The electronic clock is simple device showing time in 24 hours system. After changing software and adding temperature probe is also possible to display temperature. To display values was applied super light 7 segments displays 4.0 (101.6mm) with common anode. Clock was built on specialized chip with I2C interface and battery backup. Instead of battery was used high volume capacitor.Controler, which communicated via RS485 interface with each small board which managed 7-segment displays. Every digit display has got an independent impulse supply circuit, what allowed to automatic adjustment of light intensity depend on data from main controller, which measure external light and adjust level of LED lighting. Plexiglas filter excellent guarantee perfect contrast. Setting time is carried out by four buttons remote control. The clock can be install outside, but must be protect against water or snow. There are available other color LED dispalys such as gree, yellow, white, orange or higher displays 5.0'' (125mm).