Truth Table

Here’s another post about the new electrics. This time it is a funky little device called Truth Table Circuit.

Truth Table Circuit

Truth Table Circuit. Four inputs. The output is at the back.

Since the introduction of the electrics some people proposed to allow designing larger circuits off the world, and encapsulating them in a single element. Because I don’t want to turn the game into a piece of electronic circuit simulation software, this is over the top.

But the idea is not completely without merit. There is a subset of circuits that are easily described by nothing more than a bunch of checkboxes, and can perform the same task as a multi-logic-gate device. Enter the truth table.

Truth table is a way of describing what output a logic device produces for a given set of inputs. Here’s one for the AND gate:

Input 1 Input 2 Output
0 0 0
0 1 0
1 0 0
1 1 1

As you can see, this is an incredibly simple concept. On the left are all possible 4 input combinations. The right column gives a desired output for the given set of inputs.

Of course, it only works for stateless devices. Any device that contains any form of memory (e.g. a SR latch, a delay, or even simply is looping on itself creating feedback) cannot be described that way. That’s obvious, because the output of such device also depends on its internal state, not only on the state of the inputs.

Truth table circuit is an implementation of this idea. It has 4 inputs and one output (output is at the back, you need to use a wire-through-block to access it).

In the game, once you have it in your hand, press the edit button, and you get this interface:


Truth Table Editing Dialog

There are 16 rows containing all possible combinations of 4 inputs. Each row has a checkbox next to it. Tick it, and the marked combination of inputs will produce a logic “1” on the output (1.5V). Unticked ones will produce logic “0” (0V).

In brief, truth table lets you condense bunches of AND, OR, XOR, NOT gates into one convenient element.

  • What to do if your device has more than 1 output? Simple, you just need multiple truth tables, one for each output.
  • What to do if your device has more than 4 inputs? That’s tougher. You need to split the device into a hierarchy of sub-devices, and again use multiple truth tables.
  • What if your device has less than 4 inputs? Trivial, don’t connect the unused input and leave the relevant checkboxes unchecked.

That’s pretty much it. Hopefully truth tables will let you build simpler, smaller and more powerful devices!


  1. Posted October 16, 2013 at 13:49 | Permalink | Reply

    Thats most useful circuit.
    Now i can create different types of flip flops.
    Thank you so much kaalus,thank you.

    • Posted October 16, 2013 at 13:50 | Permalink | Reply

      Im first to comment

      • Posted October 17, 2013 at 08:54 | Permalink | Reply

        We don’t care who first!! Stop commenting like ‘ i’m the first to comment’…

    • Posted October 16, 2013 at 23:41 | Permalink | Reply


      African wild cat:
      Spawns in desert. As abundant as coyote packs. Tamed with fish. Will randomly and spoon death drop a claw.

      Already in game but should be tameable with raw bacon. Fetch sticks when thrown

      Already in the game but should turn into minatars on full moon ONLY. They cannot be ridden at that time.

      Already in the game but should turn into half man half horse creature (I forget name) on half moon ONLY. Cant be ridden at that time. White horses turn into Pegasi on half moon. They can be ridden.

      Spawn in oceans only. Once ridden twice, dolphin is considered tame and can be ridden under your control. Same mechanics as a horse, just faster in water and dies on land.

      Sea turtles:
      Rare, like white bulls. Drop shell, meat, and egg apon death. Egg can be hatched to grow a tamed turrtle. She’ll can be used for Amor and tools.

      As you said before kaalus, trunks could be a major bug creator, but just as a suggestion, you could ride by putting 2 saddles on. Ivory risk dropped soon death can be carved into weapons and statues.

