Entrants List 2017/04

Listed below are the competitors joining us for the 2017/04 event:

Mark D. Overholser (aka MarkO)



To make this a project that actually can be completed in time, I am "attempting" a Multi-Player, Networked Text Adventure, with a Server running on a modern PC, and the Clients being the Apple ][, ( with the Uthernet II Card ) and the Tandy CoCo, ( with a Serial Port and a Lantronix UDS-10/100/1000 ).




www.vintage8bit.com/path TBA when I fix my broken site.

I will build a Tynemouth Systems Minstrel ZX80 Clone Issue 2 and design (and maybe build) an mechanical keyboard with Cherry MX style keys that can be used on the ZX80, ZX81 or or other matrix keyboard systems.


Sean McNamara


Me again for 2017/04, a "europlus Refurbapalooza Revisit".

A slow start, but achievement of a practical result and production of "WOzFest Labs Apple Astec Power Supply Unit AA11040B/C Electrolytic Capacitor ‘Spec & Check’ Sheet" -- nice!

Scott Lawrence



My plan for this RetroChallenge is to recreate pixel perfect versions of some of Andy Warhol's Amiga works, in their original  file formats, using an Amiga, and/or Amiga emulation.  I will be using Deluxe Paint and GraphiCraft as well as reference images to make the reproductions.

Many pieces have been released, but all of them are in non-amiga-native formats, usually PNG, JPEG or as screenshots in videos.  I want to reproduce them as IFF/ILBM in their original 320x200x32 color format.

It's a vast departure for me from previous RC's, doing arty stuff instead of hardware-ey stuff, but I've been wanting to do this for a long time now, and this feels like the best opportunity to do so!

Yes. the above JPEG is not good enough for me.  ;)

Good artists copy, great artists steal, and Retrochallenge competitors take the long way.  But, is this art or archaeology? Or some sort of living history? Dunno, but thanks for the read!

Jim Gerrie

(Twitter free)


Blog about my recent programming activities:
  • “Aerien” my 3rd entry for the Basic 10-liner programming competition
  • My updates to my Sokoban program
  • Doing the last 3 programs for the Microdeal 5 part text adventure series (Castle Dracula, Mansion, and Adventure in Jerusalem)
  • Port of C64 game Aerojam
  • Roulette and The Quest from Dick Smith VZ200
  • New game “Curse of the Undead”

WITHDRAWN -- but Jim, you've been so busy!

Tom Raidna




Using Altirra the Atari 400/800 emulator complete the following :
  1. complete the Dorsett Education program (cassette s/w with voice) on Statistics - 16 cassette files downloaded from archive.org and document at traidna@wordpress.com
  2. Write a statistics program in Kyan Pascal on Atari 800 (emulator) which will compute descriptive stats, Anderson-darling test for normality, one and two sample T-Tests, one and two proportion tests etc.
  3. create youtube videos on creating the statistics program, as there does not appear to be any for Kyan Pascal on Atari
  4. blog on the process at traidna.wordpress.com, update the kyanpascal.wordpress.com blog on creating programs
A somewhat intricately devised Retrochalleng entry, tied directly to Tom's eclectic educational and professional background. This brings together the Dorsett Educational tapes we have heard so much about from Keven Savetz, and a nearly lost Pascal compiler for 6502 machines (particularly for Atari 8-bits). Very exciting for us fans of the ANTIC podcast! The statistics part, well...it's probably not everyone's "thing". Still, it was cool for me to see the old Atair 8-bit put to work demonstrating real world mathematics, and the use of the old "learning language" Pascal definitely puts me in the retro mood. This is a top notch project.
Spencer Owen



Recently I picked up a whole load of kit from a company that had no use for it any more.  Roughly speaking it's a custom CP/M machine, a lot of Z80 single board computers, backplanes and a myriad of expansion PCBs.  There's also some Z80 In Circuit Emulators, keyboards, power supplies, empty rack and other yet unidentified items.

