capacitor c 1 discharged the pin gp 1 is turned to be an input end with a high impedance to detect the solar cells through a resistor r 1 then the microprocessor shall go judging whether it is now in daytime or not by detecting the charging state of the capacitor c 1 if positive c 1 is charged gradually otherwise the microprocessor should prepare to flash by the way an auxiliary ic mcp809 of microchip is also provided to inspect the power voltage to keep the microprocessor working smoothly a second pin gnd of the ir receiver tsop18x of vishay is connected with pin gp 2 of the microprocessor in the duration between two flashes the microprocessor would enter a sleep mode to consume current in 2 u03bca only to lower down the power consumption and the receiver might be shut down then and there and reopened at the moment the microprocessor is supposed to receive a flash trigger signal so that more power consumption can be saved also in the microprocessor pin gp 5 outputs low to lighten an led d 3 while gp 4 outputs low to lighten an ir led d 2 the related flash parameters are stored in the eeprom of the microprocessor the operating highlights are summarized as the following 1 a flash period may be set at 0 5 seconds for example the microprocessor is requested to flash repeatedly by this period on it 39 s own before a flash control signal is detected and received 2 a detection time for detecting a flash control.