persistent parameters
+        print("=== Persistent Parameters ===")
+        persistent_params = []
+
+        for name in param.names():
+            if await param.is_persistent(name):
+                persistent_params.append(name)
+
+        print(f"Found {len(persistent_params)} persistent parameters\n")
+
+        # Step 2: Get default values
+        print("=== Default Values ===\n")
+
+        test_params = ["ring.effect", "activeMarker.back", "pm.lowVoltage"]
+
+        for name in test_params:
+            value = await param.get_default_value(name)
+            print(f"{name}: {value}")
+
+        # Step 3: Get persistent state
+        print("\n=== Persistent Parameter States ===\n")
+
+        for name in test_params:
+            state = await param.persistent_get_state(name)
+            print(f"{name}:")
+            print(f"  Default value: {state.default_value}")
+            if state.is_stored:
+                print(f"  Stored value:  {state.stored_value}")
+            else:
+                print("  Stored: No (using default)")
+            print()
+
+        # Step 4: Store a value to EEPROM
+        print("=== Storing a Parameter ===\n")
+
+        test_param = "ring.effect"
+
+        current_value = await param.get(test_param)
+        print(f"Current value of {test_param}: {current_value}")
+
+        new_value = 10
+        print(f"Setting {test_param} to {new_value}")
+        await param.set(test_param, new_value)
+
+        print("Storing to EEPROM...")
+        await param.persistent_store(test_param)
+        print("Stored successfully!\n")
+
+        # Verify it's now marked as stored
+        state = await param.persistent_get_state(test_param)
+        print("Verification:")
+        print(f"  Default value: {state.default_value}")
+        if state.is_stored:
+            print(f"  Stored value:  {state.stored_value}")
+        else:
+            print("  Stored: No (using default)")
+
+        # Step 5: Clear a stored value from EEPROM
+        print("\n=== Clearing a Stored Parameter ===\n")
+
+        print("Clearing stored value from EEPROM...")
+        await param.persistent_clear(test_param)
+        print("Cleared successfully!\n")
+
+        # Verify it's now using the default again
+        state = await param.persistent_get_state(test_param)
+        print("Verification:")
+        print(f"  Default value: {state.default_value}")
+        if state.is_stored:
+            print(f"  Stored value:  {state.stored_value}")
+        else:
+            print("  Stored: No (using default)")
+
+    finally:
+        print("\nDisconnecting...")
+        await cf.disconnect()
+        print("Done!")
+
+
+if __name__ == "__main__":
+    asyncio.run(main())