Throughout April I intend to sort through this.  Primary goal is to identify what everything is and catalogue it all with decent photographs. Getting down and dirty with some of the boards and identifying pinouts, chips used, dumping EPROM contents etc will also feature.  The CP/M machine looks like it needs some TLC, but hopefully I'll bring it back to life. The Z80 ICE's have got documentation with them (which if it isn't already available online means I'll scan it all to PDF), so I'd like to get them up and running, at least to find out if they will be of any use in the modern world.  Finding good homes for some of the kit is also a stretch goal.

Impressive attempt at getting excuses in early! But, I'm not really sure there are any points to be had for that... ;-) Those ICE machines sexy enough to make me want a Z80 project (as if I didn't want one already)! I was a bit jealous of those keyboards too -- they can be hard to find these days. Kinda lost me on the rack, but that's fine...thanks for some nice documentation of your month's activities!

Phillip Stevens



I have been working on modern Single Board Computer build with retro components over nearly a year. It therefore doesn't qualify for the Retro-challenge as it is a long term project. So the challenge entry is effectively a "sprint" within the overall project, to implement an IDE interface for the YAZ180.


The YAZ180 is a combination of the fastest Z80 processor available, running at 36.864MHz, together with 1970's components. Included in the build are the AMD Am9511A-1 APU, Lattice GAL devices, Intel 82C55, and a number of Texas Instruments TIL311s.

My intention is to receive the PCB with the designed IDE interface early in April, build up and test the new version of YAZ180 (which is in itself a challenge) and then, using a combination of the code from Paul and ChaN, read and write an IDE PATA drive with FAT32.


A very cool hardware and low-level software project! A series of misfortunes and small errors prevented a clear success, but Phillip persevered and even got a little help from another competitor to get things moving toward the end, plus some real success just a bit after the deadline -- very nice.

Frank Linde



My entry for RC 2017/04 will be a mingle-mangel of several things:

The Commodore PET 2001 turns 40 this year and I scored a defective one about a year ago on ebay. Some issues have been fixed already, but the system is still disassembled and has to be tested as a whole. I assume the PET would appreciate to be reanimated at its birthday.

The Video Graphics Array (VGA) turns 30 this year. Having a weakness for graphic extensions (see my RC 2015/7 entry) my main entry to RC 2017/04 will be a PET/CBM Color Graphics Extension sending pixels to a VGA display.

The Atmel AVR 8 bit architecture turns 20 this year. So I'll use this type of MCU for the graphics board.

Celebrating 40 years PET 2001 plus 30 years VGA plus 20 years AVR sum up to 90 years of Retrocomputing. That should comply with the RetroChallenge Rules quite easily.

Like so many projects, this one starts with a resusitation -- thankfully a successful one! With 8 days left in the challenge, work started on the PET AVR VGA display board. Shortly thereafter, the cycle counting started... Schematics come very late, but the breadboard wiring is very neat and tidy! The necessary firmware for the PET never quite got done, but there are some nice pics of some static VGA output -- PET lovers, stay tuned to see where Frank takes this long term!

Richard Loxley



"RetroMatic 2000"

I collect 1980s computers. But they are gathering dust in my loft, and I'd prefer they were being used.

My project is to build something that will make 1980s computers easier to use in the modern world:

(1) connect to an LCD monitor so you don't need an old telly;
(2) store files on a USB stick so you don't need mechanical disks, and can transfer files easily.

There are some products that already do some aspects of these, but no-one does an all-in-one box that can connect to an old computer and "it just works".

I'm making an all-in-one solution (working title "RetroMatic 2000"), in a retro case that befits my old computers :-)

I'll be testing it on my EACA Video Genie EG3008, and my Amstrad CPC 464 and 6128. But it should work with most computers of that era, and I hope to eventually use it with my BBC Micro and TI99/4a.

I've only just found out about the Retro Challenge but I've actually been planning this for a while! I spent March creating the design, and testing some technology that I'll use.

So for the challenge I'll start by blogging about my design process, and then carry on with the actual build, blogging as I go.

What a blog! Lots of details on the project, which involves building a box to convert video for modern displays and storage for modern devices -- a very practical retro computing project. Richard takes a non-nonsense approach, even hacking the "off the shelf" bits of the project to bend them completely to his will. In the process, he gives us a great view from the passenger seat as he engineers his way through every problem. Plenty of parts of his design are borrowed from other projects, but he gives credit and does a great job explaining how things work. This is seriously good stuff.

