Identifying a digital logic device from its truth table

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tomizzo
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Homework Statement



On the data sheet, name the device in Figure 9, and appropriately name the four pins A, B, C, and D according to what the device is. Check your Digital Logic book for some guidance.

https://mail.google.com/mail/u/1/?ui=2&ik=ca64811c74&view=att&th=139f410abe33126b&attid=0.1&disp=inline&safe=1&zw

Homework Equations



None

The Attempt at a Solution



So I've set up a truth table for this equation and got

A B C D
0 0 1 1
0 1 1 0
1 0 0 1
1 1 0 0

So having looked at this, it appears as if the two inputs are reversed. However, I'm not sure if there is an actual device out there that this represents, or just a configuration of gates. I've checked my books and nothing sticks out. Any ideas?
 

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At time of writing I can't see the diagram.
 
tomizzo said:

Homework Statement



On the data sheet, name the device in Figure 9, and appropriately name the four pins A, B, C, and D according to what the device is. Check your Digital Logic book for some guidance.

https://mail.google.com/mail/u/1/?ui=2&ik=ca64811c74&view=att&th=139f410abe33126b&attid=0.1&disp=inline&safe=1&zw

Homework Equations



None

The Attempt at a Solution



So I've set up a truth table for this equation and got

A B C D
0 0 1 1
0 1 1 0
1 0 0 1
1 1 0 0

So having looked at this, it appears as if the two inputs are reversed. However, I'm not sure if there is an actual device out there that this represents, or just a configuration of gates. I've checked my books and nothing sticks out. Any ideas?

I'm not able to see the linked image either -- it just takes me to Google g-mail sign-in if I try the link directly...
 
berkeman said:
I'm not able to see the linked image either -- it just takes me to Google g-mail sign-in if I try the link directly...

What link? I don't even see a link in the OP.
 
LCKurtz said:
What link? I don't even see a link in the OP.

Click "Quote" to see the content of his post.

Of course I cheated, and clicked the "Edit" button on his post to see the link, but only green folks have access to that button... :smile:
 
berkeman said:
Click "Quote" to see the content of his post.

Of course I cheated, and clicked the "Edit" button on his post to see the link, but only green folks have access to that button... :smile:

OH NO! This forum is being run by little green men from outer space?
 
berkeman said:
Click "Quote" to see the content of his post.

How does that help? I can see the link but how do we use/edit that to see the image?
 
tomizzo said:
So I've set up a truth table for this equation and got

A B C D
0 0 1 1
0 1 1 0
1 0 0 1
1 1 0 0

So having looked at this, it appears as if the two inputs are reversed. However, I'm not sure if there is an actual device out there that this represents, or just a configuration of gates. I've checked my books and nothing sticks out. Any ideas?
It certainly does appear that C= ¬A and D= ¬B
but until you post your image on a site where it is publicly accessible no one can advise further.
 
CWatters said:
How does that help? I can see the link but how do we use/edit that to see the image?

Sometimes I'm able to paste the link itself into my browser and get to the image, but in this case it didn't work. Other times I can edit the link a bit to get into the website at a higher level and navigate to the image (if it has been moved at the website or something similar).