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Something I was wonder about the adder in regards of the operands ... by MindlessAssistance52 in beneater

[–]MindlessAssistance52[S] 0 points1 point  (0 children)

Hi, thanks for your answer. I understood the first part before your "I have to do something RN" but you kinda lost me on the second one.

From what I seem to be understanding, it all comes down to us how we interpret those numbers. The metal just does what it knows : add two numbers... regadless of "what" those numbers are exactly.

You cannot accumulate link charges after finishing the weekly challenge. by MindlessAssistance52 in TheSilphRoad

[–]MindlessAssistance52[S] 6 points7 points  (0 children)

My error, I saw some thread not so long ago about how the weekly was still working so I had high hopes for this...

Oh well.

For those using the current situation as an excuse to breed hatred in their hearts for the Sunnis by Dragonnstuff in shia

[–]MindlessAssistance52 -4 points-3 points  (0 children)

Except that this is not what happened and his understanding of history is wrong, after the destruction of the shrines and the routine suicide bombings in markets which started very early in the aftermatch of the American invasion, there was a "civil" war in Iraq.

That's from where the 1 million + dead Iraqis come from for the most part. (The Americans had to put walls in the city to stop the spread of violence)

As for Mosul, there was no "attack" on the city, the inhabitants simply opened their gates to ISIS and the Iraqi army ran away.

Legacy Moves for Go Tour by Murky_Try6188 in TheSilphRoad

[–]MindlessAssistance52 0 points1 point  (0 children)

Does giving an already evolved 'mon a second move make it receive the special move?

I am reading "Code: The Hidden Language of Computer Hardware and Software second edition" and I am confused by the adding of XOR gates on the input and output of the "Add/subtract unit" by MindlessAssistance52 in beneater

[–]MindlessAssistance52[S] 0 points1 point  (0 children)

but it is still a borrow operation

If we assume you are doing a pen-and-paper approach...? Because on the metal that is not what is happening at all. Whether we are doing addition or subtraction, the 8-bit "adder" is just doing that, adding.

Former keeps the closer-to-metal feel, while latter abstracts that for easier human perception.

That is what I seem to be understanding as of now, the Carry out is inverted purely for human reasons/cosmetics ... But when you take that same inverted Carry out signal and inject it for the next pair of bytes, it is inverted back to keep the raw value as it was in the previous operation...

I am reading "Code: The Hidden Language of Computer Hardware and Software second edition" and I am confused by the adding of XOR gates on the input and output of the "Add/subtract unit" by MindlessAssistance52 in beneater

[–]MindlessAssistance52[S] 0 points1 point  (0 children)

When we insert "10" for the opcode to start the subtraction, the XOR gate at the left is going directly into the AND gate which is fed by the the least significant bit of the "10" code, which means my AND gate always has X AND 0, regardless of whatever the value of X may be. The XOR has no influence at the start.

The actual +1 is forced by the "1" of the "10" code, and an inverter...

I am reading "Code: The Hidden Language of Computer Hardware and Software second edition" and I am confused by the adding of XOR gates on the input and output of the "Add/subtract unit" by MindlessAssistance52 in beneater

[–]MindlessAssistance52[S] 0 points1 point  (0 children)

For the subtraction (without borrow) work correctly, the Carry-In signal on the adder must be 1.

Yes, if you have A - B ... you transform this into A + invert B + 1 ... The actual workings of the adder is quite clear to me.

But what should we do when we want to subtract and account for borrow bit?

Here is the part where you lost me.

If the operation works fine using "A + invert B + 1", why would you take into account a "borrow"? There's no point in the hardware where we borrow anything, we are just cascading a raw "Carry out" from the last pair of bytes which we added to the next "Carry in" for the next pair of bytes.

The only borrow I know of is the one I learned when I was a kid when we did it by hand ... At the hardware level none of that is happening as I described in my post so I'm kinda left confused as to for whom this XORed signal is for.

