Redesigning the ZX Spectrum 128k - A lifelong dream

edited August 2016 in Hardware
Hello,

I am myPinballs (Jim) and i run a small business here in the uk making replacement 8-bit hardware pcbs for arcade pinball games as well as writing new software for old games. I'm new to this forum, but have been an avid ZX Spectrum fan for a lifetime and have been working on a clone pcb board for the zx spectrum 128k for the last 18 months or so, alongside my other arcade projects. I have some details on my progress with it below. I'd love to share the details with you and get your comments. I also attend the PlayExpo event in manchester every year in the Pinball and Arcade section running a 'hacking lab' and will be demoing my ZX Spectrum project detailed below this year on my stand. If you go to this event please look out for my stand and i'd love to chat to you about the project and ZX Spectrum stuff in general :)

Details below : :)

The ZX Spectrum was my favourite thing in the whole world when i was 8. It's what led me into a world of software and hardware design. Every since i first got a rubber keyed 48k, i always thought one day i'll make my own, never really thinking that it would be possible. However with my lifetime of 8-bit pinball hardware repair knowledge always expanding and with me developing my own range of replacement cpu and sound board hardware for various pinball systems over the last few years the thought reappeared in my mind and now didn't feel to far away :)

If you would like to read more about this project i have created an article on my blog page describing the last 18months development of it :) http://blog.mypinballs.com I wanted to create a 128k pcb board as i love the AY-8912 music so much. This chip is used in arcade games to from the same era and has such a cool sound. Also some of my favourite games from years gone by had extra features for the 128 like renegade. This project will be part of my NLP stand this year, so we should all be able to have a go on some classic games including the advanced pinball simulator :D

Also here are some pics of how its looking now :) Do you remember the 'Advanced Pinball Simulator'??

pcb1.jpg
rtype.jpg
pinball.jpg
space_invaders.jpg
pcbwithtape.jpg
jetpac.jpg
manicminer.jpg
horace.jpg
horace2.jpg
rampage.jpg
rampage2.jpg
commando.jpg
decathlon.jpg
tapper.jpg
hypersports.jpg
greenberet.jpg
midnight_resistance.jpg
outrun.jpg
renegade.jpg
robocop.jpg
pinball.jpg
pcb1.jpg

The board is now working lovely, has been a major learning curve with some tricky moments, but has been so rewarding. I'll be making my first batch of assembled boards and kits soon so you to can have a new 128k Spectrum in and old case :) The boards will be available like all my other pcbs and products on my web store here.

http://mypinballs.co.uk/electronics/store.jsp

The new boards will feature:

• Reduced chip count and power consumption
• Reduced custom chip usage
• Fully spectrum 128k compatible
• 8 pages of 16k ram 128k total
• High quality picture - RGB scart socket with proper tv identification capability.
• Standard female 21 pin socket for use with stock fully wired scart cables
• Built in kempston joystick port
• Built in IDE 40 pin connection
• Uses the 128k ULA IC - Ferranti 7K010E/Amstrad 40056
• Full set of test pads
• Power leds
• Low power 5v regulator
• Single 12v supply power in
• Modern reset chip and on board reset button
• AY-8912 sound generator on board for retro 80s music
• AY-8912 expansion connector for 3rd party dev
• Sound line in for Tape loading or loading wav files
• Sound line out for connection to amps and playing music
• Fully compatible card extension port
• Full plate through design, no SMD
• Designed and assembled in UK

Finally some videos with classic 128k music (similar to the wonderful gottlieb 80b pinball games from the same era :))

[MEDIA=youtube]leDFvm_Jmvg[/MEDIA]

[MEDIA=youtube]1YoH_pwqVKA[/MEDIA]
Post edited by myPinballs on
Thanked by 3DavidB morph 1024MAK
«13

Comments

  • edited August 2016
    Nice, I shall be sure to have a look at PlayExpo, :D

    Also, note that you need to upload the pictures somewhere and place the links in the post, they are not displaying here, :)
    Post edited by polomint on
    So far, so meh :)
  • great stuff :)

    pictures work fine for me.
  • Is this ULA readily available as new, or is it taken from an actual (donor) 128k Spectrum?

    Either way this looks really smart.

    Also, sorry if I missed it somewhere, but what's the big thick ribbon cable on Photo #2 connected to at the other end?
    Myke-P
  • MykeP wrote: »
    Also, sorry if I missed it somewhere, but what's the big thick ribbon cable on Photo #2 connected to at the other end?
    That has to be the SCART cable.