Towards the end Richard wondered if it was better to get something working and ugly or something non-working but pretty. For the record...we have a special preference for "weird and ugly" here at Retrochallenge, so long as things work. But there are no penalties for things that look good, and this one surely does.

Bob Kiley



I hope to completely set up a working Vic-20 system for my RetroChallenge. I have many pieces acquired over the years but have not actually set them up or used them for decades.  I have printers, floppy drives, modems, and boxes of stuff that I have no clue what might be in there.  I want to get them out, set them up, see what works or doesn't work and what it might take to get them going again. This is my first RetroChallenge so I will also learn how to blog and share this adventure.

Bob reacquainted himself with his considerable VIC-20 collection, including the requisite clean-ups and small repairs. A capacitor replacement attempted to defeat him, be he cleverly overcame that challenge along with a few other minor repairs. Then he acquired an SDIEC and started achiving his software, then he got his printer working, and got a new monitor, and...well, let's just say that Bob's retro disease is progressing along normal lines... :-)

Niels Moseley



If my HD63C09 CPUs that I bought from eBay arrive on time, I'm going to design and build a computer with it. I don't be surprised though if it pivots into something completely different.

Another good write-up, with a nice level of detail and yet still some enthusiasm and fun to read. Also a topic close to my heart, given that the CPU in question is closely associated with the Tandy Color Computer. Unfortunately, it sounds like the results at the end of the month were less than satisfactory. Let's blame King Willem-Alexanders's brithday for wasing too much debugging time!

Alan Garfield



I have an old industrial controller from AMX that has a Motorola 68000 I'd like to reverse engineer. It was last produced in 1994 and was used to control lights, audio/visual equipment, access control etc. It was saved from the trash over 10 years ago when a boardroom system was replaced with something newer. I figured it would be an interesting board to play with.

I plan to reverse engineer the board. It has two UARTs (one RS232, the other a proprietary serial bus which looks like poor mans RS485), an OKI clock/calendar, battery backed up RAM, a single LED and 8 DIP switches.

I'd like to get a ROM monitor running on it, and then progress to BASIC or a Forth interpreter. Ultimate goal is to have all the hardware working and produce a TTY Mandelbrot set.

Worst case, even just getting the single LED to blink via RS232 would make me happy.

Another nice write-up! This one hit close to home, as someone with a background in embedded systems software with an affinity for the Motorola 68k. The early bit about dumpster diving for PCBs called to me as well. A great description of reverse engineering bits of two different boards follows, including schematic creation and adventures in burning and erasing EPROMs and EEPROMs. It was great to read of Alan's final conquest of this Retrochallenge goals, even if they did come a bit late for the contest...

Matt London



My first laptop was a Victor V86P, which was an 10MHz XT compatible system. There's a little information out there these days, but really not all that much, especially on the technical side. For this Retrochallenge, I'm going to try and gather as much information about the Victor V86P laptop as possible and get it up on-line.  In no particular order:
  •    Setup somewhere to post (and organize) the technical information gather as part of this project
  •    Document as much as possible about the hardware of the V86P, including such things as chipset and pinout
  •    Dump the system BIOS
  •    Try and establish the pinout of the Expansion connector on the back (could be ISA)
  •    Try and establish the pinout of the Hard Disk controller daughterboard connectors - I expect this to be a subset of ISA signalling
  •    Gather and document as much information on the JVC 26-pin disk interface as possible - there's not much about this interface out there, other than it may well be a typical RLL interface with a few extra signals
  •    there's a pinout here. To this end, I have a cheap USB TTL logic analyser on order, and a breakout PCB being manufactured.
  •    Try to figure out the mystery pin on the PSU input and the battery charging arrangement

Still another nice write-up, with some great electrical engineering details in many of the posts. I have often wondered if old PCs and laptops will cross the chasm to full "retro" status. From the looks of this entry, at least some old PCs and laptops can be interesting enough to inspire such love -- great to see it as part of this very enjoyable engineering tale of power supplies, disk interfaces, and data sheets -- oh my!
Rob O'Donnell




OK. Time to try and do this again...

