Single Board Computer thoughts and Amiga stuff

The Raspberry Pi was meant encourage more young people to get into computer science. There was a fear that the black box nature of modern phones and tablets would leave users computer illiterate, unable to drive the industry down the line. Back in the '80s, Britain (and also countries where the MSX and C64 instead were popular) went through a home micro evolution with the ZX Spectrum, BBC Micro and Acorn Archimedes shining brightly. BASIC computers were relatively cheap but required a very hands on approach and interest. The RPi was meant to bring that back, and as I understand it, initially booted into Python (instead of BASIC), and was supposed to come with a keyboard case of some sort. Ultimately they went for a Linux OS and naked PCB.

It sold well, but did it tackle the literacy problem? I don't know... when it comes to understanding computers and electronics I don't think it's done well using Linux which has many layers of mystery stuff, and then there are the tiny SMD components. Honestly, I feel like BASIC is still unsurpassed when it comes to learning about programming logic, bits, bytes, beeps and boops. BASIC might be a high level languange, but on older systems it scales well into low level stuff. My ideal learning platform would probably use a C-BASIC hybrid (like BlitzMax), compiled for speed, running on a lightweight custom OS... maybe something like my Microchip Valkyrie.

I didn't have as much fun with my Raspberry Pi as I did with the Arduino UNO. Like most people who bought these boards I initially just wanted something to fool around with, so in that regard I think a comparison between the two is warranted. A lot of single board computers feel like they are just slow regular but slow computers, desperately struggling to be a full modern computer capable of doing full video / browsing / emulation. The Arduino is stripped down and was easier to get started with right away and the components can be handled by big clumsy fingers. I think the C syntax is full of superfluous garbage though. Still, it didn't take me long to get an Amiga mouse wired up to some pins. The sudden understanding of how things work is very empowering. Video.

My overclocked-for-no-particular-reason Raspberry Pi running Raspbian. I didn't like Scratch, Python or C+OpenGL. RiscOS was snappy but unfortunately doing graphics is rather difficult using the included BASIC languages (the indexed screen modes are faked, I discovered). The two USB ports and lack of hot-swapping caused me some trouble (I don't have a hub). The SD card would get bent in the holder and developed contact issues. They use the smaller cards now.

Winner of the ORAC lookalike contest is.... RPi3!


I made this concept for a bitmap-graphics (blitting) oriented single board computer. Maybe around 200MIPS, enough for immediate mode graphics. It would boot from a ROM, similar to the Amiga Kickstart, into a Workbench-like OS. Mid '90s specs overall.

HitBit Amiga

A design inspired by the HitBit F1XD MSX by Sony, the Amiga 500, Acorn Archimedes and other computers with colored keys. This would be just a USB keyboard + case. At the top is space for the SBC, PSU and peripherals (internal Loopy sticky printer???). This solution is scalable (economically) because people can get individual components and do their own thing inside. Over the function key row there are two sliders, maybe for SysFan, Overclock... or Pong.

Logo mockup

Bananodore Fruitfly logo design. Obviously a play on the Apple and Commodore logo. Fruitfly translates to Bananfluga in Swedish. They are a simple yet complex little thing which can be experimented on in a quest for knowledge.

OS mockup screen

Another OS mockup, inspired by System 7. 512x384 in 16 colors, though the OS would probably run in 256 color mode as I'm not keen on 4-bit packed pixel. Certain programs could reserve a chunk of the palette (e.g. a block of 32 colors). Desktop BG can be an image, a tile map or flat color. Editing the look of the OS could be fun for many, if given easy to use built-in editors. Bitmap font editors are fun too.

Something old, something new, something borrowed, something blue...

There are many SBCs without character. When they all come with Linux or even Windows, the only difference is power, which makes some boards slower than others, and all slower than a full computer. It sort of kills the whole thing for me. Of course, making a custom OS from scratch is madness from a usability/product PoV, but to a tinkerer and scratch builder it could be the main appeal. I guess what's really missing is a fun, general purpose bitmap oriented graphics chip? I've seen a few... which were not particularly fun to be honest.