    Website: Tardis Remakes / Mostly remakes of Arcade and ZX Spectrum games.
    My games for the Spectrum: Dingo, The Speccies, The Speccies 2, Vallation, SQIJ.
    Twitter: Sokurah
  • edited August 2016
    MykeP wrote: »
    Is this ULA readily available as new, or is it taken from an actual (donor) 128k Spectrum?
    ...

    I believe it has to receive one from a donor 128K Spectrum, and that is my only concern for this project.

    It's a good alternative for the ones which have a dead 128K board.
    Good work and congratulations on following your passion @myPinballs..

    Post edited by RMartins on
  • looks like an excellent alternative to the just speccy 128 and with the slam coming no donor ulas would be required
  • MykeP wrote: »
    Is this ULA readily available as new, or is it taken from an actual (donor) 128k Spectrum?

    Either way this looks really smart.

    Also, sorry if I missed it somewhere, but what's the big thick ribbon cable on Photo #2 connected to at the other end?

    Yes, I built the board with an RGB SCART out connection, but may also add a std VGA out to. The picture quality on my tv during testing has been awesome! Even better than i thought it would be :) and the signal is correctly identified by the tv, as i've followed the full SCART spec for RGB out. . I wanted to use the standard scart connector for ease of cables etc even though its pretty large!

    Yes, it is using a 'socket pull' ULA or spare part - Ferranti 7K010E/Amstrad 40056. Maybe they'll be replacements for these one day, but for now its from a donor machine or supplied from me. I'm building up a stock of them myself.

  • RMartins wrote: »
    MykeP wrote: »
    Is this ULA readily available as new, or is it taken from an actual (donor) 128k Spectrum?
    ...

    I believe it has to receive one from a donor 128K Spectrum, and that is my only concern for this project.

    It's a good alternative for the ones which have a dead 128K board.
    Good work and congratulations on following your passion @myPinballs..

    Correct, I aim to offer the board with a ULA or without if you want to provide your own.

    It is a passion for sure and has been many hundreds of hours, but all worth it to see those games loading finally :)
  • Good work indeed. With the new ULA replacements, that's one less problem too.

    You mention the ide port. What dos are you using?
    No one important.
  • Is there a link to the new ULA replacements? I'd like to read up on this.

    Also if anyone has a favourite 128k game with nice music they'd like to see i can test some more out on the prototype and maybe video a few. I've tested a lot of games out (my favourites) to see how it loads and runs, but some others would be cool to. As i mentioned at the top i'll be at Play Expo to if you want to see it in the flesh and chat to me. My stand will be in the pinball area :)

    Commando is my favourite game at the moment. The music is super cool and plays throughout the game. My favourite back in the day was R-Type and is still one of my favs. The coding on this game is simply unbelievable! As a coder to, i really take my hat of to the guys that did it :)
  • myPinballs wrote: »
    My favourite back in the day was R-Type and is still one of my favs. The coding on this game is simply unbelievable! As a coder to, i really take my hat of to the guys that did it :)

    Have you read this e-book by Bob Pape - the coder of R-Type? It's a really facinating read.
    http://bizzley.com/
    Website: Tardis Remakes / Mostly remakes of Arcade and ZX Spectrum games.
    My games for the Spectrum: Dingo, The Speccies, The Speccies 2, Vallation, SQIJ.
    Twitter: Sokurah
  • Why scart socket instead of mini DIN for example? It's ugly, huge and totally flimsy - by design. I know I should be thankful for the scart as we have RGB ready CRT TVs around Europe but its physical implementation is a clear disaster.
  • This looks great.

    I am from that generation, when Pluto was still a planet, and the Earth is round.

    Bomb Munchies on WOS thread
    Bomb Munchies Ver1930 17th Nov 2017 (look for the blue download box ) If you get a time-out message and live in the UK then try after 9pm-3am.
    Send me a PM and I can email it to you too. Kent, UK
  • Sokurah wrote: »
    myPinballs wrote: »
    My favourite back in the day was R-Type and is still one of my favs. The coding on this game is simply unbelievable! As a coder to, i really take my hat of to the guys that did it :)

    Have you read this e-book by Bob Pape - the coder of R-Type? It's a really facinating read.
    http://bizzley.com/

    Wow! That's awesome. I'll be taking a look at that most definitely. :)
  • maiki wrote: »
    Why scart socket instead of mini DIN for example? It's ugly, huge and totally flimsy - by design. I know I should be thankful for the scart as we have RGB ready CRT TVs around Europe but its physical implementation is a clear disaster.

