Hello
Just joined the forum and I'm a novice so, apologies if my question is a bit daft.
Trying to make a 4 bit adder, but as soon as I tested a simple chip with AND gates (tested 3 in case 1st was faulty) it doesn't seem to make sense.
Dip switches: A : ON B :OFF (A and B should be OFF) and LED is ON.
LED is only off if both A+B are off
(photo for reference in case I messed up connecting anything)
Many thanks in advance
Miguel
CHIP CD4081BE
PS - on that first XOR gates chip I don't even need to connect A or B if A+B output goes to LED, it lights up. (very frustrating)
Just joined the forum and I'm a novice so, apologies if my question is a bit daft.
Trying to make a 4 bit adder, but as soon as I tested a simple chip with AND gates (tested 3 in case 1st was faulty) it doesn't seem to make sense.
Dip switches: A : ON B :OFF (A and B should be OFF) and LED is ON.
LED is only off if both A+B are off
(photo for reference in case I messed up connecting anything)
Many thanks in advance
Miguel
CHIP CD4081BE
PS - on that first XOR gates chip I don't even need to connect A or B if A+B output goes to LED, it lights up. (very frustrating)
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