I may have mentioned this elsewhere, but there are a few pillars which make a (retro) computer/console design work for me: 1> Good case design. It's expensive and difficult so no one really does this. 2> Hardware identity. Graphics and sound make the most impact, but the general system architecture can have an appeal too (clean, knowable). 3> Software identity. Custom OS, useful programs and a good game or two. 4> Brand momentum. Though, perhaps it is more likely that, if a famous name is used, someone's hitchin' a ride >_<.

In the 1980s, home computers were computers at home, a fantastic notion. Some were marketed towards people who wanted to "learn about the computers", and this influenced their design on every level. They were made to be understood and came with carefully crafted manuals. Likely, much of this was down to necessity - the developers certainly had no network or extra clockcycles to leverage against the user (*cough Windows 10 cough*). Now the demands of the user are so high, and the manufacturers so many that it's impossible to make a knowable machine regardless. But, I wonder what we could do if we tried to make a knowable machine with modern-ish hardware.

A 256 color mode is very clean to deal with I think. Dipping below does increase complexity a bit, but it adds graphical identity, an area where this hypothetical system needs to immidiately stand out. In doing a fully custom system, there's also an opportunity to turn a back on much of the legacy crap which modern systems have to deal with. A fresh start, even if I'm perhaps derivative/traditionalist in terms of desktop appearance in my mockups around here...

The OS and architecture should be relatively easy to understand. The memory is bytes and bytes can be pixels which can be easily shuffled around. The system is powerful enough for the user/programmer to be a bit sloppy (because s/he might be a beginner). Optimizations due to constraints tend to complicate things. A compiled form of C-BASIC hybrid would be the most accessible. It can be pretty close to the hardware, yet simple, as long as the hardware is simple. I'm thinking about how you could POKE around in the memory in the C64.

The OS only needs to do the basic things, so no distractions like trying to get video formats, flash player, cloud stuff or an "app store" to work. The command line interface can be improved by the inclusion of clearly named commands, helpful manual pages and error messages (which is really trivial to do, but not done because the people who write those things do it for people who already understand the systems). When you start up CLI, it shouldn't be a bloody for-experts black-box. How about showing the most common, useful commands, how to get help, etc? Graaar!


Sony HitBit MSX3 concept by Arne

Mirror, mirror on the wall, who's the fairest of them all? Oh, I'm sorry Amiga, it's not you, it's the Sony HitBit F1XD and 101/202. Now COMBINE and reveal your ultimate form!

ZX Spectrum

Viva la resistance!

Compact single board implementation of the original ZX Spectrum... I don't think I missed anything.

Notice: The ZX Spectrum project is = NOW ON = a separate page due to sudden GROWTH.

CPC bonus

Quick redesign of this brick/plank.




My iMac broke after 6 years. Shopping for a new one, I found that there's no good mid range box (pizza/tower), so I drew something. It's the size of a 2.5 Mac Minis standing on the side.

Apple Macintosh Light (Cube)

Apple Macintosh LC but actually a modern office computer. I think... plastic cases like these have worse thermals so I'd put an aluminium heat sink on the back, like on my bench power supply. Silence is one of the things I like about macs... they're noticeably more silent than my silent-parts PC build actually.

( GE5P is a very nice robot design that Playmobil should bring back.)

Quick rear shot the Apple Macintosh LC³ It's maybe 16-17cm which is smaller than the Mac Mini, which means daughter boards to fit everything, and a drive bay, but modularity/repairability/upgradability was the wish all along. Charcoal/"space gray" metal backplate. And yes, that is a muscle-car style heat sink sticking out. Such a thing is inherently justified.

Another cube. Mixing styles from different Apple eras.

Apple Pi (apple silicon idea)

The Π1 (Apple Pi 1) could be a gateway product for people wanting to try MacOS. Full desktop, but reduced software suite and core count. A lot of SBCs are a bit of a hodgepodge and still struggle with basic desktop stuff, but I don't think the tailored apple silicon would. Though, as SBC hardware improves people just expect more and more from it, and video reviews tend to be overly focused on video editing because that's something reviewers do (but normal people don't).

