When Is A Typewriter A Printer? When It Has A Parallel Port

If you want to talk to a typewriter using something other than your fingers on the keys, you could do a lot worse than to pick up a specimen featuring a Centronics parallel port. That’s what happened to [mlupo], who came across an old Swintec 1146 CMP and decided to hack it into an art installation.

At the push of a giant, clicky button, the typewriter now spits out family stories. This is all thanks to an Adafruit KB2040 keyboard driver being used in a new, exciting way — as a printer driver.

More specifically, the CircuitPython program running on the KB2040 takes in a text file and then sends the data one character at a time until a newline is reached. At that point, the typewriter sends a busy signal and the characters are typed.

As soon as the typewriter is no longer occupied, the data stream picks back up until the next newline or until the file is completely typed out.

Once [mlupo] figured out enough of the parallel port protocol, they were able to build a custom breakout board with the KB2040, a female parallel port, and a row of LEDs for debugging that [mlupo] kept because they look cool.

The KB2040 sets the values high on a series of the parallel port’s data pins, along with the port’s STROBE pin, which pulls low when data is ready. During each STROBE cycle, the high and low pins are read by the Swintec as a binary character.

Of course, you can always use the power of Pi to build your own modern typewriter.

Thanks to [foamyguy] for the tip!

Raspberry Pi Changes HATs

Following on the heels of their Raspberry Pi 5 launch and some specifications for their RP1 all-in-one peripheral chip, the Raspberry Pi folks have now released an update to the HAT peripheral hardware specification reflecting the new model. Called the HAT+, it represents a major step forward with some significant changes.

Most visible will be changes to the mechanical specification, for while the original HAT specification was very rigid this new version is much looser. A HAT+ must only mate with the 40-pin connector, including the ID pins, and line up with only a single mounting hole compared to the four on the original. Electrically, a HAT+ must recognise the standby power state in which the 3.3-volt line is powered down while the 5-volt line remains active, while software-wise, there are changes to the content of the ID EEPROM including the ability to inform about stackable smaller HATs.

Continue reading “Raspberry Pi Changes HATs”

New Part Day: Flush-mount Touchscreen For Retro PC Build

I recently had the opportunity to purchase an early version of a new display, and it happened to be just the thing I needed to make a project work. That display is the Elecrow 11.6″ CrowVision touchscreen slated for release in 2024. Preorders are being accepted on Crowd Supply.

I had an idea for a retro-inspired PC build that was just waiting for a screen like this. I’ll talk about the display and what’s good about it, then showcase the build for which it was the missing piece. If you’ve got a project waiting for something similar, maybe this part will provide what you need or at least turn on some new ideas.

What Is It?

The CrowVision 11.6″ 1366 x 768 touchscreen has an HDMI input, USB output for touch data, and accepts 12 V DC. It’s made to interface easily with a Raspberry Pi or other SBC (single-board computer).

Personally I consider a display like this to be the minimum comfortable size for using desktop type applications in a windowed environment. Most displays in this space are smaller. But aside from that, what helps make it useful for embedding into a custom enclosure is the physical layout and design.

Since I was looking for the largest display that could be flush-mounted in an enclosure without a lot of extra space around the display’s sides, it was just what I needed. The integrated touchscreen is a nice bonus.

Continue reading “New Part Day: Flush-mount Touchscreen For Retro PC Build”

Raspberry Pi 5 Goes Under The X-ray

Most Hackaday readers will know to some extent what lies inside their computer, even if this is only at a block diagram level listing the peripherals. But what is physically on a modern computer board? [Jeff Geerling] has subjected a Raspberry Pi 5 to a medical imager, and shares with us the many layers of parts and PCB he found there. With a six-layer board and a heap of large BGA chips on it, there’s a lot to look at.

For readers who are used to working with printed circuit boards, it’s likely the techniques involved in the design will not be new. For us, the magic lies in the scale. The sheer number of interconnects on the board is impressive enough, but when it becomes possible to peer into the SoC package it becomes evident that there’s an internal PCB with some of the smallest vias we have ever seen. [Jeff] goes on to show us part by part around the board, on the way reminding us that some of the earliest Pi boards had to be reworked to replace Ethernet jacks without magnetics.

