Hein (fub) wrote,

  • Mood:

Open Source Random Number Generator

I found a hardware random number generator on the web, and I had planned to use that (see the schematic and board layout here). Basically, by not connecting the collector of a 2N3904 transistor, you introduce noise into a system, which is then rectified and amplified and sampled to provide random bits.
The drawback of this system is that it uses a lot of parts (and thus a lot of space and traces), and that it has to be run at 12V. All of the other stuff runs on 5V, so you have two parts of a schematic that interact, both running at their own voltage level.

Two days ago, the Make blog posted a link to the ORB (Open Random Bit), a random number generator housed in a single, 8-pin chip. An 8-pin Microchip microcontroller, to be precise. The 12C671, to be more precise. Which is now deprecated and succeeded by the 12F675 -- of which I have quite a few lying around.
The algorithm is, apparently, so random that it is in use in various security and gambling applications. It's GPL licensed as well. And with a microcontroller that works on 5V like the rest of the parts and only 8 pins, the layout will be much simpler.

So the past two days I have been porting the code over to the 12F675. I will have to test the code, but first I have to build a toolchain on Ubuntu to work with my programmer.
Tags: electronics project, random led rail

  • Things that happened this week

    A power interruption. We had gotten a letter from the company that manages the power lines that they’d be working on the infrastructure on…

  • Misc

    I guess a Friday Five is better than nothing. 1) What’s the best customer service experience you’ve ever had? Being loaded up in the…

  • Taking stock

    One of the biggest chores in reconstructing our living situation is putting the books in the new bookcase(s). When we brought the books and the old…

  • Post a new comment


    Anonymous comments are disabled in this journal

    default userpic

    Your reply will be screened

    Your IP address will be recorded