The six counter modules have to be "programmed" according to their position. For example, the counter driving the 10^0 seconds displays always counts to 9 before overflowing. The 10^1 seconds display's counter module always counts to 5 and so... (anybody already wondering?)

The powered up clock looks pretty nice - especially because you can see all the electronics and the fancy LEDs of t he carry chain. The whole clock requires about 95mA at 7V (due to the not-so-efficient 7805).

To configure the time, the clock is paused via the enable switch of the clock. This module also has an reset button to clear all counter. After that, each digit can be increased by hitting the according module's increment button.

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