Ryzen Pi

Another take on my Jupiter Ace compact keyboard redesign. Here I moved the Editing & Navigation keys to the left side, so it can be done while the right hand is on the mouse. On a normal keyboard, Copy-Paste, BS/Del, Arrows are too spread out. It's also useful to be able to modify the arrow keys for word and document stepping, which is solved here with the blue and orange modifier keys. Additionally, Shift is used for text selection as normal. Of course, these type of layouts work poorly in hectic games which doesn't allow rebinds or use a lot of quick inventory/group keys. My MNOP layout (here a left-handed compact variant) is not ideal but has a decent heatmap and reinforces the alphabet structure. QWERTY being established is rather unfortunate I think. DVORAK is alright. 0 & 1 are much more common numbers and those are not so accessible in most layouts, and a linear row can't one-handed without wrist movement. A numpad has a fair amount of hover movement and they're awkward to use with my off-hand so I never do. I have non-compact variants of this layout on my A770 and Famicube pages.

Letter freq. My MNOP block is actually 2-3 keys less wide than typical QWERTY, making shift and enter less of a stretch.

WIP. Expanded version which retains the compact block in case users prefer not moving hands much and actually learn the layout. I've added a number block above which can be handled one or two handed (and matched the layout somewhat in the block below). It's for number entry, CSV, arrays, and some currency stuff (maybe = can be used as enter in a calculator?). I felt like '"()[] also needed dedicated keys here. The Alts below are used as shift keys. The Function key block might be a bit precarious as it's vertical with squished keys. 16+24+46 keys.

I kind of like this layout the most out of the one's I've made up until Dec 2020... though I have yet to try it with this particular compact bottom row and layer layout. Here are some of the characters I'd like to cover, mostly from the ISO-8859 tables (my Famicube variant of this layout supports Japanese too).

Amiga / Windows
0123456789    =+-/*^<>±÷ו

,.:;!?&·~–—_…|¦\  (interpunct, tilde, en dash, em dash)
#¢€£¤$¥  ()[]{}

SP NBSP SHY tab DEL  (shy is soft hyphen)

'"‘’“”‚„‹›«»¡¿  (quote stuff)
`´ˆ˜¯¨¸ (loose diacritics, needs /|- strike-thru lines too )

½ ¼ ¾  ¹²³ªº  °%‰¬  §¶†‡  ™©®@  (where's 1/3?)

ßÞþ     µ  ƒ  œŒæÆ  Øø


àáâãäå  ç  èéêë  ìíîï  ð  ñ
òóôõö   š  ùúûü  ýÿ    ž

Greek / Math / Electronics / Smileys
≈ (approximate equal)


I forgot why I doodled these things.


A What-If. Discovered long after making this that IDR actually did make TOS for the Atari. *chuckle*

GUI mockup.

A modern motherboard form factor for vintage keyboard computer cases.

Arne's flippable USB

USB could've been made flippable without any extra cost on the device side by just adding flipped contacts on the host/motherboard side. A few cents extra cost there doesn't matter. The reason why they didn't make it flippable was apparently because they thought it would mean adding extra wires in device cables... which... is a pretty poor solution to think of out of everything that could have been done.

I made the pins thinner so new ones can be added between. Stacking 2+ female connectors is harder with my solution here unless there is a wire merge solution in the housing rather than on MoBo.


If VGA/RGB used the HDMI/DisplayPort connector type. From what I understand, the analog video signals experience crosstalk/capacitance so the wires were each twisted with a ground wire in the cable and it perhaps easier back in the day to wire them each to a pin, so VGA has 15. I'm just guessing here, but maybe with digital signals this crosstalk is less of an issue as the noise/artifacting is too small to flip HIGH/LOW (a bit).


Small, hard-shelled shutterless floppies in paper pockets.

I was thinking a monochrome environment for this one. Featured is the MSX font in 6-wide mode on a widescreen display. OS is a branch of CP/M, now open source? Thinking about it, it should be possible to tell passive and active commands tell apart so you know whether you're doing something or viewing something safely. Also, I think I prefer full names, like "Info Memory", "List FD1: filter *.txt*.doc", "Make Folder SuperProjects", or "Open TextEd".

This way you can't accidentally poop things up by typing something cryptic like "fddel". Perhaps adding "Just" before a dangerous command does it without asking ("Just Delete Stuff.txt"). Normally, you get a verification of what will be done (i.e. you can tell whether your parameters made sense). Could be shorthand versions too, where e.g. Open = O, etc. Could also be keyboard shortcuts (printed on keys) for quick-typing common things.