But maybe a smaller goal...  I might have a chance of completing it!

My rose-tinted-glasses old-tech website www.viewdata.org.uk has been a little dormant for a while. I've been re-building it slowly using wordpress, but need to build some custom plugins and software to cope with showing off files that no modern computer understands.  They don't even have mime-types!

Thus, the goal will be to :

Write a web-based viewdata browser, and associated server-side code, possibly using ajax, in order to access and browse the various 25+ year old viewdata databases I have available.

There is a faint chance I'll actually make the beta website live, if I get all of the code needed done!

An interesting project, seemingly perfect for Retrochallenge -- a bit of preservation mixed with a bit of learning a new programming language. Viewdata sounds like it would be the perfect format for viewing data...or is that teletext? Either way, sorting things out between PHP and Javascript seemed to be just getting in hand. Sadly, Rob lost his Dad partway through the event. Rob, please accept our sincere condolences. Please take a moment to visit the memorial to Rob's father, John O'Donnel.

Andy Collins



Please book me in for the first of this year's Retrochallenges.

I have no idea what I'll do this time around but it will be retro and something of a challenge.

Here we have a cool little project to add Compact Flash storage to a machine. The idea of using an RC2014 CPU card as the basis for a "plug in the CPU socket" add-on card is ingenious! Alas, the device only seems to work when tickled manually from the monitor (but not from normal assembled code). Still, a valiant effort with a nice write-up to entertain us.

Micheal H. McCabe



My project this time is called "Tapestore."  It's a small database containing large objects like operating systems, system images, video tapes, audio recordings, and photographs that are stored on a variety of media ranging from punch cards to 9-track tapes to various obsolete disk storage systems.  My goal is to put all this digital detritus into a form that can be stored and selectively retrieved on modern large-capacity hard drives but still be accessible to both archaic computer systems and modern emulators.

Vintage gear supported by this endeavor will include the Digital Equipment Corp. PDP-11, the Apple II+, Apple Macintosh, and Vintage PeeCee Type Equipment.  Work product will include source code, blog entries, and hopefully some video.

A nifty project around data preservation, involving a number of old media formats. Part way through I think the goal was "a version of YouTube circa 1984", but I'm not sure we really got there. There are some nice shots of "equipment pr0n", and bonus points for video of a 9-track tape driver in action... All in all, a nice effort!


(Twitter free)


My intended project is to attempt to resurrect my dying,possibly already dead, Acorn A5000.

A few years ago it suffered the all to frequent 'BIOS Battery' leak, which I thought I had caught in the nick of time. The machine limped on for a little while after that, not showing any obvious signs of longer term effects, but eventually stopped booting into the GUI all together. I've since, to my shame, left it for another year and now ended up with a machine that shows very little sign of life.

The challenge will be to attempt to save the machine over the next month. It could prove to be a very short story indeed or an epic tale of electronic heroics and adventure. I'm currently not sure which...

Resuscitation of an Acorn A5000, a good goal. A typical case of dealing with bad/leaky capacitors and batteries, along with good old fashioned cleaning in general. Add-in some attempts to repair lost PCB traces too. Construction of a CMOS/RTC chip replacement circuit still fell a bit short this time. But good luck, and thanks for the write-up!

Christopher Just



I'm picking up where I left off with last year's Retrochallenge, and doing more work on my Commodore 64 CRPG program. This time around I'm going to start with a conversation system and see where that takes me.

A continuation of an earlier Retrochallenge project, Christopher makes some more progress on his RPG for the C64. The cc65 compiler project went through some changes that required some refactoring, but apparently that was not a big deal other than a little time lost. Various features were added, with corresponing discussion in the blog. There is also some good discussion of what RPGs need and how to care for those needs in software. Some last minute "hack and slash" to the code added enough functionality for Christopher to create a simple quest and declare victory. It would be hard to ask for anyting more!




SIBO resurrection:

SIBO machines made by Psion are 16-bit multitasking machines, the first of which, the MC400, was released in 1989. I will resurrect one of these machines from dormancy and make sure I can continue to develop software for it in a modern environment.


