Ben Heck's ZX Spectrum 2.0 Part 2

Ben has modded many old computers into gaming portables and in this episode Ben returns to an old friend - the ZX Spectrum. In this episode he completes the project. bit.ly/1jh94OG
Learn more about Analog Devices at bit.ly/1Oq2GQU

[@nevermnd001]

I really appreciate Ben's honesty on this one. That not *everything* always works out quite right the 'first time'.

[@MattsPaddock]

Ben, you're the man! Hats off to your projects!

[@Workshopshed]

Great build, I look forward to the ZX Spectrum 3.0 in 2016

[@GingerNingerGames]

Watching this show again is relighting my motivation for creation, I've been DIYing cases for things for a while and jury rigging stuff (Xbox one most recently) But now I want to do an electrical engineering course or something so I can properly understand these old circuits and how they work.

[@SmoothEmJay]

Thing of beauty, Ben. VERY well done sir.

[@Skylance87]

I'd love to learn more about circuitry and be able to do all this but i love watching how these come together

[@matthewmillaisgray]

Dear Ben & the Team, just an appreciation for that excellent & inspirational work there! This is rich & engaging in its imaginative & creative energy. Thank you for sharing the fun

[@jessendelft-1]

@18:08 Ben made some nice sparks with the soldering iron :P

[@KingBaziaNew]

+Stuart Wilson They use the same effect when milling the heat sink and when bending it whit the hammer. I guess someone in editing was bored.

[@MelroyvandenBerg]

+Jesper van Tol I also noticed it ahah nice. It's probably because of the battery

[@ugoleftillgorite]

You knocked it out of the park with that case design, Ben! You have made a ton of progress over the years.

[@igotes]

As others have commented, it's nice to see a modern Spectrum "clone" that isn't simply an emulator running on a modern CPU. Top work!

[@kelli217]

Had you considered the possibility of putting the two main ICs on the back of the main board, in order to reduce the thickness of the screen area? Would that have caused problems in PCB layout, or maybe prevented you from mounting a heat sink? Had you considered milling fins on the heat sink to increase surface area and therefore heat dissipation, or was your existing design sufficient for the ULA's heat output?

[@wokani_za]

Great job Ben. I can think of a bunch of things that could've been included here but of course as you have mentioned the schedule for these episodes is tight. But if time and board space allowed for it I would've probably added the following. 1. Composite video out port for connecting to a CRT or LCD tv. 2. integrated USB keyboard circuitry. Some modern expansion devices include this. 3. Integrated the DivIDE (or similar) circuitry for fast loading of games from CF/SD cards. 4. Bus expansion port for adding any of the modern expansion devices built these days. With the above added you could carry with you a device that can load thousands of games at lightning speed. It can also be used like the original unit by plugging in an external keyboard and TV and possibly a joystick of that expansion device is added.

[@PaulTaylor1]

Got that book for Christmas a few years back, absolute solid gold. :-)

[@TheTurnipKing]

15:16 FYI, the extra space in the load command isn't required with the original ROM. 21:05 The ULA runs warm because the Speccy actually drives the Ferranti ULA above Ferranti's design specs for the chip, using more of the gates at once than Ferranti actually expected. But hey, if it's still working in 2015, I think we can probably call it a stable design.

[@muh1h1]

Who the hell did the Audio mixing on this one?

[@xKatjaxPurrsx]

+muh1h1 AND NOW A TECH TIME SHOUT!

[@stonent]

+xKatjaxPurrsx Yeah I had my audio maxed out and then it blared on the speaker.

[@hingeslevers]

Wow, that turned out great. I really like the design, a really good homage to sinclair's superb aesthetics

[@DavidPerry.]

Ben you are a rockstar! Looking forward to Spectrum v3.

[@Gambit771]

Very nice work on the ZedX Spectrum. The case looks like something from the early 80's too. :)

[@allluckyseven]

Is there a way to emulate the behavior of a PCB on a computer before sending it to be manufactured? By that I mean something like being able to load a program onto the emulated computer (a "virtual ZX Spectrum" in this case), to test it and avoid having to mod it later. I understand the thing about time constraints, but y'know, Ben had to spend more time compensating for that. I loved these episodes, by the way. It's great seeing him build a whole retro computer almost completely from scratch. Hope there will be more like them in the (nearest) future! I wouldn't mind if it needed a third episode...as long as they were uploaded in sequence! (grumble-grumble -- **shakes fist**)

[@dudenamedclem]

I'm so happy Ben chose NOT to go with a laser cut wood case for the project, it looks damn sexy in black.

[@FinalBaton]

love the form factor of this project! Very well done

[@waltercomunello121]

ok, all we need now is "the length of an episode of Duck Tales" as an official unit of time.

[@axs203]

You sure know your stuff Ben! It's good to see you make mistakes and just get stuck in.......I wish I could do what you could......to be able to build so many cool things......and put together a whole spectrum....wah!

[@JokelesComedian]

I think the device looks great and with the 80's theme maybe add a removable, flip, or slide cover over the keyboard for storing and decorate that as well.