    I've included the standard scart connector so that there's no 'special' or custom cables required. I actually like the scart connector myself, as it has many different options including the very good RGB out and is included on almost every tv made, even new LED ones today. I haven't had any issues with 'flimsyness'.

    I'm also considering including a VGA out connector (std 15 pin d type), as the extra sync required can be included with a few extra discretes and a spare gate.
  • VGA would be nicer for me here in the USA where scart isn't used. Looks very interesting!
  • Kempston joystick interface hardware section population and testing progress with zipstik

    kempston1.jpg
    kempston_detail1.jpg
    kempston2.jpg
    kempston3.jpg
  • Damn, you well and truly beat me to it ;)

    I think the only difference in our plans, is that I wanted to use modern SRAM instead of ye olde DRAM, but pretty much everything else is as I intended. Well done!
  • This looks great. Can anyone recommend a tool to use to cut into cases to accommodate the joystick port etc?
  • Not sure if it's the best option, but I've used dremel.
    http://iki.fi/sol | http://iki.fi/sol/speccy/ | https://github.com/jarikomppa/speccy
    http://goo.gl/q2j0NZ - make ZX Spectrum choose your own adventure games, no programming needed (release 3)
  • I'd have said a dremel also, then a bit of sanding.

    funny you put pic of rampage loading screen.. I own the digitiser used to generate it, which I bought in recent years off the maker :)
  • Ok, thanks for the suggestions.
  • Jim M wrote: »
    This looks great. Can anyone recommend a tool to use to cut into cases to accommodate the joystick port etc?

    Dremel should be the best option i think as others have said. I've designed the board to make sure only the bottom case needs 'adjustment' I'm also thinking it would be cool to design some new 3d printed lower cases that would accommodate my board without hacking up an original case, but that's just an idea at the mo. Shapeways that i use for other plastic items in some of my pinball projects have super great quality now a days.
  • edited September 2016
    jaycee wrote: »
    Damn, you well and truly beat me to it ;)

    I think the only difference in our plans, is that I wanted to use modern SRAM instead of ye olde DRAM, but pretty much everything else is as I intended. Well done!

    Yes i used larger dram chips to help on the chip count and make life simpler for the ULA side. If you are going to Play Expo in a couple of weeks stop by my stand (in the pinball area) and i've love to chat to you about it, and you can see it all first hand etc :)

    Cheers

    Jim
    Post edited by myPinballs on
  • Some final tests for the setup coming to the Play Expo event in a couple of weeks. 8th - 9th October over in Manchester. Bought a new 32" TV for the event and been playing about with the settings. The Zoom2 option seems to give a good full screen image especially for R-Type so will give that ago and also have the regular 4:3 option to.

    game_demo_large1.jpg
    game_demo_large2.jpg
  • I would love to see this!

    I will be at PlayExpo - interestingly PAT - testing the PinBall Machines ;)

    It will be nice to drop by and see what mischief you have been up to ;)
  • This is absolutely amazing!
    Good work Jim, and good luck with any future developments. :D
    Author of BertoMenus, soon to become BertoBASIC +3 ;)
    Feel free to help yourself to the Sinclair ZX Spectrum +3 Manual.pdf
  • Hello can I buy this from somewhere ? I have a spare spectrum+ case that I could use so then I'll have both a 48k and 128k :)
  • This is such a neat project! I, too, look forward to board/kit availability.

    - Alex
  • ivanb303 wrote: »
    Hello can I buy this from somewhere ? I have a spare spectrum+ case that I could use so then I'll have both a 48k and 128k :)

    Yes i will be making the boards available through my web store here - mypinballs.co.uk/electronics/store.jsp in due course. I will keep everyone interested here updated with progress aswell. The first batch revision board blanks will get ordered when i'm back from expo.

    Reminder of the event dates - 8th - 9th October in Manchester - playexpomanchester.com. Come to my stand to see the proto in full action, have a chat with me and see it all first hand along with my other pinball and arcade projects. Its only a few days to go now. I am packing up my stuff as we speak :)
Sign In or Register to comment.