Doh! It should've been GEO-DOS. Graphic Environment ~Ooohh! - Disk Operating System.

Thing on a Spring stuff sprung forth.


Rainbow power at your fingertips.

Atom-1 LPC

Oh, man, what a blast from the past, the ATOM-1! I used to have to shuttle to the moonbase to fix these in the 2270's .

Packets back in time

Travelling back in time with ADSL technology.

RPi case

With internal port extension hub (with IO shield, maybe video signal adapters?), speakers, power brick. Inspired by the 2600 and Intellivision.

RPi troubles

By the way, here's one way to solve the red power light trouble on a Raspberry Pi. Some people have went out and bought new SD cards, thinking the old ones went sour, but I think the problem is that they bend/bow in the holder after a while. Adjusting the springy contacts didn't work for me.

I bought a couple of SD card sockets, but could not get this bodge to work. I had some continuity issues requiring track cutting and bodging at first but maybe the remaining problem is inconsistent wire length or capacitance or EMI.

I considered soldering directly onto the SD card pads... Here's the chip side of a card I probably borked while experimenting with this project. Smaller IC is probably a disk controller. In the '80s, some disk controllers were as powerful as the computer itself. Even SIM cards have small computers in them now, with memory, storage and encryption features used for identification.

Brainfart. Afaik, SD card write protect sliders just bump a leaf switch in the socket, and it's up to the computer to respect that. Floppy drives probably used a light sensor for that hole in the diskette and afaik on the Amiga a virus could not write to a protected disk by circumventing anything on the software side.

It's not really "creditcard-sized", is it? I don't have 1/2 square metre of desk space free so I never use my RPis. So much stuff to plug in for just a quick go.

At first this felt like a fun idea, but it misses the point I think. First, it would be expensive and the RPi is cheap. You'd have an underpowered computer in neat box. Second, there's not enough free brackets on the back and the whole idea of brackets is being able to add stuff. Front panel mounting is a big "?". Needs to be dynamic so people can make their own front panels.

Really, I think the best form factor for a RPi would be something along the lines of the Amiga 600 keyboard case (maybe using brackets on the back). Easy to just plop it onto the desk. Built in analog mouse-joystick/nub, so just power and screen to plug in.

Maybe the LEDs could use a buffer using follow mode OpAmps, in case the user hooks up other experiments to the GPIO. I don't really know much about this but saw a similar setup on the UNO rev 3 schematic (pin 13 onboard LED), thought it was interesting. Probably best to not mount front panel LEDs on a board, but have the driver circuitry on the MoBo instead. LED holders should be enough.

Also drew some random logo and sticker designs. I draw along the edges of the paper to prevent smudging. I remember seeing Trypticon and Scorponox in toy catalogues as a kid but I never got into action figures. Quite liked the idea of mini robots having a base. The G1 transformation articulations were quite cheap and unexciting. Tangent!

Rasbunny and Mekapi mascots. And Helipi?

ASUS Tinker Board logo edit. Roger Hargreaves or [o_o] style. Anyways, the Tinker Boards are nice to look at. TB2 even has a metal barrel jack - none of that micro USB nonsense.


Yeah I have one of these. Bought some 6mm silicon/rubber feet to put on the keys to make it usable (still in mail). Playing linux console here (apt-gets and screen calibration). The C.H.I.P. SBC in the Pocket runs a different OS and afaik has to be reflashed to be used with a TV. The desktop OS looks nicer than the RPi's, on pictures at least, but I haven't tried it.

Feet arrived & being tested. Works great for typing, but in games there's a fair bit of sideways stress on the "D-pad". Case design for this is a bit peculiar. Wish they had used screws instead of tabs. Price / assembly considerations probably.

PrBoom (Doom). I was able to hot-plug in a USB keyboard with a hub, and then plug in a mouse, then set it up for WASD + mouselook in game options. I very much prefer Quake 1 over Doom though.

I have never drawn a laptop until this. I have strong opinions on laptop design but the market offerings show that I must be wrong about pretty much everything. Inspired by Let's Note and keyboard blatantly snagged from Inspiron. White is easier to see. I don't like LED keyboards.

This is geared towards the tinker-heads and privacy aware (maybe even Stallmanites), as suggested by some of the features (or removal thereof). The ASUS logo would end up upside down when opened but oh-well.