[@MrApaHotel]

They really have found the right guy for this show :-)

[@retrobluehawk]

This is fantastic, I am always in awe of your engineering knowledge and skills Ben. There are plenty of ZX Spectrums still in existence, you can pick one up for quite cheap, what I was wondering is can you make an MGT Sam Coupe, a ZX Spectrum compatible 8 bit computer with better graphics and sound. These are much rarer and much more expensive, so if you could engineer one for cheaper than you can buy a 2nd hand one, it would be most interesting.

[@xXTheoLinuxXx]

That would be awesome! I've never seen a Sam Coupé in RL, Those were very very rare in Holland. A normal pcb that fits in a regular pc case would be fine :)

[@jamesgrimwood1285]

So here we have a complete working smaller ZX Spectrum, created by one person over a few months. And then elsewhere on the Internet we have the ZX Vega :-/

[@hingeslevers]

+James Grimwood I mean what's the deal with a Speccy that you can't program with? What were they thinking?

[@jamesgrimwood1285]

Or one that has no built in joystick. Emulating a kempston or cursor joystick isn't a massive task any more...

[@jarrodbentley903]

+James Grimwood don't forget the Harlequin, just speccy 128 full sized pcb that fits in existing 48k/+/128 cases

[@hingeslevers]

Jesse, I think James was still talking about the Vega.

[@TheTurnipKing]

+10p6 Actually you might as well get a Raspberry Pi and run FUSE. Even allowing £20 for peripherials you're gonna need, you're still about £50 up over the VEGA and have a far more capable device. I'm hoping someone retools Ben's speccy board so that it can take original keyboards and be used in the original case. Also seems like there's some scope to emulate parts of the ULA using a cheap microcontroller. Imagine using something ike an Arduino to load ROM images from SD card, dump them into the memory, set the processor state and drive a clock signal to the z80, thus bypassing (and eliminating the need for) tape loading entirely? Also, this seems like it would dovetail nicely with Ben's Master System/Colecovision/CPM z80 project.

[@StephenButlerOne]

Love how 80s this looks. So period specific. Also love that you use as a £650 phone, with oodles of power to load it. some type of irony in that I'm sure.

[@mamanmatty]

Great stuff. You made me think the world is good again

[@MichielHaisma]

Absolutely beautiful.

[@bcsuda]

Hey that's a great episode. Thanks for spending some time showing off the finished product from different angles, as well. That was very nice. Cool project and great result. I think Ben is right when he says it's one of his better builds. Now, the only thing is the audio in most of the episode is a lot quieter than the intro and Tech Time Out. Maybe the mics' gain were down?

[@lithuanianscot7172]

ZX81 had a simple modification used at the time. A switch called a video inverter. It just switch black with white and that is about as simple as you get.

[@Quazatronn]

Great video, Ben! You're such a great talented person!

[@brandonlewis2599]

Ben, it's good to see you using 123d more. I wish 123d could export sketches. Then you could laser cut from your 3d model rather than having to lay out all your parts twice. One trick I've found when printing enclosures with a curved face is to print them face up (i.e. opposite of the way you printed it), but to use support material underneath, which you then remove. For some reason, printing a curved shape works better this way. I think it's because the layers underneath tend to sag. In any case, the interior of the case will be a little rougher this way, but who cares? I'm experimenting with sanding PLA. I also found an epoxy sealer for smoothing 3d prints, but have yet to try it. It's called XTC-3D.

[@xanokothe]

ZX Spectrum 2.0 is really impressive. I'm looking forward for the FPGA version!

[@neileyre6019]

Hi Ben, Very nicely done mate, almost perfect in fact. I think I would prefer yours over one of the re-designed and commercially available ones. If you could include a memory card to have games instantly available rather than have to load tapes, this would be more desirable. The finishing touch would be the spectrum colours in the corner...a perfect modern speccy. OH and maybe a USB for a joystick?? Yes Zed is better than zee and also we say soLder with the L and not sodder which doesnt have an l :) Just a UK-USA thing mate!(one of many) Finally, I have just watched all the videos you have on speccy reworks and have thoroughly enjoyed them, well done mate. I hope to see more on the speccy from you. I think your design would be a sell-out in the UK with all us 40ish guys.

[@Epic_DaVinci]

Turned volume up for opening speech, Ears set on fire when intro came on.

[@HuntersMoon78]

The completed shape looks like a ZX81

[@duncanwalduck7715]

Also not far off a Psion series II - but much more desirable.

[@Decco6306]

Ah yes, the doorstop

[@julianskidmore293]

Worth noting that at 6:14, Ben Heck has a copy of Chris Smith's definitive guide to the ZX Spectrum ULA. www.zxdesign.info/book/bookAnnounce.shtml

[@Shundi12]

The design of this version is great. I love the gold and black colouring, it definitely looks like something out of the 80s. Could you do something with a C64 next? This was my first computer and I remember playing some great games on that like Dizzy. Also the music from the C64 is great.

[@610annasinclair]

you should do a kickstarter for this as i know lots of people would love it

[@benadams6332]

Nicely done!

