commit 52c6c2b2e8cfe2fccf6c1c2034454550de654513
Author: Kai Vogelgesang <kai@leafbla.de>
Date:   Tue Jul 1 16:51:58 2025 +0200

    Init

diff --git a/ultrasound/.gitignore b/ultrasound/.gitignore
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index 0000000..7c0bf87
--- /dev/null
+++ b/ultrasound/.gitignore
@@ -0,0 +1,2 @@
+.venv
+typings
diff --git a/ultrasound/Makefile b/ultrasound/Makefile
new file mode 100644
index 0000000..24842cd
--- /dev/null
+++ b/ultrasound/Makefile
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+.PHONY: deploy
+deploy:
+	mpremote fs cp src/* :
+
+.PHONY: run
+run: deploy
+	mpremote exec "import main; main.main()"
diff --git a/ultrasound/README.md b/ultrasound/README.md
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index 0000000..08eba16
--- /dev/null
+++ b/ultrasound/README.md
@@ -0,0 +1,6 @@
+# Setup:
+```
+$ python -m venv .venv
+$ source .venv/bin/activate
+$ pip install -U micropython-rp2-pico_w-stubs --no-user --target typings
+```
diff --git a/ultrasound/pyproject.toml b/ultrasound/pyproject.toml
new file mode 100644
index 0000000..65df247
--- /dev/null
+++ b/ultrasound/pyproject.toml
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+[tool.basedpyright]
+reportMissingModuleSource=false
+reportUnusedCallResult=false
+reportUnknownMemberType=false
+
+stubPath = "typings"
+typeshedPath = "typings"
\ No newline at end of file
diff --git a/ultrasound/src/main.py b/ultrasound/src/main.py
new file mode 100644
index 0000000..595895d
--- /dev/null
+++ b/ultrasound/src/main.py
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+from machine import Pin
+import machine
+import time
+import asyncio
+
+class StatusLED:
+    led: Pin
+    _status: int
+    _period: float
+    _duty_cycle: float
+
+    def __init__(self):
+        self.led = Pin("LED", Pin.OUT)
+        self._status = 1
+        self._period = 1
+        self._duty_cycle = 0.5
+
+    def status(self, status: int):
+        self._status = status
+        
+    
+    async def task(self):
+        while True:
+            t_1 = self._duty_cycle * self._period
+            t_2 = (1 - self._duty_cycle) * self._period
+
+            t_blink = t_1 / self._status / 2
+            for _ in range(self._status):
+                self.led.value(1)
+                await asyncio.sleep(t_blink)
+                self.led.value(0)
+                await asyncio.sleep(t_blink)
+            
+            await asyncio.sleep(t_2)
+
+STATUS_LED = StatusLED()
+
+
+class UltraSonicSensor:
+    """
+    See https://randomnerdtutorials.com/micropython-hc-sr04-ultrasonic-esp32-esp8266/
+    """
+
+    tx: Pin
+    rx: Pin
+
+    def __init__(self, tx: int, rx: int):
+        self.tx = Pin(tx, Pin.OUT)
+        self.rx = Pin(rx, Pin.IN)
+        
+    def query_mm(self):
+        self.tx.value(0)
+        time.sleep_us(5)
+        self.tx.value(1)
+        time.sleep_us(10)
+        self.tx.value(0)
+        
+        pulse_time = machine.time_pulse_us(self.rx, 1, 500*2*30)
+        if pulse_time < 0:
+            return None
+        
+        return pulse_time * 100 // 582
+    
+
+
+async def _main():
+    asyncio.create_task(STATUS_LED.task())
+    sensor = UltraSonicSensor(22, 21)
+    while True:
+        d = sensor.query_mm()
+        print(f"d: {d} mm")
+        await asyncio.sleep(0.5)
+
+def main():
+    asyncio.run(_main())
+
+
+if __name__ == "__main__":
+    main()