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Our Universe is a Simulation

 The more we study the world around us, the more we learn about the inner workings of the universe we live in. As computing power grows, more and more physicists have given thought that our world and the universe we live in, is nothing more than a highly sophisticated simulation, and that us little self-aware humans are just players in the computer-generated world we live in. Much of the physics ideas presented below are taught starting in high school, and again in college where higher levels of mathematics are used to solve the details. None of this is secret, but just not discussed outside the halls of academia.  Following are some of the ideas that show our world to be a computer simulation. 1. Our universe is pixellated. In the early 20th century a very bright man by the name of Max Planck reasoned out that space (and therefore everything) is discontinuous. If you look closely at an older TV screen or computer monitor, the type with a glass tube, you will see the image becomes a se
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nano80 - An Arduino nano based 8080 Simulator

Overview I wrote my first 8080 simulator about 15 years ago in c for my x86 based PC. It worked. I posted the code and several others used the source for their projects. I hadn't thought about it for a while, but on whim I started thinking about how small a footprint I could make an 8080 type single board computer, something like the microprocessor trainers we used in college. The nano80 is the result. I honestly didn't think I could fit an 8080 simulator on an Arduino nano. I didn't think there was enough ram to be useful (there wasn't) nor did I think it would be fast enough (it really isn't). But as an 8080 test bed it works better than I hoped. I have LED's for a display port, toggle switches for an input port, a 1x8 LCD display for the address and data output for programming, and 6 momentary push button switches all combined to give me a programmable front panel. At first I used the internal ram of the nano as my main memory. That gave me about 700
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Raspbian and CUPS are complete and utter crap.

So, for a few months now, I've been trying to get CUPS (print driver) working correctly under raspbian. These are the issues I'm having: CUPS sends output to the printer, but several of the first lines are missing from the printout. The source file looks just fine. CUPS has specific drivers for the printer I'm using. I've installed these, and they work. But - The fonts used for the print driver are so horrible to look at, they are completly useless. God awful to look at. CANNOT BE DESCRIBED JUST HOW GOD DAMNED UGLY THEY ARE. And the printout still misses the first few lines of the file output. I'm guessing the pre-pubecsent teen that wrote the fonts and driver had never seen a printer before. Opened a ticket with debian about the problems of missing lines. After a few e-mail exchanges, we decided that debian doesn't care and won't care in the future. Maybe he was the author of the GOD AWFUL font set. Never had this problem with Slackware..
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Using the PMC-20 Minicomputer - An example session

This post is a little different. It shows a typical login session on the PMC-20. You start by connecting via a ssh session: Workstation1:~ $ ssh kurt@pmc20 kurt@pmc20's password: Last login: Fri Jan 26 16:24:37 2018 from pi1   #     # ######  #######     #######  #####   #####   ##   ## #     # #           #     # #     # #     #   # # # # #     # #           #     # #             #   #  #  # ######  #####       #     #  #####   #####   #     # #       #           #     #       #       #   #     # #       #           #     # #     # #     #   #     # #       #######     #######  #####   #####       --- Welcome to MPE on the PMC-20 --- To view available commands type 'commands' at the prompt. For command help, type 'help [command]', or just 'help'. You will be logged out after 20 minutes of inactivity. Assigned JOB number 114 ~/kurt> commands *** MPE Built-in Commands *** cd               change directories help             show this help file exit 
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PMC-20 updates

A few notes on my mini computer. I re-wrote MPE (the user shell/commands/accounting system) on and off over the last few months. MPE is now version 3.02. I’ve added a lot of user programs and added features to the utilities I already completed. I’m finishing up a line editor that’s somewhere between ED for the pdp-8 and TECO. All the user utils  (cd, copy, attach, type etc) are multi-user safe and as optimized as I can make them. I found out about the Linux kernel  atime bug that breaks some of my system monitor stuff. Too bad the kernel devs want to keep it broken. Oh, well. I made a file system change that made a 200% speed up to the user experience. Very happy with that. I wrote a couple drivers for low speed and high speed paper tape readers. I wrote a tape drive driver. I can’t find my 500 mb tape drive so I emulated one using sequential files on various media. Really happy with it - I can type “tape save” and save versions of software in seconds. Lots faster than reel
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Lightwave Communications

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It is possible to transmit audio (and data, video etc) across medium to long distances by modulating light with either high power LED's or lasers. Equipment made by others has effective ranges well over 100 miles. The optical portion of the equipment I made is designed for shorter ranges. The electronics portion of the above transmitter will drive any optics. For my optics I use a 3 watt red LED or 20mw red laser driven with a 20KHz pwm signal modulated by one of three sources: a front panel microphone,  line-in (1/8"/3.5mm stereo jack) and an internal linux-based computer (raspberry pi zero version 2). The PWM modulator is a 12F683 PIC based microcontroller from microchip.com. Here is a youtube video showing the system described here: https://youtu.be/ujk117eTPjM The pic microcomputer has 8 pins, and is programmed in assembly. I feed in audio through an audio preamp (2N3904 transistor) which then goes to a op amp and a low pass filter at 4khz. From there it goes int
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Large Format Pinhole Cameras

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Building your own camera. Many people built a pinhole camera while in grade school or maybe as late as high school. It's a novelty, and the results reflect that. I built one using the carboard box a pack of 35mm film came in, cut out the end and put a piece of aluminum foil with a hole punched in. It produced an image, if you squinted just right, and the results reflected that. The project was never duplicated. Until last week. There are many forums dedicated to pinhole photography. I never looked into them. However, I was reading some text books I got on Amazon ($0.01 each, $3.99 shipping, brand new 1000 page physics texts) about light and came across a few things. This got me thinking. Seems there are certain ratios, and when followed, give reasonable focus to light when followed. In the camera world, there is a thing known as an f stop, or the amount of light allowed in by a lens.  The f stop is determined by the diameter of the lens and the distance to the film plane
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