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Vintage & Modern Tech Blog

About Me

Home videogames first appeared on the market in the mid-1970s. Not long after, I appeared on the planet Earth and, having repeatedly asked my parents for a Nintendo Entertainment System, received something of a consolation - in the form of a used Atari VCS.

My aging wood-panelled beast was well-served by a diverse back catalogue of titles not to mention that, when Atari rebooted the system as the Atari 2600 Jr, new titles were still compatible. Cartridges were expensive but, plenty of other kids wanted two-player matches, including on their own games. Social gaming was 'a thing' even back then.

During that time, a relative had been encouraging me to learn BASIC on their ZX Spectrum + 48k. In early 1992, they gave me the Spectrum as a gift. The commercial life of the Spectrum ended in 1993 but, having been banned from upgrading to a 16-bit console by my Stepdad, at a time when everyone from teachers to politicians were up in arms about the new problem of 'computer games addiction', I continued programming on my ZX.

When I broke it I bought a near-identical replacement, and used it all the way up to 1996, when a friend sold me a modified Amiga 500 stuffed into a white PC tower case with sellotape (he wanted it to look like a high-end Amiga 4000T) after I convinced my parents I needed a better computer for doing homework (cliche).

Not long after, at the careers office I said I wanted to be a Games Programmer but, as happened to so many young people back then, I found myself on a more practical (aka "boring"!) course in the form of an Apprenticeship in Information Systems Design. I stuck at the course and completed it but, the placement had not even been at a software house. Instead I had been typing and photocopying in an admin office. To cut a long story short I never worked as a programmer and ended up doing other things like restauranting and more office work.

Many years later, in 2014, I decided I wanted to get back into programming and decided to start by refreshing my skills through making some retro ZX Spectrum games. With four new Sinclair-themed devices announced in recent times, as well as other platforms, that decision seems surprisingly relevant.

Stephen Nichol
14th November 2016

My Homebrew Computer Designs (Beware! Techno-babble!)

The image accompanying this paragraph is a 3D render of my as-yet-unbuilt Z80 homebrew computer. I believed following in the footsteps of great homebrew enthusiasts of the 1970s and 80s such as Steve Wozniak and Steve Ciarcia by designing my own computer would be a worthwhile educational experience, and even incomplete it has taught me a lot about the inner workings of micro computers.

My design, drawn up in CAD in 2015AD, builds on Ciarcia's ZAP (Z80 Applications Processor) from the book 'Build Your Own Z80 Computer', using a single 32kb RAM chip instead of the several 0.5kb chips, and a memory paging system so the system can be 32kb ROM/32Kb RAM or all 64kb RAM so CP/M (a 1970/80s Operating System) or 64kb assembly language can be used. I also added an SD-card circuit, SN76489 sound chip (as found in BBC computers and the SEGA Master System), and a dedicated NEC 7220 video circuit with 64kb of dedicated colour video RAM.

It is my ambition to reduce the number of parts by using a CPLD (Complex Programmable Logic Device) and therefore cost in a similar way to the ULA in a ZX Spectrum and build the computer for real. Another unbuilt design of mine uses an HD64180 Hitachi - a legal clone of a Z80 that can address up to 512kb of RAM.

Stephen Nichol, 2nd August 2017

SELECTED SYSTEMS I'VE OWNED & FACTS ABOUT THEM

Atari VCS 'Woody'/'Heavy Sixer'

Photo: (Public Domain, similar Light Sixer)

Sold new from: 1977 to 1992

I owned one: 1988 to 1993

CPU: MOS 6507 @1.19MHz

Onboard RAM: 128 bytes (no Kilo,

Mega, or Giga here!)

ROM: 4Kb

Media: Cartridges

Memorable software: Asteroids, Night Driver, Breakout, Space Invaders.

Notes: 6 switches, wood panelling, paddle and joystick controls.

Sinclair ZX Spectrum + 48k

Sold new from: 1984 to 1986

I owned one: 1992 to 1996

(Actually two, first 48k+ damaged and unusable, 1994)

CPU: Zilog Z80A @ 3.5MHz

Onboard RAM: 48 Kb

ROM: 16Kb

Media: Most popular - magnetic tapes.

Memorable software: Dizzy, ATV Simulator, Turbo Esprit, Lords of Midnight, Wonderboy

Notes: 15 colours, QL-style keyboard, circa 25,000 software titles,

Supported for 11 years commercially, earned Clive Sinclair a knighthood for 'Services to British Industry'.