Mark Sherman



I will be trying to build a computer around old, literally rusted, RCA 1802 COSMAC chips.

This one starts with a hack right out of the gate -- soldering the pin stumps of an RCA 1802 into a socket, to make the chip usable again! Not satisfied with that brute-force accomplishment, Mark goes on to prove that the chip was working by hardwiring it to fetch NOPs. He then goes on to build a full computer similar to (or inspired by) the COSMAC ELF that many of us have experienced first hand. Mark then goes on to very hansomely house the circuit into an old CD-ROM case, and then takes a victory lap by producing a demo video of the device in action. This seems like a great project, for sure!

Dana Bowen



My project will be a multiplayer game running on an emulated DEC PDP 11/70.

DID NOT FINISH, but it looks like some fun was still had in the process!

Matteo Trevisan



My new project is about ATARI world, i want to make an Operating System for Raspberry pi (all version) with Atari emulators and Atari games for linux so it's reverse engineering some old Atari consoles. I want to try to reproduce also in package paper a Raspberry pi b2 b3 Atari 2600. I hope you will like my project.

Another enthusiasitic entry from Matteo! It is great to see all the content he produces, and I surely hope he is having fun in the process. This time around Matteo displays his love for the Atari, while apparently embarcing every version of Atari emulation known to humankind... :-)

The popularity of the Raspberry Pi had led to a number of special-purpose Linux distros to run on the various Pi models. As cheap as the machines are, why not have specialized loads of otherwise general purpose operating systems to run on them? If that describes your thinking and you are an Atari fan, then check-out what Matteo has been doing!

Erik Piehl



TMS9900 CPU done in VHDL.

I did the TI-99/4A clone using an FPGA and TMS99105 CPU as my retrochallenge 2016/10 entry. That was a fun project with a successful result. Since then I have received requests from people in the community to do the full TI-99/4A for the MIST board. Well I don’t have a MIST, but if was able to implement a VHDL version of the CPU, then I would have the full TI done in VHDL, and anyone could do the MIST version. I have at least a dozen FPGA development boards already, so I could port the design to a few of those.

In the spirit of retrochallenge I am talking about a quick-and-dirty implementation of the CPU. While a sensible person would think about building blocks and design elements and what not, a quick-and-dirty implementation would be goal oriented: the first task is not to build building blocks, but the build something that can fetch data from memory, do a TMS9900 style reset and execute one instruction: a NOP, which in the case of TMS9900 is actually an unconditional branch.

After a great run in the competition last October, Erik is back. In essence, this could be seen as the completion of what he started back then -- adding an FPGA implementation of the TMS9900, enabling an entirely FPGA-based TI-99/4A clone. Erik steps through the implementation of the CPU, adding one bit of function after another in a very organized and workman-like manner. The end of April did not bring a fully functional CPU, but this remains a very well executed project.

James Diffendaffer

(Twitter free)
My entry into the 2017 RetroChallenge is to update the Tandy MC-10 BASIC ROM to include the ELSE command to improve compatibility with Color BASIC from Tandy's Color Computer, and to provide some performance optimizations.  A ROM image and documentation will be provided at the end of the project.

James cleverly picked a project platform close to my heart -- the MC-10, a cousin of my retro favorite, the Tandy Color Computer. James sets-out to improve the comptibility between the CoCo and MC-10 BASIC implementations. There is a fair amount of "2 steps forward, 1 step back", as many changes caused somewhat unpredictable breakage in other areas. Having done similar projects before, I suspect that the MC-10 ROM disassembly is a bit imprefect. Nevertheless, he completed the project. Jim Gerrie and other MC-10 BASIC aficionados of the world may now rejoice!

Paul Robson


I will remake the (probably) second released CPRG commercially "Dungeon Campaign" (as the month is probably going to be more like 15-16 days).

There's some information and screenshots here http://crpgaddict.blogspot.co.uk/2013/01/game-83-dungeon-campaign-1979.html

Paul attempts to clone an Applesoft game using a language called Typescript. I don't know much about that, but he posted his sources on GitHub. I do know about Git, so I downloaded the sources and took a little look -- I still don't know much about Typescript... ;-)

Anyway, by mid-month Paul had some credible stuff on the screen. Then it seems that real life intervened and he all but started over in the last few days! Well, he did get something on the screen and it surely looks like a game... Overall, a good showing from Paul!

