Numberabbey - 67 Early Spring by Kanddak

Map Description:

I built an eight-bit ripple-carry adder over the weekend and have just started the digging to take it up to sixteen bits.. I've seen a few theoretical designs for full adders on the wiki and such, but never a complete system.
See it in action here:

Point of Interest: Adder components

This is the business part of the fort. There's a half adder on the far right and then seven bits of full adders. To the south are some excavations for the impending expansion to sixteen bits.

Most of the up staircases are for dwarf access but the topmost ones are the water inlets.
The paired down staircases are the drains. The pressure plates on the right sides of the adders are the sums and the ones on the left are the carries.
Everything of the same color in each adder shares a trigger. The red and blue buildings are triggered by the input levers, and the green ones by the carry pressure plate of the adder to their right.
The brown doors are not linked to any triggers and are only there for the convenience of dwarves.

Those are one-tile drawbridges in there, which are perfectly like inverse floodgates, except that whereas floodgates only annihilate water when they close, the bridges would crush anything that got caught in them ;)
The only inconvenience with them is that it's impossible to tell directly whether they're open or closed; you have to deduce it from the state of the nearby floodgates and the assumption that everything is linked up correctly.

The adders are designed so that whenever the water has a path from the inlet to one of the pressure plates, it doesn't have to travel diagonally, and therefore maintains pressure. The drains are deliberately diagonal, so that the pressurized water piles up on the plates and triggers them, and drains more slowly than it accumulates.

The next level up is the access hallway for construction and maintenence. All of those dwarf-access stairwells are covered with hatches, although some of them didn't show up in the image export. This is necessary to keep the pressurized water from circumventing all of the logic and always triggering all outputs by going through the access tunnels.

There were a number of other considerations in the design which I'll write about in more detail some day. Suffice it to say that I abandoned two forts before starting this one because of irrecoverable design flaws. - Kanddak

There are 11 comments for this map series, last post 2009-03-31

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Submitted by: Savok - 2009-02-01 to 67 Early Spring


Submitted by: blue emu - 2009-02-02 to 67 Early Spring

The next logical step is to design a Dwarf Fortress tunnel-system that will act as a computer powerful enough for you to play Dwarf Fortress!

Submitted by: Nahkh_ - 2009-02-03 to 67 Early Spring

This is very impressive. I was designing one myself but you beat me to it. Oh well. I still have a few secret projects underway.

I particularly like the compactness and effortless extension. The color-coding is a nice addition.

Submitted by: tsen - 2009-02-05 to 67 Early Spring

Holy cripes.

Submitted by: KaelemGaen - 2009-02-06 to 67 Early Spring

Do you have a video of it working? or is it just the layout proof of concept?

Submitted by: Kanddak - 2009-02-06 to 67 Early Spring

Yes KaelemGaen, the demonstration movie is here:

Submitted by: Dakira - 2009-02-06 to 67 Early Spring

*Astounded* Wow, when you first said adder in your earlier works, I had no idea you meant it literally.

I might look into trying DF computing; ideas that popped into my heard were:
- Rather then gears be the output, why not show it with water levels. Have individual one space channels that act can act as digits. It might be limited to a non-base-ten standard, but interesting to me at least.
- A veritable "Dwarven Water Clock". Imagine it, able to tell you the DF time for day, month, and year.

[Message edited on 2009/02/06 at 08:33 by Dakira]

Submitted by: Sukasa - 2009-02-07 to 67 Early Spring

In your video you have eight side-by-side gear assemblies that apparently don't connect to each other - how'd you manage that? I wasn't aware that was possible o_O

Submitted by: Kanddak - 2009-02-11 to 67 Early Spring

Dakira: You might do that by having the output gears power pumps. You may be interested in my design for a 7-segment display or the associated forum discussion.

Sukasa: The output gear assemblies do connect to each other when they're engaged, but they are disengaged until the correct pressure plates are submerged.

Submitted by: Barbarossa - 2009-02-13 to 67 Early Spring

Holy addition! can it do subtraction?

Submitted by: crash2455 - 2009-03-31 to 67 Early Spring

Binary addition is binary subtraction, it's just how you interpret the bits.

It's too bad you can't assign multiple pressure plates to set something off, or else the drawbridge seven-segment display idea wouldn't be so complicated.

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Don't have Flash?
You can download the compressed map file: 2009-02/kanddak-Numberabbey-region8-67-3142.fdf-map but you will need the .NET version of SL's DF Map Compressor to convert to the .PNG image format.