Actually I think the lid might be flippable (symmetrical). I had some idea that it could be swapped out and come in various colours. And an upside down logo tells an onlooker that... "This is not for you, it's for me to admire when I have the lid closed".

I forgot a DE-9 serial communication port for hardware projects! Put an RS232 interface on your Arduino boards and strut around the maker-space like a real kool boi.

Sony Camera Boy, loosely based on the Mavica. Had cameras been as cheap as they are now, but in 1990, this would've been about 50 quid, but probably 0.1MP, using a simpler LCD display (actual price range then: 500-20000). Digital cameras arrived in the early '90s and some stored images in DRAM, so if the battery ran out before transfer the images were lost. The Mavicas came later ('97) and I think their floppy drive had some kind of speed writing mode. Depending on compression I'm guessing about 5-20 640x480 images could fit on a regular MF2HD, but Sony may have used a different storage format and were also responsible for making new types of floppies before the format sadly perished. It was useful in the sense that you could isolate small individual projects on air-gapped, labeled and very cheap media (1/10th of an SD card).

Actual SBC stuff again

Raspberry pi 1 socket adapter

The SD card socket on the RPi1 was kinda crap. Cards would bend and lose contact without a metal enclosure. Mine became unusable. I found this little adapter that kinda works, but it's a bit tight and eventually cracked the plastic socket. The extra height makes fitting the board in the case harder.

Raspberry pi 1 fan

I once ordered a few smallish fans for another now forgotten project. Decided to plop one on the old RPi1, which meant drilling a hole in the seemingly (but not so) brittle clear case. As it turned out I had also ordered a hole drill thing by mistake and it happened to be the exact right diameter. The fan is 12V brushless, which means it runs slower on 5V, which is fine for both cooling and sound level. I hear brushless motors can have integrated flyback diodes but I'm not sure about my cheap fan here, so I built a little circuit with a Schottky, a 22R for limiting, and 22uF+224 for maybe some filtering/decoupling. I left the yellow speed report wire unconnected. The fan+circuit draws 40mA in this configuration.

This RPi1 (overclocked to 1Ghz) will run DevilutionX (arm port of Diablo 1) quite okay at higher rez than the original (software upscale disabled). Looking at benchmarks, it seems the Raspberry Pi 1 (2012) is about on par with a 450Mhz Pentium III (1999) in Whetstones, floats, but since Arm is RISC it differs a bit. Half speed at math like Cos, Sqr, then 2x speed at fixed point & assignments, then 16x(!) at if-then-else. Wikipedia equated it more to a 300MHz PII. Unsure how the GPU compares as it's probably has different modern features (better video stuff). Wikipedia mentions the XBox (2001). GeForce had just arrived in 1999.

Earlier I put a similar circuit on my RPi3 for the smaller "RPi fan". Since it's a 5V thing it goes fast & buzzy without some limiting resistors. I looked at it with my scope but didn't see significant noise so I guess it has flyback diodes inside.


I've had my RPi1 & 3 sitting unused most of the time, so I thought I'd find some task for them. Because I only had a cheap 2GB micro SD card free I decided to try RiscOS again. I got a boot error so I decided to try Amibian instead. It's a stripped down Linux thing that boots a version of the UAE Amiga emulator, though in my case it booted into a kernel panic. So, I bite the bullet and buy a new SD card, 8GB class 4. I think class 4 is perfectly okay because there's barely any stressful disk (write) access.

I write the images to card on my linux laptop (Ubuntu Mate). There are two ways. The Disk utility (GUI) using Restore Image iirc, or command line using...


... to list the drives. My SD card is listed as sdb. The numbers after are partitions but the images goes onto the whole card (no number). I think sdb stands for Storage Device B (as it's the second device on my particular system I guess). sda is my internal SSD. I go to the directory of my .img file using ls (list files) and cd (change directory), then...

sudo dd bs=4M if=amibian.img of=/dev/sdXXX/ conv=fsync

Where XXX is b in my case. It's a bit dangerous because if you accidentally set "of=" to a system harddrive it's toast. The process will take some time. Not sure if sudo is needed and I don't know what the stuff means. Hey linux is a really secure OS let's make it so needlessly complex that users will paste sudo stuff written by strangers on the internet. This is the year of the linux desktop!