There’s a beauty to these ghostly images which might not be apparent to anyone who hasn’t stared obsessively at a PCB in a CAD package while it takes shape. The images show the work of the PCB designer’s art at a fine scale. We’d almost go as far as to suggest they be viewed as fine art instead of industrial design. Take a look, the video is below the break.

If this art is a bit big for you, then look at ASIC design – which takes things down to the microscopic level of the doped silicon structures within these amazing chips.

Continue reading “Raspberry Pi 5 Goes Under The X-ray”

Pico Makes A So-So Keyboard Neat-O

When someone gives you a crappy little toy keyboard, what can you do? Sadly plunk on the thing one note at a time? Well yes, but that’s not going to get you on Hackaday. Do what [Turi] did and give that thing a complete overhaul.

[Turi] threw away the original controller board, keeping only the keys, buttons, case, speaker, and a little bit of the original powder yellow enclosure. The Picophonica’s new brain is, you guessed it, a Raspberry Pi Pico. This enables [Turi] to use [Ryo Ishigaki]’s pico_synth_ex synthesizer and introduce MIDI out via USB-C.

The new engine does things that little keyboard could never have dreamed of originally, especially considering it wasn’t even polyphonic. Those fourteen white buttons now control things like sustain, cutoff, LFO rate, decay, and so on. Now it sounds great!

Be sure to check out the brief build video after the break. Excluding drums, the soundtrack was made entirely on the Picophonica.

Of course, Picos aren’t just good for musical keyboards. Use one to convert an old proprietary keyboard to PS/2, or create your own.

Continue reading “Pico Makes A So-So Keyboard Neat-O”

Metronome Flashes And Vibrates To The Beat

Annoying though they can be, if you play any kind of instrument, you will definitely benefit from using a metronome. While many of them thock or otherwise tock, the VRRVRR metronome from [Turi] works a little differently.

In addition to flashing LEDs, the VRRVRR contains a small vibrating motor. If you’re wondering about the name, it comes from the fact that it vibrates and makes a sort of vrr vrr sound. Need to be quiet? A small switch on the side shuts off the vibrations.

The 4×4 keypad really allowed [Turi] to cram in a bunch of features using both short and long press to do different things. On short press, the digits set the tempo. When not typing in a tempo, zero can be used to enter a tempo by tapping. The letters load preset tempos, and the +/- keys increase and decrease it.

Inside the basswood enclosure is a Raspberry Pi Pico, the vibration motor, and various other bits and bobs that make it go. There’s even an LED to indicate that it’s time to charge the lithium battery. If you want to build your own, head on over to GitHub, but be sure to take the brief VRRVRR tour after the break.

We don’t see too many metronomes around here, but we do have this nice teardown to offer you.

Continue reading “Metronome Flashes And Vibrates To The Beat”

Another OmniBot 2000 Upgrade

There were many toy robots back in the 80s that were — frankly — underwhelming by today’s standards. Back then, any old thing that rolled around with some blinking lights would impress, but the bar is higher today. Then again, some of the basic components won’t really change. You still need wheels, motors, batteries, and all that. But the computers we can bring to bear today are much better. Maybe that’s why so many people, including [mcvella], decide to give these venerable toys like the OmniBot 2000 a facelift or, maybe a better analogy, a brain transplant.

In this particular case, the brain in question is a Raspberry Pi. The robot will also sport new sensors, motor controllers, and a webcam. There is also a new battery pack in play. The project doesn’t cover working with the single powered gripper arm. The left arm isn’t motorized. There is also a cassette tape deck you could probably make do something interesting. Of course, with a Raspberry Pi, you get wireless control, and the project uses Viam to define and control the robot’s motion.

There is some retro cool factor to using a robot like Ominbot. However, we might be more tempted to just build our own. With a 3D printer, a laser cutter, and a few motors, you could make something that would be about equivalent or better with little effort.

We have seen OmniBot conversions before, particularly over on Hackaday.io. Maybe someone will convert one over to steam power.