Raspberry Pi Finds Itself Inside A TRS-80 Model 100

This TRS-80 Model 100 is a lot more powerful than you might think. That’s because [Karl Lunt] is using it as an enclosure for his Raspberry Pi board. Since the ARM-powered device comes sans-enclosure it’s fun to see a retro choice like this one. And having had to go out and buy a USB keyboard to use our own RPi, we appreciate [Karl’s] solution for using the original keyboard as an input device.

Above you can see that he’s using an LCD tv as the display. For now that connection is made using the composite video output, which explains the fuzzy image. To the right of the TRS-80 a standard wall wart connects to the barrel jack to provide power. [Karl] scrapped a USB cellphone charger in order to connect from the barrel jack to the micro-USB jack on the Pi board. The ribbon cable to the left lets him get at the I/O header without opening the case.

In order to use the keyboard he patched into it with a Teensy board. That connects to the USB port on the RPi, sending HID keyboard commands based on what it received from the user. We like this option as it give you the ability to pre-process keystrokes (ie: you can code your own custom macros that the Teensy will listen for). Right now the Model 100’s LCD screen isn’t hooked up but he may add that in the future.

Hackaday Links: June 12, 2012

Amazing 3D rendering in real-time

Ah, the 90s. A much simpler time when the presenters on Bad Influence! were amazed by the 3D rendering capabilities of the SGI Onyx RealityEngine2. This giant machine cost £250,000 back in the day, an amazing sum but then again we’re getting nostalgic for old SGI hardware.

Well, Mega is taken… let’s call it Grande

[John Park] needed to put something together for last month’s Maker Faire. A comically large, fully functional Arduino was the obvious choice. If you didn’t catch the demo last month, you can grab all the files over on Thingiverse.

Is that an atomic clock in your pocket or… oh, I see.

Here’s the world’s smallest atomic clock. It’s made for military hardware, so don’t expect this thing to show up at Sparkfun anytime soon; we can’t even fathom how much this thing actually costs. Still, it’ll be awesome when this technology trickles down to consumers in 10 or 20 years.

Converting a TRS-80 keyboard to USB

[Karl] is working on an awesome project – putting a Raspberry Pi inside an old TRS-80. The first part of the project – converting a TRS-80 keyboard to USB – is already complete. We can’t wait to see this build finished.

 A DIY Propeller dev board

Last week we complained about the dearth of builds using the Parallax Propeller. A few noble tinkerers answered our call and sent in a few awesome builds using this really unique micro. [Stefan]’s Propeller One is the latest, and looking at the schematics it should be possible to etch a single-sided board for this project. Awesome work and thanks for giving us a weekend project, [Stefan].

Controlling Robots With A TRS-80

[DJ Sures], mastermind behind the EZ-B Bluetooth Robot controller, sent in a really interesting build where he controls a robot with a 1983 TRS-80 computer.

The robot in question is [DJ Sures]’ adorable WALL-E we’ve seen before. WALL-E is controlled through a Bluetooth connection to a desktop PC with the EZ-Builder hardware and software package.

To get the Trash-80 talking to WALL-E, [Sures] connected a tiny Bluetooth module to the TX pin of the 6402 UART. It’s a very, very simple modification that adds a Bluetooth serial connection to one of the first notebook computers. After syncing the TRS-80 and WALL-E to the computer running EZ-Builder, it’s a piece of cake to make the robot respond to the clanging of a 30-year-old keyboard.

There’s a video of [DJ Sures] going over his build after the break with a wonderful demo of WALL-E freaking out to a little dubstep. Check that out after the break.

Continue reading “Controlling Robots With A TRS-80”

Giving An Old Atari Computer A Much Needed Upgrade

As a kid, [Boisy] cut his teeth on the TRS-80 Color Computer. It was a wonderful machine for its day, featuring a relatively powerful Motorola 6809 CPU. Although his CoCo was theoretically more powerful than its Commodore and Apple contemporaries, the graphics and sound capabilities of [Boisy]’s first love paled in comparison to his friends 6502-based machines. A little jealously and thirty years go a long way, because now [Boisy] is adding a 6809 microprocessor to the 6502-based machines Atari put out.