      Giraffe (special saddle)
      Ostrich (as mentioned before not trying to be pushy or anything)
      Bulls (will randomly try to kick you off)
      Dolphins (will try to kick you off and run away like wild horses intill ride in twice.)
      Elephants (two saddles needed

      Horses (will show flowers, hearts,… in that paint color)
      Wire through blocks (except Simi conductor)
      Stairs (of paintable materials)

      Giraffe harness:

      Saddle. Nothing. Nothing
      Woodslab Nothing. Nothing
      Saddle. Nothing. Nothing

      It works kinda funny.
      1. Tap giraffe with harness in hand
      2. There will be two platforms, on on top (with wood slab beneath), and one on the actual giraffe
      3. Tap the top platform or bottom saddle
      4. The rest works like normal horse

      Rope. I’ve heard of rope crafted from plant material, so it will save you some time vs. making a new animal and sissors

      Wild rye. Wild Rye. Nothing
      Wild rye. Wild rye. Nothing
      Wild rye. Wild rye. Nothing

      Rope has 2 uses. Boats and animals
      1. Place rope in hand and tap animal/boat
      2. Tug animal/boat to nearest fence post
      3. Tap fence post. The animal/boat is now tied to the fence post and cannot move vary far. On rare occasion, your animal will break free. Boats on even rarer occasion.
      4. There is a 5.5% chance your animal is claustrophobic. If it is, it increases the chances of it breaking free by 30%
      5. To untie animal just “mine” the rope or fence post. This will untie animal or boat. If animal is claustrophobic it will run away immediately.

      Iron boat. Moves faster, can place chest inside, and is more durrible.

      Crafted like boat, but with iron.

      Fishing rods:
      Used to catch fish

      Nothing Nothing raw bacon/ fish
      Nothing rope Nothing
      Stick Nothing. Nothing

      Donkey saddle bags:
      Store things and placed on with saddle. Can be removed by mining bags

      Chest Nothing Chest
      Nothing saddle Nothing
      Nothing Nothing Nothing

      • Posted October 17, 2013 at 04:10 | Permalink | Reply

        Hmmm…. Nothing in your list is a electronic…. Interesting… I guess that speaks for itself.

      • Posted October 17, 2013 at 08:56 | Permalink | Reply

        Stop asking Kaalus too add this and that. Kaalus need to think about older devices too & it will lag a lot !

      • colepanzer
        Posted October 17, 2013 at 15:20 | Permalink | Reply

        Wow! That would be awesome! Great Job!

  2. Posted October 16, 2013 at 13:56 | Permalink | Reply

    Love it! Can you adds ropes to tie to fence posts or h

  3. Posted October 16, 2013 at 13:59 | Permalink | Reply

    Im starting to build 1024 bit programmable rom memory for my computer that can hold 128 operations data and its dual read.

    • Posted October 16, 2013 at 21:33 | Permalink | Reply

      Do you mean RAM or does ROM stand for Remotely operated memory

      • Posted October 17, 2013 at 21:35 | Permalink | Reply

        Its rom.rom stands for read only memory.
        But my rom in game is re-programmable by manually turning on and off 768 sr latches.
        Memory unit has 4 sectors and contains total of 1536 logic gates:D
        Its 12 bits wide,8 bits for data and commands and other 4
        for some functions(editing registers) and identification of 8 bit data.

  4. Posted October 16, 2013 at 14:34 | Permalink | Reply

    • Posted October 16, 2013 at 14:35 | Permalink | Reply


      • Posted October 16, 2013 at 15:28 | Permalink | Reply

        I hope this update gets released soon.

        • Posted October 16, 2013 at 16:04 | Permalink

          So do I.

