CCA ALU

Build image: 
In-game name (NO VISITORS! Must be LEARNER rank or higher!): 
SlidXT
Builder name(s) and current ranks: 
SlidXT, Learner
Creation location: 
1053 154 -297
Machine Features: 
So, this is an Arithmetic Logic Unit, using a Carry Cancel Adder. My CCA, can Add, Subtract and perform bitwise operations, such as (AND, XNAND, OR, XNOR), but of course it can do a couple more. Major components include XOR gates, carry and cancel lines. Basically, simple logic gates and some lines used for adding. The fundamentals is that when you have a carry, it will go on until it finds a bit with a value of 1, In which case, it will go through. Using a glass tower, you will be able to go forward and not backward instantly, which is exactly what we need. Using it, we can have a carry which will help us add. But you may say, what if there is none on? wont the carry still go through even if nothing is on? Well, that's when the cancel line comes into play. It's basically an or gate, where it cancels a comparator, which is what the carry line inputs to, so that if nothing is on, it will cancel, but if either one is on, it will not cancel. Of course, that is not out final output, we need another XOR, between our first XOR's output and our carry output. We must remember to use the previous bit for the output of the carry, since that logic is an AND, where if both inputs are on, it will turn on. The output of our second XOR, is the final result(s). Keep in mind, the CCA is vertical, where the MSB is at the top and LSB at the bottom. Oh yes, about the bitwise. There are inputs around the bottom, which can be on or off. As you can see, they have names such as !A, !B, FC, CIN and OR. Well, I'll explain what each of them do. !A, just inverts the A input, and as you would've guessed, !B inverts the B input. FC, means Flood Carry, which means the carry lines will be active, which usually leads to an inverter. This FC needs CIN to turn on the bottom carry, so keep that in mind. Now CIN, which means Carry In, basically adds 1. For OR, it allows the input to go past the XOR, so it makes the first XOR an OR gate instead. Oh and don't worry about it being 4 bits, you can stack if necessary and move a couple blocks, and then it will work as an 8bit ALU.
How To Use: 
So, after that explanation, which I hope wasn't too long, how do we use this thing? Well, there is a thinner and wider side to the CCA, on the wider side, there are lamps with torches on them. That is where you input your numbers, we have A and B. The left is A and the right is B. Input the numbers with the same format as the output, with the MSB at the top and LSB at the bottom. Around the ALU, specifically at the underside, there are a couple levers there, which correspond to the inputs for the bitwise functions. I've left a table with combinations of inputs to create the desired bitwise or operation which you want. Black means off and White means on. Rows are the resulting operation, and columns the Inputs. Hopefully you can understand my explanation, and the table I've left near to ALU. Also keep in mind, Bitwise does logic for each bit for A and B, for example, if you XOR 1010 and 1110, it'll go 1 XOR 1, 0 XOR 1, 1 XOR 1, 0 XOR 0, you get the idea.
Request status: 
Not approved

Comments

Farex's picture

Hello, SlidXT!

At this time, I have decided to deny your promotion request. It is clear that you understand CCA fairly well and the build itself does not appear to have any issues. However, the main issue is that this build alone does not meet the level of complexity we expect for Regular. If CCA was a new concept you invented, I think it could be a different story, but unfortunately that isn't the case. The build also seems fairly standard in terms of CCA, which isn't necessarily your fault since CCA works quite well this way and that's how it's spread, but it does make it harder to consider this as your own creation.

If this ALU is used to complete challenge number 1 from the in-game "/challenges regular" command, I think it could meet the required logic complexity. With how well you seem to understand CCA and ALUs, I think that challenge would be within your abilities!

Happy redstoning!

Best,
- Farex

By Farex

Oh, I see, I've taken a look at your board here, and an 8bit ICA ALU appears on the list. ICAs, are basically CCAs with pistons instead of comparators and horizontal instead of vertical. My CCA is 4bits rather than 8bits, so if you need 8 bits I would be happy to do so.

By SlidXT

Apologies for the last message, I have now realized that you can skip directly to Regular, as informed by a Builder, so I'll being doing so. I have an 8bit CPU so I will being using so. Also, should I be making another post for that?

By SlidXT

Any ALU alone does not give you a rankup. But yes indeed a CPU does.

However with your CCA you could do the trial!
You will find information in the trial room at spawn and ofc in the /trial command.
It must be an 8 bit CCA ALU with an opcode decoder with at least 8 operations.

The trial will make you Learner+, which also grands you a plot and WorldEdit.

By Ecconia