Smallest Discrete Transistor 555 Timer

May 11, 2021 by 28 Comments

Over at Tiny Transistor labs, [Robo] took it upon himself to reproduce the classic 555 timer in discrete transistor form. For bonus points, he also managed to put it in a package that’s the same basic size, pin compatible with, and a plug-in replacement for the original. The first task was deciding which 555 circuit to implement. He examined a handful of different implementations — and by examined, we mean dissected them and studied the die circuitry under a microscope. In the end, he went with Hans Camenzind’s original circuit, both as a tribute and because it used the fewest transistors — a point which helped manage the final size, which is only a little bit bigger than the IC!

Speaking of sizes, have you ever soldered an EIA 01005 resistor? We agree with [mbedded.ninja] who wrote on a post about standard chip resistor sizes, the 01005 is a “ridiculously small chip package that can barely be seen by the naked eye.”  It is 16 thou x 8 thou (0.4 mm x 0.2 mm) in size, and despite its name and placement in the Imperial series, it is not half the size of an 0201. The transistors are your standard 2N3904 / 2N3906, but purchased in a not-so-standard DFN (Dual Flat Pack, No Leads). We might think a 1.0 x 0.6 mm component as small, but compared to its neighboring resistors in this circuit, it’s huge.

[Robo] has done this kind of project before, most recently making a discrete recreation of of the classic 741 op-amp. We covered a similar, but larger, discrete 555 timer project back in 2011. If you want to go really big-scale with your own reproduction project, check out the MOnSter 6502 from five years ago for further inspiration. Thanks to [Lucas] for the tip.

Sinclair BASIC For Today

May 10, 2021 by 29 Comments

If you are of a certain age, your first exposure to computer programming was probably BASIC. For a few years, there were few cheaper ways to program in BASIC than the Sinclair ZX series of computers. If you long for those days, you might find the 1980-something variant of BASIC a little limiting. Or you could use SpecBasic from [Paul Dunn].

SpecBasic is apparently reasonably compatible with the Spectrum, but lets you use your better hardware. For example, instead of a 256×192 8-color screen, SpecBas accommodates larger screens and up to 256 colors. However, that does lead to certain incompatibilities that you can read about in the project’s README file.

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The Laser Power Record Has Been Broken

May 10, 2021 by 46 Comments

Lasers do all sorts of interesting things and — as with so many things — more is better. Korean scientists announced recently they’ve created the most powerful laser beam. 1023 watts per square centimeter, to be exact. It turns out that 1022 Watts/cm2 may not be commonplace, but has been done many times already at several facilities, including the CoReLS petawatt (PW) laser used by the researchers.

Just as improving a radio transmitter often involves antenna work instead of actual power increases, this laser setup uses an improved focus mechanism to get more energy in a 1.1 micron spot. As you might expect, doing this requires some pretty sophisticated optics.

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Four Servo Fingers Play Simon Better Than You Ever Could

May 10, 2021 by 10 Comments

Remember Simon? We sure do. Simon — as in “Simon says…” — from the leading edge of electronic games in the 1970s, which used four buttons, colored lights, and simple tones as the basis for a memory game. Players had to remember the specific sequence of lights and replay the pattern in order to advance to the next round. It was surprisingly addictive, at least for the era.

For those who never quite got into the Simon groove, fear not — the classic game has now been fully automated. While there were plenty of approaches that could have taken to interfacing to the game, [ido roseman] went with the obvious — and best, in our opinion — technique and simulated a human player’s finger presses with servo-controlled arms. Each arm carries a light-dependent resistor that registers the light coming from the key it’s poised above; the sequence of lights is sensed and recorded by an Arduino, which then drives the servo fingers’ replay attack. The fingers aren’t exactly snappy in their response, which might cause problems — if we recall correctly, Simon is somewhat picky about the speed with which the keys are pressed, at least at higher levels of play.

On the whole, we really like this one, not least for the nostalgia factor. We’ve had a lot of recreations of Simon over the years, including a Dance Dance Revolution version, but few attempts to automate it. And a crazy idea: wouldn’t it be fun to replace the replay attack with a machine learning system that figures out how to play Simon by randomly pressing keys and observing the results?