        • Posted October 16, 2013 at 16:15 | Permalink

          I completed memory :(but i cant make it this huge.I made it 256 bit(32 byte) it still can hold “large” amounts of data .program memory will use sr has 32 wires to select wanted line and 8 outputs showing data on current selected gonna build 5 bit program counter and 5 to 32 custom decoder.
          Programming will be just have to know its instruction set.
          Clock for this computer will be many many times faster than fastest minecraft computer has:D

  5. Posted October 16, 2013 at 15:52 | Permalink | Reply

    Kaalus if its possible, could you create a gate that switches signals upon button presses? Like let’s take the AND gate, I connect it to a circuit and then to a screen. I use a set of buttons to control the movement of light on the screen (like road rage 2 ten mile by mgblitz81) and I press a separate switch to connect a different circuit but without having to create a circuit just to switch between games. Could you invent a gate that switches signals upon button presses? Thanks. :)

  6. mrjustplaying
    Posted October 16, 2013 at 15:58 | Permalink | Reply

    Wow! Simple way to build our own logic gates – and with up to four inputs!

  7. Posted October 16, 2013 at 16:10 | Permalink | Reply

    am not good with electrics in the game but i’am very good at building and creating , i could use this a computer monitor when furnishing a house

  8. dangercrafter
    Posted October 16, 2013 at 16:57 | Permalink | Reply


    • dangercrafter
      Posted October 17, 2013 at 08:32 | Permalink | Reply

      We need dogs!

      • Posted October 17, 2013 at 15:34 | Permalink | Reply

        allready got coyotes!!!!!!!!!!!!!!!!!!!!

        • dangercrafter
          Posted October 19, 2013 at 08:23 | Permalink

          So you are saying coyotes are dogs. Well, my dog doesn’t look like a coyote at all.

          We need dogs, coyotes are not dogs!

  9. Posted October 16, 2013 at 17:03 | Permalink | Reply

    That i was allways wanted

  10. Posted October 16, 2013 at 17:12 | Permalink | Reply

    i can’t wait!!!!!!!!!!!

  11. Posted October 16, 2013 at 17:20 | Permalink | Reply

    Have not come back to this game since the horses and WOW that is a lot of new stuff. Is there a guide to all of the electronics ? If not that would be extremely helpful.

  12. Posted October 16, 2013 at 18:22 | Permalink | Reply

    boring … It would be better to make a plane, a car, a bicycle.

    • Posted October 16, 2013 at 21:28 | Permalink | Reply

      What? Dont add planes, cars, and bicycles. Only if there were mods. Survivalcraft isn’t a city game where people ride in cars and planes. Its for “survival” its in the name. Maybe if he added mods then it would be better for you to customize your gameplay. But I don’t think everyone should suffer from the unrealism of the bad idea some stranded person riding a plane. You are STRANDED. Not in New York city with planes and cars. No planes please. :)

      • Posted October 17, 2013 at 00:39 | Permalink | Reply

        the veicles is a bad idea,ok
        but,this is a survival game not a eletrical simulation game,we can have alpaca,turtles,snakes,more foods, and very survival things,that is a bonus.

      • Posted October 18, 2013 at 08:06 | Permalink | Reply

        I do not agree with you. It’s not a musical and electronic emulator. People are interested in the creation of maps to play in creativity. People like to create worlds. And then it would be nice to fly on a plane built around the map. People want more interior items. People want to multiplayer. Kaalus is moving in the wrong direction. Personally, I’m not interested mechanisms and the creation of music in the game.

        • Posted October 18, 2013 at 22:54 | Permalink

          Maybe you can make a mod for it then. Alot of people have made survivalcraft mods. Like the werewolf mod and megacraft mod for survivalcraft. But I don’t think everyone should suffer from the not so good idea you have for planes. Besides he’s making the game better before multiplayer comes.

  13. Posted October 16, 2013 at 18:44 | Permalink | Reply

    Man I just want to hear more about gameplay not just electronics the whole time but you should have a recorder to record things like surveillance or something

    • Posted October 16, 2013 at 23:44 | Permalink | Reply

      People like you don’t like electrics because you don’t understand them. Once you do, survival craft is the best game you’ve ever played. Its like coding where you can do nearly anything. But electrics has its limits too. I’ll post a world on here for everyone made by mgblitz81 that really explains with detailed info about electrics and basic circuits with examples just to get you thinking about the possibilities of electrics. :)

  14. Posted October 16, 2013 at 19:07 | Permalink | Reply

    Boring? Hmm I guess you are not mature for say that!

