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Altera_Forum
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15 years ago

VHDL HC237 3-8 Decoder with latches

Hello, I'm trying to write the VHDL code for chip HC237. I think I have something written that will work for the most part, but my problem is in dealing with pin GL. Basically what this chip does i...
Altera_Forum's avatar
Altera_Forum
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15 years ago

I would not try and build transparant latches - you will run into all sorts of problems as you cannot garante timing with them. You would also be creating latches for Y because it is not given a value when GL = '0'. And if A,B,C are meant to be the bits from I, you cannot drive an input port.

I would first bring a clock into the design, it will make your life much much easier.