Communication between Arduino and Light Meter

[Bronson_alex]

I just realized that on page 31, it says the RS232 parameter is 9600bps, even parity, 7 bits.
Meaning you cannot use SoftwareSerial, as SoftwareSerial only support None parity, 8 bits.

In that case, you have to use hardware serial and converter.

Serial.begin() - Arduino Reference