Help! I cannot get this to give me any measurement data. I need help with setup. I am connecting this sensor to an Arduino using a Max485 TTL to RS-485 interface module.

I had an issue with range mode 1 (1.5m) only reading once on power up and then reading zero about 10 times before sending the first read value again. Value changed only on power cycle.

Switched to range mode 2 (3m) and got readings every 10 ms as expected.

Here is the python code I got working to read the sensor on windows pc. It initializes to range 2 (3m) and reads every 10 ms. You'll have to update the COM port you use on line 4 manually.


import time
import serial

com_port = 'COM3'

def rec_data(ser):
jl = 0
COM = bytearray([0x50, 0x03, 0x00, 0x34, 0x00, 0x01, 0xC8, 0x45]) #command to read data
ser.write(COM)

if ser.in_waiting >= 7:
data = ser.read(7)
if data[0] == 0x50 and data[1] == 0x03 and data[2] == 0x02 and CRC16_2(data, 5) == (data[5] * 256 + data[6]):
jl = data[3] * 256 + data[4]
return jl

def initialize_range(ser):
range_command = bytearray([0x50, 0x06, 0x00, 0x36, 0x00, 0x02, 0xE5, 0x84]) #command to set range to 3m.
ser.write(range_command)
if ser.in_waiting >= 8:
data = ser.read(8)
time.sleep(0.1)

def CRC16_2(buf, length):
crc = 0xFFFF
for pos in range(length):
crc ^= buf[pos]
for i in range(8, 0, -1):
if crc & 0x0001:
crc >>= 1
crc ^= 0xA001
else:
crc >>= 1
crc = ((crc & 0x00ff) << 8) | ((crc & 0xff00) >> 8)
return crc

if __name__ == "__main__":
try:
ser = serial.Serial(com_port, 115200, timeout=1) #Change to current COM port.
time.sleep(2)
initialize_range(ser)

while True:
distance = rec_data(ser)
print(f"{distance} mm")
time.sleep(0.1)
except serial.SerialException as e:
print(f"Unable to open serial port: {e}")
finally:
if ser.is_open:
ser.close()


Can you provide an sample code for a circuit with Opta finder, or generic for Arduino?
Please help :)

What code did you upload? Please ensure that the voltage is stable. It is recommended to use external power supply