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Tetris For Game Boy Gets Online Multiplayer

May 10, 2021 by 4 Comments

Released in 1989, the Game Boy version of Tetris is notable for being the first game to support multiplayer via the so-called “Game Link Cable” accessory. So it’s fitting that, 32 years later, that same game is now playable with others over the Internet thanks to an open source USB adapter from [stacksmashing].

As explained in the video below, the adapter is essentially just a Raspberry Pi Pico paired with some level shifters so that it can talk to the Game Boy’s link port. That said, the custom PCB does implement some very clever edge connectors that let you plug it right into the Link Cable for the original “brick” Game Boy as well as the later Color and Advance variants. This keeps you from having to cut up a Link Cable just to get a male end, which is what [stacksmashing] had to do during the prototyping phase.

The DIY breadboard approach works as well.

Of course, the hardware is only one half of the equation. There’s also an open source software stack which includes a Python server and WebUSB frontend that handles communicating with the Game Boy and connecting players. While the original game only supported a two person head-to-head mode, the relatively simplistic nature of the multiplayer gameplay allowed [stacksmashing] to expand that to an arbitrary number of players with his code. The core rules haven’t changed, and each client Game Boy still thinks it’s in a two player match, but the web interface will show the progress of other players and who ends up on top at the end.

To be clear, this isn’t some transparent Link Cable to TCP/IP solution. While something like that could potentially be possible with the hardware, as of right now, the software [stacksmashing] has put together only works for Tetris. So if you want to battle Pokemon over the net, you’ll have to do your own reverse engineering (or at least wait for somebody else to inevitably do it).

The Link Cable port on the Game Boy, especially on the later versions of the hardware, is a surprisingly versatile interface capable of much more than just multiplayer gaming. While we’re certainly keen to see [stacksmashing] develop this project farther, we’re equally excited to see the non-gaming applications of such an easy to use computer interface for the iconic handheld.

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TrueTape64 Is A PC Interface For Your C64 Datasette

May 10, 2021 by 32 Comments

Back in the distant past of the 1980s, software was distributed on audio tape. Ones and zeroes were encoded as tones of different frequencies, and tapes were decoded by specialised hardware which could then spit out raw digital data to an attached computer. While software methods now exist to simply record audio from old tapes and turn them into data, [Francesco] wanted to do it the hardware way, and built a PC interface for his Commodore 64 Datasette.

The TrueTape64, as it has been named, is built around an Atmel ATTiny2313 microcontroller. This interfaces with the original Datasette hardware which takes care of reading the analog tape output and turning it into digital data. From there, the microcontroller communicates with an FTDI232 serial-to-USB adapter to get the data into a modern PC, where it’s compiled into a TAP image file via some Python magic.

It’s a barebones build, which goes so far as to run the Datasette’s motor off the USB power supply via a boost converter; those facing issues with the tape mechanism might do well to look there first. However, it does work, and a done job is a good job at the end of the day. We’ve seen similar hacks before, too – it’s great to see the community keeping cassette software alive!

The ARMv9 ISA, And What It Can Do For You

May 10, 2021 by 38 Comments

The number of distinct ARM Instruction Set Architectures (ISA) versions has slowly increased, with Arm adding a new version every few years. The oldest ISA version in common use today is ARMv6, with the ARMv6 ISA (ARM11) found in the original Raspberry Pi SBC and Raspberry Pi Zero (BCM2835). The ARMv6 ISA was introduced in 2002, followed by ARMv7 in 2005 (start of Cortex-A series) and ARMv8 in 2011. The latter was notable for adding 64-bit support.

With ARMv7 being the first of the Cortex cores, and ARMv8 adding 64-bit support in the form of AArch64, what notable features does ARMv9 bring to the table? As announced earlier this year, ARMv9’s focus appears to be on adding a whole host of features that should improve vector processing (vector extensions, or SVE) as well as digital signal processing (DSP) and security, with its Confidential Compute Architecture (CCA).

In addition to this, ARMv9 also includes all of the features that were added with ARMv8.1, v8.2, v8.3 and so on. In essence, this makes an ARMv9-based processor theoretically capable of going toe-to-toe with the best that Intel and AMD have to offer.

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