[Boisy]’s goal for his Liber809 project was simple: Put a 6809 CPU in an Atari XEGS and get NitrOS-9, the Unix-like OS for the TRS-80 CoCo running on his Frankenputer. After a few months of work, [Boisy] completed his goal and more so: the Liber809 also works on the Atari 1200XL.

To put [Boisy]’s work in perspective, it’s like he took a Macintosh from 1993 and made it run on an Intel 486. While that’s not a terribly accurate analogy, we hope our readers will understand the fortitude needed to make a computer run on a completely different processor.

After the break, you can check out a neat demo app written by [SLOR] from the AtariAge forums showcasing a 6809 running in a machine designed for a 6502. Awesome work for all involved

Continue reading “Giving An Old Atari Computer A Much Needed Upgrade”

Loading Programs Onto A TRS-80 Model 100

We’d guess that you don’t have a TRS-80 Model 100 computer sitting around. But we’ve heard that the decades-old hardware is built like a tank so if you search around you can probably get your hands on a working unit. The Model 100 boasted some nice features, one of which was a 300 baud modem allowing you to transfer data onto the device. [MS3FGX] wanted to give it a try but had to do some work to get the Model 100 to communicate with modern hardware.

This could have been a much more involved process, but since the Model 100’s modem uses common communications standards it’s really just a matter of hooking it up and choosing the right COM port settings on a computer. In this example a Linux box is used with the program Minicom. It is configured to communicate at 300 baud 8N1 (8 data bits, no parity bit, and one stop bit).

With software in place you’ll need to make your own cable. [MS3FGX] does this using a DB-25 connector for the Model 100 side, and a DB-9 connector for the serial port on the Linux box. He’s got a pin-out for the cable on the second page of his guide. It sounds like it should be no problem to use a USB-serial converter if you don’t have a serial port.

Once everything is in place you’ll be able to transfer BASIC programs from your computer to the Model 100.

Tandy Color Computer (CoCo3) Color Video Playback

[John W. Linville] wrote a digital video player for the Tandy Color Computer (aka TRS-80). The decades-old hardware performs quite well considering the limited resource he had to work with. This is the second iteration of his player, and can be seen after the break playing a promo video for CoCoFEST 2011 where he’ll show it off in person.

In the most recent thread post (at the time of writing) [John] shares the methods used to get this running. FFMPEG is used on a modern computer to process the source video by separating the audio into an 8-bit 11040Hz file, and it generates several PPM files with the proper video frame rate. ImageMagick takes it from there to convert the PPM files to a bitmap format. It also processes each frame for differential changes, reducing the size to fall within the available bandwidth. They are then interleaved with the audio to produce the final format. Video is 128×192 with rectangular pixels. [John’s] already used it to watch such classics as War Games on the antiquated hardware.

Continue reading “Tandy Color Computer (CoCo3) Color Video Playback”

Making Punch Card Programming A Snap

About thirty years ago [H. P. Friedrichs] pulled off a hack that greatly improved the process of programming with punch cards. At the time, his school had just two IBM 029 keypunch machines. One of them is shown in the upper right and it uses a keyboard to choose which parts of each card should be punched out. This was time-consuming, and one misplaced keystroke could ruin the card that you were working on. Since you had to sit at the machine and type in your source code these machines were almost always in use.

But wait, the school acquired a dozen of the TRS-80 computers seen in the lower left. They were meant to be used when teaching BASIC, but [HPF] hatched a plan to put them to task for punch card generation. He built his own interface hardware that connected to the expansion port of the new hardware. Using his custom interface a student could create a virtual card deck that could be rearranged and revised to correct mistakes in the source code. The hardware then allows the virtual deck to be dumped in to the punching machine. This broke the bottleneck caused by students sitting at the punch card terminal.

We think that [HPF] sent in this project after seeing the antiquated hardware from that 1970’s calculator. These hacks of yore are a blast to revisit so don’t be afraid to tip us off if you know of a juicy one.