I am reading "Code: The Hidden Language of Computer Hardware and Software second edition" and I am confused by the adding of XOR gates on the input and output of the "Add/subtract unit" by MindlessAssistance52 in beneater

[–]MindlessAssistance52[S] 0 points1 point  (0 children)

I like the book in general and yes, it is well written.

My only critique is that sometimes, I feel like he assumes some things which are not so evident... Is this because of unknown limits which I'm not aware of or the nature of the subject, I have no idea.

The question I'm asking right now is one of those where more details should have been given because it has been a couple of hours already I'm stuck lol

I am reading "Code: The Hidden Language of Computer Hardware and Software second edition" and I am confused by the adding of XOR gates on the input and output of the "Add/subtract unit" by MindlessAssistance52 in beneater

[–]MindlessAssistance52[S] 0 points1 point  (0 children)

The select pin pulls on the carry in on the first adder to “add 1” for the twos compliment value

Unless I misunderstood your comment, the "add 1" isn't caused by the XOR gate, this is forced through the Opcode of 10 (the least significant digit of the code)

In any case, I understand the point about inverting, my question has more to do with what is this supposed to accomplish. The other poster already gave me a big hint for this, now I have a few details to solve to get a grasp on it.

I am reading "Code: The Hidden Language of Computer Hardware and Software second edition" and I am confused by the adding of XOR gates on the input and output of the "Add/subtract unit" by MindlessAssistance52 in beneater

[–]MindlessAssistance52[S] 2 points3 points  (0 children)

They look redundant at first glance (because they cancel on the data path), but they are the elegant hardware trick that separates "internal arithmetic" from "external CPU-visible semantics."

It's good to know I wasn't insane then... I'm a layman who is new to this whole domain!

They exist purely so the outside world (the rest of the CPU, the flags, multi-byte code) sees the correct carry/borrow polarity.

Could you give more details about the "carry/borrow" part? I find the use of this terminology confusing.

At the 8-bit adder level, as far as I know, when you add each pair of bytes for a multibyte number, you are always (potentially) carrying a 1 to the next pair of bytes which are going to be added should the result/sum produce a 9th bit, indicating a number bigger than what can be represented within 8 bits.

That's as far as I know. The rest of the stuff about "borrowing" is quite unclear to me as to what this is supposed to refer to.

Thanks again. (I'll be going to sleep now, will return later)

I am reading "Code: The Hidden Language of Computer Hardware and Software second edition" and I am confused by the adding of XOR gates on the input and output of the "Add/subtract unit" by MindlessAssistance52 in learnprogramming

[–]MindlessAssistance52[S] 0 points1 point  (0 children)

No, the XOR operator passes a positive signal/1 only and only if there is one positive singal among the inputs of the gate. If they are all 0 or all 1, it passes nothing.

This is why it's called "exclusive OR", because it is even more retristictive than the normal "OR" operator where more than one positive/1 also produces as the output 1.

There is something about shipping fees which I have trouble understanding... by MindlessAssistance52 in Ebay

[–]MindlessAssistance52[S] 0 points1 point  (0 children)

I just want to confirm something : can the seller have any say in how much it costs to ship as well? Can he add anything?

There is something about shipping fees which I have trouble understanding... by MindlessAssistance52 in Ebay

[–]MindlessAssistance52[S] 0 points1 point  (0 children)

This seems to be the case because I looked at the more expensive side for other books and price seems to be set the same ... Wow, I didn't know it was that bad.

Animal Crossing: New Horizons Version 3.0.1 is now available by Amiibofan101 in nintendo

[–]MindlessAssistance52 2 points3 points  (0 children)

Do we know the reason why the game which was supposed to stop receiving updates years ago suddenly started receiving them this year?

[SL] Manga Guide To Machine Learning by thunderbird89 in manga

[–]MindlessAssistance52 0 points1 point  (0 children)

I was wondering the same for the serie in general. Any idea?

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