features/unit/ultrasonic: I2C interface ultrasonic distance sensor

Author: pandiannano

m5stack/libs/unit/ultrasonic_i2c.py

@@ -0,0 +1,34 @@
+from machine import I2C
+from .pahub import PAHUB
+from .unit_helper import UnitError
+import time
+
+try:
+    from typing import Union
+except ImportError:
+    pass
+
+class ULTRASONIC_I2C:
+
+    def __init__(self, i2c: Union[I2C, PAHUB], addr=0x57):
+        self.i2c = i2c
+        self.i2c_addr = addr
+        self._distance = 0
+        self._available()
+
+    def _available(self):
+        if not (self.i2c_addr in self.i2c.scan()):
+            raise UnitError("Ultrasonic unit maybe not connect")
+
+    def get_target_distance(self, mode=1):
+        try:
+            self.i2c.writeto(self.i2c_addr, bytearray([0x01]))
+            time.sleep_ms(150)
+            data = self.i2c.readfrom(self.i2c_addr, 3)
+            self._distance = ((data[0] << 16) | (data[1] << 8) | data[2]) / 1000
+        except OSError:
+            pass
+        if mode == 2:
+            self._distance = self._distance / 10 
+        return round(self._distance, 2)
+