00:01
All right, so for this question, well, you were to design a combinator, the combination for converting 2 for 2 code to bcd code.
00:16
Okay, so that's really what the question is about.
00:19
I have some things that up here and hopefully it makes sense to you.
00:23
So again, just want to understand the question.
00:27
You're going to go from 24 to 1 code and it's weighted in binary.
00:33
Code binary coded decimal where each bit would have the weights 242 and 1 from left to right and then you have an actual bcd code a standard 4 bit binary representation of this decimal digits you wait 8 to 4 so 8 4 2 1.
00:56
Okay so let us um yeah let's let's let's take a look at what's going on here so couple things that need to be done would be, yeah, you would essentially, well, to construct a combination of logic circuit, right? take 4 -bit inputs and produce 4 -bit output, essentially.
01:33
So this would be the valid.
01:36
This would be some kind of valid.
01:38
This would be not some kind.
01:39
This would be the valid code map.
01:42
And you have that only 10 essentially.
01:46
Only 10 valid 4 -bit inputs exist for 242 -1 coded digit.
01:59
So i want to know that other 4 -bit combinations here are invalid for the decimal digits.
02:09
So we don't have any other thing here.
02:14
So we just want to define the inputs here.
02:16
We're going to have 2421.
02:18
We did the code the input.
02:20
You have the output with the bcd.
02:21
So you have the most significant bit at a and then this is a bit at d for the inputs and you have most everything can bit at w and this if you can bit at the output so yeah this is basically it.
02:37
So here we have the truth table here and this is what would happen you want to go you can design the circuit by going from the trick district table into can all of map and then you have the building expressions other equations equations or you would just write the bullying expressions directly based on the mapping.
02:56
So one way to think about this, right, is to just minimize the bullying expressions for each output using canal for maps.
03:07
All right, so i have an example for you, but to implement the logical circuit, once the expressions are derived, you have to use the a -end or and -k -nodgates.
03:19
You can also use x -nor gate.
03:21
You can connect the input, a -b -c to your logic gates.
03:24
Then you have the outputs wx, y, z as your standard bcc values corresponding to the input 2 -421.
03:33
And so this will be an example here...