A design of low cost illuminometer with multiple functions

This paper designed a novel illuminometer with low price and multiple functions compared with most commercial illuminometer. In addition to illumination measurement, the meter can also measure temperature and humidity used for measuring its working environment, even conduct wireless communication each other. The meter circuit design was provided, such as interface of light sensor to microcontroller respectively. A data Tx/Rx method of communication unit using its nIRQ pin was presented, which do Tx/Rx according to content of status register in interrupt service routine. Program flow char of driving digitrons to do dynamic display was presented. Finally, measurement result comparison was done with two commercial illumination meter.