Hello everyone.
We have a 3rd semester project to do.
It goes something like this:
Design a parking lot with 12 spots. When a car enters, the counter must count up and when one leaves, it must count down. Also, if the lot is at it's limit, the entry gate should remain closed even if a car approaches.
I have completed most of what the project asks for(with some help from the internet and my friends)-my Proteus ISIS schematic counts up and down. However our instructor brought to our attention the fact that when the lot is at it's limit, and another car approaches the gate, it must not make the counter count up from 12. She also said that it shouldn't count down from 00 i.e it shouldn't go from 00 to 99 (although practically there isn't much chance of that happening).
What do you guys think I should do? Is there some way I can wire the U/D of both 74ls190s so that they do not count up when the counter reaches 12 but they DO count down...?
I know that the E-pin stops the counting, but it stops it altogether. D: I need it to still count down at 12!!
Thanks in advance
We have a 3rd semester project to do.
It goes something like this:
Design a parking lot with 12 spots. When a car enters, the counter must count up and when one leaves, it must count down. Also, if the lot is at it's limit, the entry gate should remain closed even if a car approaches.
I have completed most of what the project asks for(with some help from the internet and my friends)-my Proteus ISIS schematic counts up and down. However our instructor brought to our attention the fact that when the lot is at it's limit, and another car approaches the gate, it must not make the counter count up from 12. She also said that it shouldn't count down from 00 i.e it shouldn't go from 00 to 99 (although practically there isn't much chance of that happening).
What do you guys think I should do? Is there some way I can wire the U/D of both 74ls190s so that they do not count up when the counter reaches 12 but they DO count down...?
I know that the E-pin stops the counting, but it stops it altogether. D: I need it to still count down at 12!!
Thanks in advance
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