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I never had trouble understanding the basic logic tables, but never got around to understand how a combination of gates makes an adder or other computer functio

I never had trouble understanding the basic logic tables, but never got around to understand how a combination of gates makes an adder or other computer functions. Would the visualization extended also make those more clear?

klysm 2y ago
I didn’t get it either until I played the game MHRD. You work from NAND up.
alphazard 2y ago
Lookup "half adder" and "full adder". https://en.wikipedia.org/wiki/Adder_(electronics) https://en.wikipedia.org/wiki/Adder_(electronics)
bazoom42 2y ago
Maybe try https://nandgame.com https://nandgame.com - goes from logic gates to adder to a programmable computer, presented as a series of challenges to solve.
- disambiguation 2y ago
  very similar to this is "Turing Complete" on Steam https://store.steampowered.com/app/1444480/Turing_Complete/ https://store.steampowered.com/app/1444480/Turing_Complete/
aragonite 2y ago
Also see this link for what a simple fluidic adder looks like: http://www.blikstein.com/paulo/projects/project_water.html http://www.blikstein.com/paulo/projects/project_water.html
15155 2y ago
Gate-level addition is happening in binary, it's easier to imagine that way too. https://www.electronics-lab.com/article/binary-adder/ https://www.electronics-lab.com/article/binary-adder/ Define a width of addition operations you'd like to support and work from a 1 bit adder up to that.
bigyikes 2y ago
The trick is binary addition works the same as regular addition, but is so simple that even a silly little logic gate can do it. Think about adding two bits. There are only four possible ways to do it. 0+0=0 0+1=1 1+0=1 1+1=0 (carry 1) If you squint at the bit patterns in those addition facts, you realize it is actually the truth table for XOR (ignoring the carry). So adding bits A and B is the same as taking A XOR B. What about carrying the 1? The carry can be represented as an AND: you only carry the 1 if A and B are both 1. So a simple 1-bit adder can be made by combining an AND and a XOR. Everything becomes simpler when you stop thinking in terms of addition and start thinking in terms of truth tables for bits. Take the truth table for a two bit adder (AB + CD = XY): A B C D X Y 0 0 0 0 0 0 0 0 0 1 0 1 0 0 1 0 0 1 0 0 1 1 1 0 … 1 1 1 1 1 1 If you learn the basic algorithm for converting a truth table into logic gates, you can represent any bit pattern as gates, including addition operations. Adders are nice because you can basically concatenate them together in a chain to add larger and larger patterns of bits.

klysm 2y ago

I didn’t get it either until I played the game MHRD. You work from NAND up.

alphazard 2y ago

Lookup "half adder" and "full adder". https://en.wikipedia.org/wiki/Adder_(electronics) https://en.wikipedia.org/wiki/Adder_(electronics)

bazoom42 2y ago

Maybe try https://nandgame.com https://nandgame.com - goes from logic gates to adder to a programmable computer, presented as a series of challenges to solve.

disambiguation 2y ago
very similar to this is "Turing Complete" on Steam https://store.steampowered.com/app/1444480/Turing_Complete/ https://store.steampowered.com/app/1444480/Turing_Complete/

aragonite 2y ago

Also see this link for what a simple fluidic adder looks like: http://www.blikstein.com/paulo/projects/project_water.html http://www.blikstein.com/paulo/projects/project_water.html

15155 2y ago

Gate-level addition is happening in binary, it's easier to imagine that way too. https://www.electronics-lab.com/article/binary-adder/ https://www.electronics-lab.com/article/binary-adder/ Define a width of addition operations you'd like to support and work from a 1 bit adder up to that.

bigyikes 2y ago

The trick is binary addition works the same as regular addition, but is so simple that even a silly little logic gate can do it. Think about adding two bits. There are only four possible ways to do it. 0+0=0 0+1=1 1+0=1 1+1=0 (carry 1) If you squint at the bit patterns in those addition facts, you realize it is actually the truth table for XOR (ignoring the carry). So adding bits A and B is the same as taking A XOR B. What about carrying the 1? The carry can be represented as an AND: you only carry the 1 if A and B are both 1. So a simple 1-bit adder can be made by combining an AND and a XOR. Everything becomes simpler when you stop thinking in terms of addition and start thinking in terms of truth tables for bits. Take the truth table for a two bit adder (AB + CD = XY): A B C D X Y 0 0 0 0 0 0 0 0 0 1 0 1 0 0 1 0 0 1 0 0 1 1 1 0 … 1 1 1 1 1 1 If you learn the basic algorithm for converting a truth table into logic gates, you can represent any bit pattern as gates, including addition operations. Adders are nice because you can basically concatenate them together in a chain to add larger and larger patterns of bits.