Brett Gordon



The Drivewire protocol is a means of disk, time, printer, and tcp offloading designed for the Tandy Color Computer (CoCo) series by Boisy Pitre, and later extended a bit by Aaron Wolfe.  Drivewire is usually implemented on top of a streaming UART interface (or the Color Computers Bitbanger) as a stream oriented protocol.  

In a recent CoCoCrew Podcast (shameless brown-nosing the judge), John Linville noted that he found this project, and thought it would be neat to make something like this for the CoCo.   I think so too, and I'm one of a very few CoCo retro programmers who owns a prototype of Jim Brain's NIC card for the CoCo.

So, for RetroChallenge 4/2017, I will be combining the Drivewire protocol and my CoCoNIC card, and seeing what happens.  Stay tuned!

DID NOT FINISH, but sizable progress...

Norbert Landsteiner



Personal Computer Space Transactor 2001

Last time, we did a Computer Space simulator for a rather exclusive piece of hardware (one operational unit in total), this time, we'll redeem ourselves from any accusations of elitism by something more popular. As it happens (and Frank Linde has pointed out already), the Commodore PET 2001 is turning 40 this year. Accordingly, this time it won't be just a simple simulator, no, it'll be a Personal Computer Space Transactor (if you don't know what this would be, it's pretty much the same as a simulator, but using an even more inappropriate display technology). So we're going to explore character graphics and 6502 machine language and see, if this will add up to something resembling an arcade game that had been already retro, when the first PETs were being delivered ...

Norbert brings us another Computer Space project, and another fantasticly done blog to go with it! Norberts ports Computer Space to the Commodore Pet, and in the process provides a lot of detail on the technical differences between the platforms and what considerations were involvded in movin the game between them -- prolific writing and good diagrams and drawings. He even includes a primer on 6502 assembly language programming! In the end the project wasn't quite complete, but it is still a great project to have seen as part of this competition. Just be careful, Norbert, I can't control how many 6502 fanboys may read your blog and want to talk some things over with you...

Arduino Enigma



There are some cool kids out there making electronic versions of the Enigma Machine. They mostly seem to be some sort of microcontroller wired to 4x fourteen segment displays and pushbuttons to move the rotors and type the message to encrypt. I wanted to do the same but without rolling a custom PCB. A KIM Uno was laying around, having been used only to develop a 53 byte clock program. The idea was born to use the KIM to simulate an Enigma Machine. This 6502 program implements a 1930s encryption machine in a 1970s computer. It turns a KIM Uno into the cheapest physical enigma machine simulator out there.

The original, lever stepping only version was 703 bytes including the menu to change the encryption settings. The v2 gear and lever stepping enigma engine has already been optimized to be smaller than v1. The v2 menu system gained a third function to set the stepping mode. After optimizations, the feature richer v2 is now only 11 bytes bigger than v1.

The goal for this retrochallenge is to further optimize the code so its total size is smaller than v1.

For a bit of background, three rare, numbers only, Enigma Z30 were found in Sweden, an article in Cryptologia "Enigma Z30 retrieved" describes the wheel wiring. This machine can only encrypt numbers and the rotors have only 10 positions, it is thus perfect to be simulated in a KIM.Based on the published wheel wiring and some reasonable assumptions based on the architecture of other enigma machines, a 6502 program was written. The program has two parts, the core enigma functionality, the user being responsible for changing the machine settings via direct RAM manipulation using the KIM monitor and a menu system for a user friendly way of changing the machine settings. After learning that two versions of the machine existed, one with double stepping anomaly prone lever stepping and another with odometer like geared stepping, the program and its menu system ware modified to also support gear stepping.

Below are some demo videos of v1.


I had been looking for an excuse to make a new video of v2 showing the new F3 mode to select the stepping mechanism type and to shave a few more bytes off.

