Electronic lock for 8 digits

Electronic lock for 8 digits. In the archives, there are 2 schemes that differ in the way of comparing the secret code and the code entered from the keyboard. There are more than 4 billion possible combinations.

Very good project Fizik_S 
Sorry I pushed it from the front page with my opamp-examples, this post will push it back   
I want to ask you, in which version is this made so I will know in which folder to place the download?
Thanks

This project was created in SimulIDE 0.4.15. SR1

I cracked your HC688 code 



Didn't notice that the led only stays on as long as you keep the enter button pressed so you had me going for an hour. Very nice project, didn't go into all the details of every chip yet but it is very well made if I may say so.

MM74C922-16 bit encoder
nice

You draw very thight to make it fit, not wasting one millimeter and even crossing over other pins 
Did you copy some of your tunnels? If so than it's working good, since my Ben Eater bread board project I avoided it. Would like to try it again because it saves a lot of time.

Did you copy some of your tunnels?

I copy elements enough when designing schemas. This saves a lot of time. If there are errors in the program, then I do not use the function that causes the error. Errors are quickly corrected and the new version of the program does not contain them (as a rule). Therefore, I am calm about errors in the program. You need to make it a rule to periodically run the simulation of the circuit. I.e. debug the circuit in parts. This rule will allow you to develop the device much faster and more efficiently. It is easier to look for errors in individual blocks than in the whole scheme. You can make each block as a separate circuit, debug it, and then connect them into a single circuit.

A lot of changes have been made in the Simulate 1.0.1 program, as a result, some schemes, including this one, have stopped being correctly simulated. The attachment contains a corrected scheme that works correctly in new versions of the program.