用于超声波传感器HC-SR04 的 Micropython 驱动程序_Python_代码_相关文件_下载

# HC-SR04 Sensor driver in micropython Micropython driver for the well-known untrasonic sensor [HC-SR04](https://www.mpja.com/download/hc-sr04_ultrasonic_module_user_guidejohn.pdf) The driver has been tested on Wemos D1 mini PRO, but It should work on whatever other micropython board, if anyone find problems in other boards, please open an issue and we'll see. ## Motivation The existing drivers in micropython are a bit old and they don't use the relatively new method `machine.time_pulse_us()` which Is more accurate that whatever other method using pure python, besides the code is compliant with "standard" micropython, there is no code for specific boards. Finally I've added a method, `distance_mm()` that don't use floating point operations, for environments where there is no floating point capabilities. ## Examples of use: ### How to get the distance The `distance_cm()` method returns a `float` with the distance measured by the sensor. ```python from hcsr04 import HCSR04 sensor = HCSR04(trigger_pin=16, echo_pin=0) distance = sensor.distance_cm() print('Distance:', distance, 'cm') ``` There is another method, `distance_mm()`, that returns the distance in milimeters (`int` type) and **no floating point is used**, designed for environments that doesn't support floating point operations. ```python distance = sensor.distance_mm() print('Distance:', distance, 'mm') ``` The default timeout is based on the sensor limit (4m), but we can also define a different timeout, passing the new value in microseconds to the constructor. ```python from hcsr04 import HCSR04 sensor = HCSR04(trigger_pin=16, echo_pin=0, echo_timeout_us=1000000) distance = sensor.distance_cm() print('Distance:', distance, 'cm') ``` ### Error management When the driver reaches the timeout while is listening the echo pin the error is converted to `OSError('Out of range')` ```python from hcsr04 import HCSR04 sensor = HCSR04(trigger_pin=16, echo_pin=0, echo_timeout_us=10000) try: distance = sensor.distance_cm() print('Distance:', distance, 'cm') except OSError as ex: print('ERROR getting distance:', ex) ```