Commodore Amiga A500

Sold new from: 1987 to 1991

I owned one: 1996 to 2001

CPU: Motorola 68000 @ 7.09 MHz PAL

(NTSC runs at 7.16 MHz)

Onboard RAM: 1Mb ( 512k + another 512k as a

Slow RAM/Trapdoor RAM upgrade)

ROM: 256k ROM

Media: 880Kb 'Floppy' Disks

Memorable software: Bubble Bobble, Real 3D, Battle Cars 3D, Mikro Mortal Tennis

Notes: Many of the chips inside the A500 were custom made,

and had human names such as Agnus. The A500 was code

named 'Rock Lobster' prior to its release. A number of notable

musicians and artists have been associated with the machine and some, such as The Pointer Sisters even appeared in television adverts for the computer along with some NASA Astronauts.

Sony PS One Slim

Sold new from: 2000 to 2006

I owned one: 2001 to 2005

CPU: MIPS R3051 33.8688 MHz

ROM: Unknown

Media: Sony Format CD-ROM

Memorable Software: Air Combat, Tomb Raider, Driver, Medal of Honor.

Notes: The slim version, released 5 years after the original Playstation could have a small TFT screen, battery pack, and mobile phone attached for portable gaming and connectivity - although I never added these to my PS One - wow for the early 2000's, and so soon after mobile phones were made available to the masses.

IBM Compatible PC (custom, self-assembled)

Sold new from: Never

I owned one: 2006 - 2012

CPU: Dual core Pentium 4 @ 2.4GHz

Onboard RAM: 1.5 Gb + 128Mb NVidia Graphics RAM at 4x speed.

ROM: Unknown

Media: CD/DVD-ROMs

Memorable Software: Need For Speed: Carbon, Flight Sim 2004,

Flight Unlimited III, Darkstar One.

Notes: Built around a low cost system pull, upgraded slowly over time.

Sinclair ZX Spectrum +2B

Photo: Public Domain

Sold new from: 1988 to 1992

I owned one: 2012 - Present

(Manufactured by AMSTRAD,

following Lord Sugar's buy out

of Sinclair computers)

CPU: Zilog Z80A @ 3.5469MHz

RAM: 128 Kb (By 16kb Bank Switching)

ROM: 64Kb

Media: Mostly magnetic tapes. (It's sister the +3B replaced the tape drive with a 3" (not 3.5") floppy disks. An interesting call from Amstrad, the 3" proved less commercially popular than 3.5" disks.

Memorable software: Soundtracker, PAW.

Notes: From the +2 upwards, the ZX Spectrum has an integrated tape or disk drive. The most RAM an 8-bit CPU can detect is 64Kb so,

paging techniques are used, for example later levels are held in the extra RAM until needed.

Nintendo Wii

Sold new from: 2006 to 2013

I owned one: 2012

CPU: IBM Power PC "Broadway" @ 729 MHz

Onboard RAM: 512 Mb Internal Flash + non-publicised Graphics RAM

specifications.

ROM: Unknown

Media: Nintendo format optical disc

Memorable software: Wii Sports, Wii Fit, Tiger Woods PGA Tour 9, Doctor Who: Attack of the Cybermen.

Notes: controllable through motion detection. Has 4 legacy controller ports underneath a panel at the top of the console.

Sony PS2 Slim

Sold new from: 2004 to 2013

I owned one: 2013 to 2015

CPU: Emotion Engine @ 299MHz with 128-bit SIMD capabilities, plus

'Graphics Synthesizer' @ 147.456 MHz

RAM: 32 MB Direct RAMBUS, 4MB eDRAM

ROM: Unknown

Media: CD/DVD

Memorable Software: Ace Combat 5, Need for Speed, Lemmings.

Notes: Backwards compatible with PS One games. Can be used as a

DVD player, for watching movies etc.

Niche Machines FIGnition (8-bit)

Sold new from: 2011 - 2015 (self-assembly solder kit)

I owned one: 2014

CPU: AtMega328 @ 20MHz

RAM: 8 Kb

ROM: 1Kb

Media: Internal Flash Storage

Memorable software: Brikky (Breakout clone)

Notes: the only computer I have ever soldered together.

Has an unconventional 8-button entry system, and was

Built in language FORTH, not BASIC. B & W mono Graphics. It was largely influenced by the Cantab Jupiter Ace - an early 1980s computer manufactured by a pair of designers who broke off from Sinclair.

AtGames Arcade Gamer Portable

Sold new from: 2013

I owned one: 2014 - 2016

CPU: Unknown System On A Chip (SoC)

RAM: -----

ROM: -----

Media: None, 30 built-in games only.

Memorable software: Alex Kidd in Miracle World, Ecco, Sonic.

Notes:Price £20 to £30 new, built-in screen or composite link to a television. Contains a mix of SEGA Master System and Game Gear games. Games officially licensed to AtGames by SEGA.