Although it's easy to get carried away with using microcontrollers for various tasks, there still lies many tasks for using digital electronics and thus logic ICs. Doing so is educational due to the study of logic gates and their theories, or you may be repairing some older equipment. Either way, the project by Instructables user Zoran1389 will be of interest.
They have demonstrated an Arduino-based logic IC tester that can be used to check TTL ICs by applying the full truth table to the particular IC and displaying the result. In doing so you can test old ICs, and also get a deeper understanding of logic gates. In conjunction with the ICs's data sheet you could modify the sketch for almost any IC and run through all the possible outcomes.
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