Goal: to show digits on seven segment indicator.

What we have: pic16f628a and 7-segment indicator with common cathode, shift register 74hc164.

From the start – I’ve used shift register because it’s very wasteful to use 8 pins of uc for one 7-segment indicator. With this shift register we can use only 4 pins:

1. For clock
2. For reset.
3. For data.
4. For supply transistor.

There is no description of the shift register work, just about 7-segment indicator.

So, for the begining, let’s build simple test setup and write code, which will display all digits with 1s period (like a stopwatch:)).

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