Pure digital circuit clock

Small bug: When running normally, the hours and minutes may be accidentally triggered. It may be that the button filtering affects the original signal.....
Small bug: After the seconds and minutes are greater than 50, the buttons cannot be used to adjust them. The time of the first level, such as when the seconds is 50-59, the minutes cannot be adjusted by pressing the button, because the clear signal of the previous level is always at a low level (it needs to be at a high level to adjust the time normally (i.e. The seconds are between 0-49)), and the buttons cannot be adjusted. You need to wait until the low level of the previous level ends before you can adjust it.
waiting for update. . .
 
Attachment description: NumberTime0403 is a PCB proofing file
multisim 14 that contains decimal, 24-digit, and 60-digit counter files. Note: CD4511 was not found in multisim 14, so the common anode digital tube driven by 74LS47 was used. However, the circuit uses a common cathode digital tube driven by CD4511, and the principle is the same. No matter which one is used, the effect is the same, but attention should be paid to the selection of digital tubes.