Setting up Amibian requires some more prep. The instructions recommend using a FAT32 formatted USB stick for moving (ROM, ADF, HDF) files onto the SD card. I only had my old 16MB DELL stick free, and it's, well, too fat to fit along with other devices in the RPi3 ports... so I had to use an extension cable. Ended up with the usual RPi cable octopus and decided to do something about it.

Actual enclosure solution. Technically not an enclosure. But, I made a keyboard computer by velcroing the Pi onto the keyboard. And look at that cable management. Also, sent some nasty keys to the gulags. I could fit several games on that 16 meg DELL drive. For some reason the adf files have to be moved over to the SD card using Midnight Commander which is one of those ugly and barely usable MS-DOS-like file browser thingies. MS-DOS was a cancer we didn't stop in time so now we've got fullblown Windows 10.

Resolved problems

I wrote the <2GB image onto an 8GB card, meaning > the file system should/could be "expanded". I found the option for that off in a raspi-config submenu (Advanced settings). Unsure if it expanded after reboot though, I didn't look.

Sound goes over nasty HDMI when connected to a TV. I might use a monitor and external speakers so I went into raspi-config and set it to force use of 3.5mm jack. If using headphones the Amiga's channel separation is uncomfortable but there are mixing options in UAE. If using a speaker without volume controls, they're sort of easy to wire up on a breadboard, but one can also exit UAE and go into linux console...

amixer set PCM -- 75%

...worked for me.

I had undervoltage issues. The RPi3 uses <1A naked but a 2.5A supply is recommended if doing heavier stuff + peripherals plugged in. My RPi1 supply is 2A but it turns out the issue was with the extension cable I used. USB data cables are not really made for that kinda use and, length might play in too. USB micro plugs is terrible from a usability point of view, being fiddly, sharp and stuck'y, the latter being an issue when you have a switchless cable and things crash and you have to constantly yank, fiddle and flip. I would prefer a barrel jack because they're so sturdy easy to use... but tech always takes the terrible path when it comes to standards and somehow managed to even mess up something as potentially simple as barrel jacks. There could've been a beautiful system of diameter (V) and colour coding (A) *dreamy eyes*

The kickstart ROM entry field keeps going blank, I thought maybe because I only have 3.0 to use with the A500 which wants 1.3, but I think I just need to hit "Rescan Paths" to solve it. Having no ROM causes the Pi to crash when starting emulation, and then I have to yank that shitty fiddly micro USB cable. Wouldn't be surprised if the SMD jack tears off eventually. At least then I'm going to solder on a real sturdy proper barrel jack for real men.

Mouse speed only goes down to 0.25 (1/4) but it's still too fast for lowrez games like Utopia. I don't have a DPI setting on my current mouse either. Maybe the devs expected desktop resolutions. Might be able to set it lower by modifying the settings files manually.

UAE emulation is pretty good iirc, but here I noticed that some cracktros seem broken (broken gfx, no sound)...might be a kickstart issue. Some Amiga games which were ST ports ran at a pretty low frame rate.

Unsure if I'm feeling joystick lag and frame rate issues or not. I'd have to write a test thing in AMOS I suppose.

Can't find a floppy sound setting in this UAE version. It's quite essential to hear whether disks are loading/saving or if things guru'd.

No scanline filter? I don't mind the somewhat blurry scaling, as pixels were never crisp and supercrisp ones look... shrill / off.

Heatsink temperature (in case, without fan running) is 50 degrees C during play.

Thankfully my USB joypad worked right away and can even be used to navigate the UAE menus somewhat.

F12 is default key for going in and out of emulator. Exiting UAE brings you to linux console.

Paradroid 90, Amiga version, on LCD TV. It's more accessible for a beginner using a Trainer for "unlimited time" (prevents droid degradation) and then F3 in menu, turning off transfer game. Avoid Unlimited Energy (HP) though as it just removes all challenge.

I don't like this design but here it is.

Raspberry Pi 400 keyboard case was released (Halloween 2020). It's perhaps what the RPi should've been from the start... but then again I'm a bit of a keyboard computer nut. But it's a chiclet keyboard without an edge margin and I'm not really into that, though it does make sense to have a compact form factor, and it probably works well as a unit near the TV. The back and underside has some bevel and ventilation action that's a bit interesting than the top, but it's unfortunately unseen. I decided to draw my own version, seen above.