So here we have an Arduino, emulating a Kim, pretending to be a WWII-era German code machine. That seems a bit like a riddle, wrapped in a mystery...oh, whatever... But this is really a story of optimization, particularly of optimizing the 6502 code running on the (albeit emulated) KIM-1. I encourage enyone interested in the topic to read the "RC2017/04 Introduction and Wrap-Up" article at the blog, which describes the various techniques used to optimize the Enigma simulation program for size. Overall the code was squeezed down ~3%, which really isn't bad at all. Good job!

Paulo Garcia


I will try to port the  Hackaday project Slack for the Commodore 64 <https://hackaday.com/2016/11/29/slack-backwards-compatible-with-1982/> to the TRS-80 CoCo3.

The idea is to use the same proxy made for the Raspberry PI, but re-write the client to run on the CoCo3 using the standard serial port (not using a RS-232 cart).

The challenge will be complete when the application will be able to:

  • Connect to specific Slack team
  • Join any of the available rooms
  • Send and Receive messages on that room.
The CoCo3 will (probably) be written in machine language.

I will be blogging the progress over Vintage is The New Old. I will be creating a new category there so people can find it easily.

I am late for the game, but I hope I can pull that off!


Mike Spooner



Inspired by previous attempts, my modest entry to RetroChallenge this time is to interface a PS/2 keyboard to a 1987-vintage 68hc11 micro-controller; enough to at least read the scan-codes and twiddle the keyboard LEDs. And to write it up, hopefully illuminatingly.

Mike built a PS/2 keyboard interface for a 68hc11 microcontroller. I'm going to skip the recap/blow-by-blow and just recommend his "Lessons Learned (Dijkstra be Damned)" entry -- good reading there on a variety of lessons in both programming and in life, and it makes a good plug for Retrochallenge as well. Thanks, Mike -- I enjoyed it.

Stephen Barriball



I'm supposed to be demonstrating a ViewData system at the Wakefield RISC OS show at the end of April where I have a stand booked. So I will be sorting out the stuff required to make this happen.

Another ViewData project -- I may have to do some research and learn more about this stuff... Anyway, it sounds like Stephen's project was mostly preparation for the Wakefield RISC OS show. He gathered some hardware bits and did some cleanups and repairs, and he made his way to the show. It sounds like he drew some interest there, but he doesn't seem too satisfied with his overall Retrochallenge performance this time. Oh, well -- perhaps you have paved the way for something better next time?

Dαve Cheney


This is my late entry for the 2017/04 retrochallenge.

Notwithstanding my 2015 failure to launch, I plan to work on Arduino based emulators for various 6502 computers.

A few years ago I built an Arduino shield to host a real 6502 using the Arduino as RAM, PIA, and  glue logic. To some extent the software that this project ran was an afterthought, as it turned out the Apple 1 Woz monitor was perfect a proof of concept.

For the recent Arduino Day I brushed off my old code and reworked it to use an emulated CPU core so the sketch can run on an unadorned Arduino Uno or Mega. For retrochallenge 2017/04 I plan to continue this work.

UNCLEAR OUTCOME, can't find indications of progress...

Ryan Walmsley


The project is to build a Windows 98 Gaming PC to play games my Compaq 386 Luggable can't.

Ryan's project is a Windows 98 PC build. That _is_ old enough to qualify for the competition, and by the looks of Ryan this may be his first time around the block for that sort of work, at least with Windows 98!  Ryan did his research and gathered his selected parts, including a motherboard with ISA slots! It sounds like everything went together as planned, and more-or-less worked, until...

"Windows 98 works pretty well. However when applying the unofficial service pack 3 the menus all seem to want to view incorrectly and it also broke IE5 fully."

So, Ryan did truly recreate himself a true 90's era PC experiense -- well done!


  1. That's not a picture of me (Paul Robson) ;-)

    1. Pic stolen from your Twitter account -- send me another if you don't like that one!

  2. After seeing the activity in the twitter sidebar--> I decided to tweet at you from my old dead twitter account. 'carangil_mws' is Mark Sherman, if you want to update the above.

  3. "Just be careful, Norbert, I can't control how many 6502 fanboys may read your blog and want to talk some things over with you..." – That is, until they come across the PDP-1 vs 6502 comparison ... ;-)