We normally try to be descriptive with our titles. But when that statement pops out of the narration with notable excitement it made us chuckle. This installment of Retrotechtacular is a promotional video for the Blit. It’s a graphics-based hardware terminal for Unix systems. It’s biggest boast is the ability to run (and display on screen) several different programs at once — an activity called multiprogramming. But there is also the “digitizing mouse”. On board is a 68000 microcprocessor 256k of RAM (they call it a quarter meg), and connects via RS232. The screen is 800 by 1024; that’s right, it’s a portrait orientation.
Notable in this episode are some classic eyeglass frames, and rad synthesizer sounds for scene transitions. Whatever happened to videography technique that uses a dimwitted companion to ask that all-knowing narrator stupid questions?
Continue reading “Retrotechtacular: The Blit has given me access to the power of multiprogramming!”
I always have! I don’t know why, but I like the idea of using an oscilloscope screen as a general use video display. Why not? In my case it sits on my desk full time, has a large screen area, can do multiple modes of display, and is very easy control.
Making an oscilloscope screen do your bidding is an old trick. There are numerous examples out there. Its not a finished project yet, so be nice. It is actually rather crude, using a couple parts I had on hand just on a whim. The code is a nice mixture of ArduincoreGCCish (I am sorry, still learning), and includes the following demos:
- Simple low resolution dot drawing
- A font example
- A very quickly and badly written demo of pong
The software runs on an Attiny84 micro controller clocked at 16Mhz, paired up with a Microchip MCP42100 dual 100k 8 bit digital potentiometer though the Attiny’s USI (Universal Serial Interface) pins. This is a fast, stable and accurate arrangement, but it requires sending 16 bits every time you want to change the value of one of the potentiometers so its also very piggy. I was just out to have some fun and did not have a proper 8 bit DAC. This was the closest thing outside of building one.
Join us after the break for pictures a (very) brief video and more.
Continue reading “Want to play Pong on your Oscilloscope?”
[Andrew Rossignol] was curious one day and decided that he wanted to display graphics on an oscilloscope after playing around with the X and Y inputs.
[Andrew] started out with a resistor ladder on the DAC of his AVR Butterfly. He was able to to draw a line on the oscilloscope’s screen but bandwidth limitations forced him to reconsider his approach. A friend wrote a Python script to generate C code so the ports of the Butterfly can be toggled. After getting the Butterfly to generate a voltage for every non-white pixel, [Andrew] was impressed with the results so the code was modified determine the brightness of each pixel. The setup managed 10 shades of gray and careful selection of what graphics to post on the build log assured the project a little bit of blog cred.
There are a few ways to display a picture on an oscilloscope, like plugging the Hsync and Vsync into the inputs of a scope. Except for a few music visualizations, we haven’t seen a scope display generated from a microcontroller. Great work [Andrew], but we’d like to mention there’s a grayscale Hack a Day logo from way back when.
Check out a video of [Andrew]’s oscilloscope after the break.
Continue reading “Displaying graphics on an oscilloscope”
Our initial view of the Spy Video TRAKR “App BUILDR” site had us believing this would be an internet-based code editor and compiler, similar to the mbed microcontroller development tools. Delving deeper into the available resources, we’re not entirely sure that’s an accurate assessment — TRAKR may well permit or even require offline development after all. Regardless of the final plan, in the interim we have sniffed out the early documentation, libraries and standalone C compiler and have beaten it into submission for your entertainment, in order to produce our first TRAKR hack!
Continue reading “Spy Video TRAKR: software and first hack”
The contest runs through September 10th, allowing ample time to come up with something even more clever. Whether he wins or not, we think [Steven] deserves special merit on account of having one of the most stylish blogs in recent memory!
[Keith Peters]’ blog Art From Code is devoted to his beautiful graphics from computer source code, also known as generative art. Although [Peters] is reluctant to reveal his source code, algorithmic graphics can be created with the help of tools like ActionScript, Flash, and Flex. There are some great tutorials that can start you on the path to making your own evocative art.
[Kieth] picked up an Infocus projector only to find that it needed some repair. The polarizer on the blue light path was toast. When he parted out an Optoma projector he scored a polarizer that was just about right for the repair. It’s a good read even if you don’t have a projector in pieces at the moment. He ended up bending the mounting bracket a bit to hold the filter and got his projector fully up and running again.