I used half-height keys (Logitech K120-based). It's really just a repurposed version of my many MNOP keyboards, but here I kept the QWERTY + Fn Numpad layout even though I'm not a fan of it. Lettering is from the official kb. Had to move ? and numpad / because of up-arrow. Squeezed in F11 & F12. Another Fn near arrows. Extra shift can be for layers shenanigans or Japanese (which might need extra shifts for han/dakuten). I'd go for an internal PSU (C7 cable?) in this to further minimize setup time... though it might introduce more heat. Finding a PSU + cable is one of the reason I avoid my RPis. Apparently the cooling in the 400 is quite okay but my case might have room for an optional mini fan. The RPi400 has a keyboard flex connector similar to that of old computers like the Acorn Electron, Speccy. One of the RPi's USB ports are missing because it's used by the KB internally. I might be tempted to put the keyboard controller on a separate PCB for the sake of modularity. The USB on the left side is for sticks, the ones on the back for Mouse & Joy. Big SD card on the right (mouse side) to imitate floppy drive. The GPIO header is pointing upward and could have a little dust hatch I suppose. Some people might not use it. On the RPi400 it's on the back, like a ZX/C64 cartridge edge connector. I guess having the GPIO on the left side (not mouse side) could also work. The A1200 had something there iirc. But, top would be nice for stuff like... little displays or trimpot modules which could just sit there. Also allows for doublechecking connections in proper light conditions when experimenting. I mean... the GPIO supposedly is for experimentation as it's an educational platform, so it's not like you just put extra RAM cartridge on there and forget. Also, if you have a tutorial pinout up on screen it helps to not have to flip the keyboard over and around.

A modified version of my famicube project keyboard, with arrow+edit keys above instead. Number area became righthanded and some of the math stuff is near too. Greek letters can be useful for electronics, math and emoji, but I really just added them because games often need inventory keys over "WASD". The Swedish alphabet has three more letters so I left space for those (or others) near enter. Diacritic deadkeys on number alts as usual.

Notice: AMiGA keyboard project is = NOW ON = a separate page due to sudden GROWTH.

I reconditioned a cheap mouse which had gotten the jitters (just gunk on the lens piece inside... though the sensor is kind of garbage to begin with). Shell finish was degraded and nasty. I polished it with steel wool, but it's hard to get an even finish. Patches usually appear when dry, BUT, a very light coat of hand crème gives it a nice even satin finish :O Usually the hand fats tend to serve the same function. It's probably similar to wetting a rock. The most common points of failure on mice are:

I've never seen a failed IC in any of the dozen mice I've fixed at some point. I've had to fix a few micro-switches but never the rotary encoder for the wheel... on cheap mice that's an off-the-shelf piece anyways.

Innards of another cheap mouse. The mouse wheel actually tilts onto a switch but it isn't noticeable due to the small angle. The axle can be pulled out of the rotary encoder. It's just a hexagonal connection. I suppose the internal contacts of the rotary encoder can wear or get gunked up, producing bad/stuck quadratures.

If you want to open your possibly mint game boxes without creasing the lid, stick in a cutlery knife and carefully rotate/twist it open, then shake shake shake out the contents.

I heard about a new RISV-V SBC called Picorio and imagined this form factor, putting the connectors mostly along one edge. Would be cool to have an SBC which boots into BASIC with easy GPIO manipulation and graphical plotting. The Color Maximite 2 does this. Competing with the RPi is kinda pointless, though I guess RISC-V has the appeal of being open. I'mm rooting for ya, RISC-V. Oh, I put a Composite and DIN VGA ports on this because HDMI is proprietary and can carry HDCP payloads.

Status LEDs can be too bright in a dark room. An LDR can be used as a dimmer. I experimented a bit and found some configurations that sort of works. The transistor somehow keeps the light levels more consistent as the LEDs blink.

Some other hardware pages

Amiga HDD - Amiga cleanup - Amiga pixels - SBC - A770 - Assorted - MSX - Acorn project - Amstrad project, etc. - ZX project - Assorted - Electronics Endeavour

Art by Arne Niklas Jansson