  15. Posted October 16, 2013 at 20:21 | Permalink | Reply

    Kaalus, I have been thinking, is wireless possible? I have the idea that you could create 2 more devices. One that you connect to whatever you want it to be, the other gives power. It would minimize the need to use tons of wires with large projects.

  16. Posted October 16, 2013 at 20:23 | Permalink | Reply

    I hope you gwt what I mean because I can’t think of a way to explain it correctly. I have a better explanation on my blog.

  17. Posted October 16, 2013 at 21:17 | Permalink | Reply

    KALUS the last two posts have been in computer language please use English !

  18. Posted October 16, 2013 at 21:22 | Permalink | Reply

    You should add us ability to record .

  19. Posted October 16, 2013 at 21:46 | Permalink | Reply

    I realized we have four hearts. Four slots next to hunger slot. So we must be getting 4 armor. 1 armor for each of the hearts. Helmet for top heart, chestplate for next , leggings, and boots for the lower two hearts. Can’t wait for the armor one of these updates. :D

    • Posted October 16, 2013 at 23:51 | Permalink | Reply

      Armor won’t make sense… Why? Because Kaalus wants survival to be more difficult guys… So don’t ask for weapons and armor…. It the last thing on his mind. The slots are more likely going to be for clothing rather than protective armor.

      • Posted October 18, 2013 at 01:02 | Permalink | Reply

        Kaalus mentioned ARMOR a while ago. That’s what the slots are for.

      • Posted October 18, 2013 at 01:07 | Permalink | Reply

        Protective clothing. I’m sure clothes won’t be just for looking nice, stylish, and cute for the animals. I’m sure he will add some protective purpose to clothes rather than looking cool with brand new clothes in the middle of nowhere. :D

  20. Posted October 16, 2013 at 22:05 | Permalink | Reply

    Dear kaalus can you add mods and mod making into the game if you don’t know mods are downloadable content that allows you to add your own features into the game you could make a new app called survival craft mod maker this way the public could make there own mod for example my mod would be called galactacraft I would add space ships into the game and you can fly to the moon with it how would I do this I would make it so that when you got to a certain hight in the space rocket you enter a new world made of a new block called moon stone or if I feel like it cheese so please add mods and mod making into survival craft and it saves on us begging you in posts like this one for new features anyone with a comment on this write in the post right here or Email me at I did want to make this post extra long so that people would notice it thanks

    • Posted October 17, 2013 at 06:29 | Permalink | Reply

      “If you don’t know…” Kaalus is too polite, so I’ll be offended for him. You honestly think the man that wrote this entire game doesn’t know what a mod is??

      • Posted October 17, 2013 at 21:09 | Permalink | Reply

        Awww, but he did write a very polite note and he could be a kid so I doubt Kaalus would be offended.Hell, I had no idea what a mod was until I played MC last year – or least I had no idea how widespread and involved they were or how huge the modding community was/is.

    • dangercrafter
      Posted October 17, 2013 at 08:35 | Permalink | Reply

      There’s already mods.

      • Posted October 18, 2013 at 21:34 | Permalink | Reply

        Can you put a link in a post that directs us to a site where we can get mods

        • Posted October 18, 2013 at 22:59 | Permalink

          Go to google images and type survivalcraft mod megacraft. Or survivalcraft werewolf mod. There will be a link to lefora when you click the pictures. you will then be able to talk to the people who made the mods and ask how to get them.

  21. Posted October 16, 2013 at 22:11 | Permalink | Reply

    Kaalus you should add streams to the world generation to have fresh water bass in, and I know this soundds a bit minecrafty but you should also add fishing poles to fish

    • Posted October 16, 2013 at 22:13 | Permalink | Reply

      And you should do some videos on how to build this stuff because it is kinda useless if almost everyone doesn’t understand the electrics and your time is down the drain

  22. Posted October 16, 2013 at 22:43 | Permalink | Reply

    So is this like a password lock? If not can we get one?

