Make laser flashes more responsive

firmware/hardware.py

@@ -1,3 +1,5 @@
+import asyncio
+
 import async_button
 import async_buzzer
 
@@ -26,6 +28,9 @@ class HardwareBase:
     bt: bluetooth.BluetoothServices
     batt_voltage: float
 
+    def __init__(self):
+        self.laser_task: Optional[asyncio.Task] = None
+
     def __enter__(self):
         return self
 
@@ -41,11 +46,24 @@ def laser_enable(self, value):
         pass
 
     @abstractmethod
-    def laser_on(self, value):
+    async def laser_on(self, value):
         pass
 
+    def flash_laser(self, count: int, speed: float):
+        if self.laser_task:
+            if not self.laser_task.done():
+                self.laser_task.cancel()
+        self.laser_task = asyncio.create_task(self._flash_laser(count, speed))
+
+    async def _flash_laser(self, count: int, speed: float):
+        for _ in range(count):
+            await self.laser_on(False)
+            await asyncio.sleep(speed)
+            await self.laser_on(True)
+            await asyncio.sleep(speed)
+
     @abstractmethod
-    def laser_measure(self):
+    async def laser_measure(self):
         pass
 
     @abstractmethod

firmware/measure.py

@@ -106,7 +106,6 @@ async def get_raw_measurement(devices: hardware.HardwareBase, disp: display.Disp
         logger.debug(f"Mag: {mag}")
         grav = devices.accelerometer.acceleration
         logger.debug(f"Grav: {grav}")
-        await asyncio.sleep(0.1)
         await devices.laser_on(True)
     finally:
         disp.sleep(wake=True)
@@ -135,26 +134,20 @@ async def take_reading(devices: hardware.HardwareBase,
         logger.info(f"Measurement error: {repr(exc)}")
         if not isinstance(exc, asyncio.TimeoutError):
             # don't wibble the laser if it's timed out, it'll just get more confused
-            for i in range(5):
-                await devices.laser_on(False)
-                await asyncio.sleep(0.1)
-                await devices.laser_on(True)
-                await asyncio.sleep(0.1)
+            devices.flash_laser(5,0.1)
         devices.beep_sad()
+        await asyncio.sleep(0)
         return False
     else:
         leg = Leg(azimuth, inclination, distance)
         readings.store_reading(leg, cfg)
         devices.bt.disto.send_data(azimuth, inclination, distance)
         if readings.triple_shot():
-            for _ in range(2):
-                await devices.laser_on(False)
-                await asyncio.sleep(0.2)
-                await devices.laser_on(True)
-                await asyncio.sleep(0.2)
+            devices.flash_laser(2,0.2)
             devices.beep_happy()
         else:
             devices.beep_bip()
+        await asyncio.sleep(0)
         return True
 
 

firmware/versions/hardware_v1.py

@@ -1,3 +1,4 @@
+import asyncio
 import time
 
 import async_button
@@ -21,6 +22,7 @@
 class Hardware(HardwareBase):
     def __init__(self, pins):
         logger.debug("Initialising hardware")
+        super().__init__()
         import displayio
         displayio.release_displays()
         self._las_en_pin = digitalio.DigitalInOut(pins.LASER_EN)
@@ -36,7 +38,7 @@ def __init__(self, pins):
         self._drdy_io.direction = digitalio.Direction.INPUT
         # noinspection PyTypeChecker
         self.magnetometer = rm3100.RM3100_I2C(self._i2c, drdy_pin=self._drdy_io, cycle_count=2000)
-        self._uart = busio.UART(pins.TX, pins.RX, baudrate=9600)
+        self._uart = busio.UART(pins.TX, pins.RX, baudrate=9600, timeout=0.1)
         self._uart.reset_input_buffer()
         self._laser = laser_egismos.AsyncLaser(self._uart)
         if pins.BUZZER_B is None:
@@ -73,9 +75,18 @@ def laser_enable(self, value: bool) -> None:
         self._las_en_pin.value = value
 
     async def laser_on(self, value: bool) -> None:
+        await self._laser_mutex()
         await self._laser.set_laser(value)
 
+    async def _laser_mutex(self):
+        """This function waits for the laser task to complete before proceeding"""
+        if self.laser_task and not self.laser_task.done():
+            if asyncio.current_task() is not self.laser_task:
+                #don't wait if we're actually *in* the laser task
+                await self.laser_task
+
     async def laser_measure(self) -> float:
+        await self._laser_mutex()
         self._laser.async_reader.s.read()  # clear the buffer
         return await self._laser.measure()