This application note describes how to directly read and write data directly to the SenseAir K30 and K33 line of CO2 sensors.
Please read the MODBUS specification document before reading this document to gain a background understanding on the sensor’s implementation of MODBUS and for checksum calculating algorithms. Using these commands opens up the entire EEPROM and RAM of the sensor for UART access. It will also allow us to access the sensor using the memory locations described in the I2C guide.