    • Posted October 16, 2013 at 22:44 | Permalink | Reply

      My comments are now posting! :D

      • Posted October 16, 2013 at 22:46 | Permalink | Reply

        OLD if u know this kaalus, but there is a glitch on your blog and your blog only, that when people click “Post Comment” the comment doesn’t appear anywhere! It just disappears! Alot of people have been having t his problem and I don’t know if you recieve the comment when they don’t appear. Do u k n ow anything about this?

  23. Posted October 16, 2013 at 23:18 | Permalink | Reply

    Too many word cant understand … ??????????????????????????????????????????????????????????????????????????????????????? o_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_Oo_OB-)o_Oo_O:-D:O:-DX-( :-*:-D:-/ :-*:-X:'(:-/:-D:-X:'(:-/ o_O:-X :-X:-\o_O:-V:-*:-XX-(:-V:-*:-X:-V:-X:OX-(XD:-/:-D:-3XDX-(:-V:-X«¿¥§£§€>_§^{¢^¥{>`¥}>©§¥₩©§₩¶[{¢¶₩[{™™[}₩¶[{¢¡^§₩¥§¢·

  24. Posted October 16, 2013 at 23:30 | Permalink | Reply

  25. Posted October 16, 2013 at 23:31 | Permalink | Reply

    Sorry it want let me past in the forum

  26. Benny Valdez
    Posted October 17, 2013 at 00:30 | Permalink | Reply

    Wow. Very cool I have a question, is it possible you can add cross bows in 1.24? A sheep can be added or a spider and use spears as ammo. That would be cool! From Benny, a big fan of kaalus.

  27. Posted October 17, 2013 at 00:31 | Permalink | Reply

    the game already is an eletronic simulation in 1.23 kaalus,really,that aren’t useful,i will use 30 blocks,5 eletric gates and wires just for make a boring music?
    that is a survival game,if want a eletronic simulator i download it,this is survival craft,not eletric craft.
    i am disapointed with 1.23
    that update is terribleeeeeeeeeeeeee!!!!!!!!!!!!!!!!

    • Posted October 17, 2013 at 03:28 | Permalink | Reply

      Sorry but I agree respectively…. So far I’m only looking foward to the corner block, seeing far and wide, the new fish and I guess the donkey… I wish there were more blocks, items in this update. I’m looking foward to 1.24, I hope there’s more blocks and items to work with then, and I hope it Dosent take as long as 1.23 is going. I’m going to have to put Survival Craft down for now. I’ve been following this update well over 2 months now, it’s been very frustrating, following it by the hours, days, weeks and several months now.

      • Posted October 17, 2013 at 12:54 | Permalink | Reply

        I’monitoring to say anything intill I get the FRIKEN password gate!!!!

      • Posted October 17, 2013 at 21:06 | Permalink | Reply

        A friend of mine explained the truth table in a very simple way to me (sorry Kaalus – I didn’t understand the post above) and now I’m actually excited about the logic update because I think this circuit alone will make complex traps & puzzles possible in adventure mode. I’ve written more here:

        I would like to see a mechanical update in the near future so we could use all this powerful computational power with blocks that could manipulate the world so that in the survival game we could look at building automated mines and transport systems as that would seem to me to be the next logical step (ho ho – see what I did there!).

      • Posted October 18, 2013 at 21:21 | Permalink | Reply

        i feel tha same way,

  28. Posted October 17, 2013 at 04:12 | Permalink | Reply

    Good bye guys, Good Bye Survival Craft. See you guys upon 1.24.

  29. Posted October 17, 2013 at 04:16 | Permalink | Reply


  30. Posted October 17, 2013 at 11:44 | Permalink | Reply

    kaalus could you add streams to the terrain generation so that fresh water bass could spawn there, and i know this sounds kinda like mc but could you add fishing poles or something like that, also you should add a few videos going into depth about the electronics so not every one or most everyone is confused.

