Asynchronous Python serial interface to HLDS lidar. After instantiating a LIDAR object, start() the lidar and await a call to getLidar() to obtain coordinates and intensities of lidar points.
async def runLIDAR():
lidar = LIDAR()
lidar.start()
lidarXY = await lidar.getLIDAR()
x, y, intensities = lidarXY
# ...
lidar.stop()
asyncio.run(runLIDAR())
Where Rx and Tx are 3.3V serial receive and transmit lines. For example, connect these to the UART Tx and Rx pins on a Raspberry Pi (pins 8 and 10). Be aware however that most Arduinos use 5V signalling, so in this case you would need to use a level shifter. The baud rate of the HLDS LIDAR is 230400.
By default the LIDAR interface class is designed for use with a Raspberry Pi, where the default serial interface is on port /dev/ttyAMA0.
When activated, the LIDAR interface sends a b character to turn the LIDAR device on. When getLidar() is called asynchronously, the interface waits until the start of a data frame is captured, reads out the entire frame (this might take a couple of seconds), and then returns it using asyncio. If the interface object is deleted (for example, if it gets garbage collected or the program terminates), an e character is sent to turn the LIDAR device off cleanly.
