I've been building a circuit with a 4bit adder and was getting some strange results that I couldn't explain. It appears that 1 + 3 = 8. See picture below. Is that right or am I reading something wrong?
S3 is high and represents the four bit which represents 8 correct? This happens two more times for addition where A0 and A1 are both high. 1 + 7 = 12 and 1 + 11 = 4.
Please explain what I might be doing wrong or maybe a bug.
Thanks for helping out!
I got it figure out. The data sheet was incorrect in the simulator. Once I swapped s2 <--> s3 everything is working great.
First picture is the Crumb schematic and the second I found online. I used the second one for the correct wiring.
It is kind of a bug fix after all.
Hope this helps someone else.