  31. colepanzer
    Posted October 17, 2013 at 15:24 | Permalink | Reply

    What we need is kelp for the ocean. It can be used as compost for crops and help trees grow better. Maybe even make a kelp block which you can sleep on! But my point is is that the oceans are incredibly barren and need some spicing up. But this update is going to be amazing with the new bass Kaalus! Great job!

  32. Posted October 17, 2013 at 15:35 | Permalink | Reply

    please look at my blog

  33. Posted October 17, 2013 at 19:48 | Permalink | Reply


  34. Posted October 17, 2013 at 23:28 | Permalink | Reply

    Hey kalus, I know you probably heard this a million time but in 1.24 can u plezzzz focus on multiplayer? Like make individual servers for like 2$ ezy way to make more money! Plus, I’ve always wanted to play sc together with my step brother =)

  35. Posted October 18, 2013 at 00:22 | Permalink | Reply


    • Posted October 18, 2013 at 01:15 | Permalink | Reply

      I found that megacraft the survivalcraft mod is getting minecarts and rails. I wanna know where to get it. I saw it on lefora.

  36. Posted October 18, 2013 at 01:11 | Permalink | Reply

    I heard on lefora that megacraft mod is getting worked on. So there will be TRACKS AND MINECARTS IN THE SURVIVALCRAFT MOD. I hope he adds nether portal.

  37. Posted October 18, 2013 at 02:04 | Permalink | Reply

    headburro antfarm, nicely done on explaining the truth table. That’s actually kinda cool now, I still won’t use it ever for single player. But its potential worth noting for adventure mode. Bring on the glass panels and hand rails for stairs and I’m happy. and maybe having leaf blocks go away when a tree is gone

    • Posted October 18, 2013 at 06:19 | Permalink | Reply

      Hi jay, hopefully these changes will be useful in the survival game in the future, maybe if moving blocks such as pistons are added.

  38. Posted October 18, 2013 at 06:23 | Permalink | Reply

    Reblogged this on wportillostar and commented:
    Fave game

  39. Posted October 18, 2013 at 16:54 | Permalink | Reply

    When is the update coming out? I know this one is the biggest one you have ever done but it would be nice to get it. :)

  40. Posted October 18, 2013 at 18:16 | Permalink | Reply

    update taking to long!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

    • Posted October 18, 2013 at 23:06 | Permalink | Reply

      I hope it takes longer so he can add more stuff. Like VILLAGERS. Do you guys really want the update out now when all we got is donkeys, fish, and electronics. I’m sure he will add a cool feature in the end of the update before releasing this one. Did you guys forget that he’s working on generated structures? Maybe villages and mineshafts this update. :D

  41. Posted October 18, 2013 at 18:36 | Permalink | Reply

    Wow please update zo fast you can. I want do it self to :-) you have so many things post…awesome!!!!

  42. Posted October 19, 2013 at 00:20 | Permalink | Reply

    How do u trackback?

  43. Posted October 19, 2013 at 04:04 | Permalink | Reply

    If kaluss adds npcs or multiplayer he should make it so two people can ride horses back and any other ridible creature
    and that delay gates can have an in and out put on the bottom like when put on wire through blocks.

  44. Posted October 19, 2013 at 11:43 | Permalink | Reply

    Whenever I try to fertilize my soil the saltpeter will not break. It is very frustrating and I hope Kaluss fixes this.

  45. Posted October 19, 2013 at 14:41 | Permalink | Reply

    yeah the electrics make no sense.

2 Trackbacks

  1. […] Kaalus has unveiled yet another of his updated electric logic elements coming in the next update, the truth table. […]

  2. […] my last post on this subject I said that I had no idea what Kaalus was on about in his post. I still don’t, but my old SL mate Dale has shown me the light and in doing so opened my eyes […]

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