[@SimonJackson13]

You could have put 2 extra bit planes and 4 colour tables in the 16kB hidden, and some nibble pairs for multiplying the regular and extra screen bitmaps. Maybe the ULA in a CPLD, and given the speed of modern parts, it might have been possible to CPLD a RISCy set of micro-ops to make a simplified Z80 via little subroutines in the mem too, all in one CPLD :D

[@jarrodbentley903]

a more modern equivalent voltage regulator negates the need for a heatsink on the 48k speccy (and toastrack) which also reduces the ULA temperature too

[@Porco1984]

Very cool project, I think it turned out quite good! Would love to see a portable Amiga 500 or something like that :)

[@FireDragonAndromeda]

Damn, I'd love one of those. Still have a ZX Spectrum 48k.

[@ottersdangerden]

There is a programming proverb that goes along the lines of "2 hours or programming saves you 20 minutes of planning"

[@FailsafeFPV]

I Love Ben Heck! He is so creative!

[@kamshaft70]

Very cool project!

[@ChozoSR388]

That looks pretty damn retail, Ben! If I hadn't known you built it, I'd have thought you'd bought it.

[@cfaulkingham]

Nicely done.

[@StingrayOfficial]

Well designed, actually pretty attractive. My first compute was a zx81 I bought from a garage sale in 90 or so, came with the books and everything, taught myself how to program it. Now look at me, making dumb comments on youtube.

[@AdamsOlympia]

I see the awesome Form 1 stereo-lithography 3D printer in his office now. Wondering if Ben has covered/reviewed it in any of his videos.

[@jameslewis2635]

I would like to see if this could be done with more complex computers such as the Amiga 500 or Atari ST of the 16 bit era. These were the computers that most people switched to when the Speccy and C64 had become too outdated. They would also be better for a hand-held game system because of their better resolution options, colour pallet and hard drive support (SCSI) which can be converted to memory card for storage. The main problems would be the amount of custom chips (mainly on the Amiga) and squeezing in all the functionality while keeping the size down and providing adequate power.

[@cr76802]

very nice.. my first computer I had to mod to work was a Amiga 2000. played endless hours of sim city and nuclear war.

[@sishims5066]

15:08 Technically you were supposed to put the name of the programme to be loaded inside the quote marks. However leaving it blank would load the first program you throw at it.

[@Brian.S]

Was having a similar issue (RAM not being activated) in a Z180 project I'm working on, but thankfully it wasn't a hardware problem. It turns out that you have to use the Z180-specific I/O instructions to work with internal peripherals, like the MMU (doh!).

[@gameworkerty]

That's really pretty! I'd like to see a rainbow on there too.

[@wolfgangschweiger9557]

YES - Manic Miner, my favorite then in the early 80's. Followed by Jet Set Willy - yeah! Nice project, maybe I'll follow you...

[@Gambit771]

+Wolfgang Schweiger That was a good choice of game to pick

[@tokki_]

How does this only have 75k views after more than a year?

[@sarreqteryx]

you could have made the screen section a bit thinner if you had inverted the front am back of the main board underneath. have the z80 and ula on the back, and the multiplexers on the front. also the ula's multiplexers arranged inside the ula the way you did with the z80's

[@rootbeer666]

I had very good luck using Isopropyl alcohol as a cutting fluid for aluminum. I got professional grade finish using my desktop mill.

[@rootbeer666]

Definitely better quality than your cut.

[@PlasmaHH]

11:00 or they called them bodge wires, or they were just part of the design because adding another layer was not feasible but running a couple of wires instead of these traces was.

[@skynetcybernetics9058]

"Everything kills you in this game." - Welcome to the 80s

[@MrAdminaras]

for some reason it reminds me a lot of the first game boy :-D . How about adding a power indicator using an RGB led so that you can also display battery level. You wouldn't want your space invaders game end just because you didn't know how much battery is left!

[@jaycee1980]

One thing I did spot was that the spectrum seemed to initialise very quickly. This would imply it's only detected the bottom 16K of memory, and not the full 48K. I'm also not sure why Ben chose to use the original Z80 chip here... I probably wouldve used a modern PLCC packaged one which is CMOS and would consume much less power. edit: judging by the fact that the games all work, I'd say the GW ROM mustve sped up the initial RAM test!

[@theneroliveira]

it looked really fine.

[@bytemarc8550]

Seriously impressive

[@matthewkriebel7342]

"It definitely semi-conducts." Haha, that has to be a new electronics lab catch phrase.

[@Roobotics]

18:09 Spark! What shorted? The battery isn't even connected. Also funny about the PU resistors under the IC, I nearly had that bite me today, so easy to forget about component outlines.

[@rlamb51]

I remember working with the Zilog ZEE/ZED? 80 in engineering class about 23 years ago and while the construction techniques are interesting and I enjoyed the series, I'm wondering why? I haven't used a tape/audio drive programming since my Commodore VIC-20 and it was all typing 1&0 machine language code (maddening). Pascal was sent from heaven and C- was oh wow!

[@rlamb51]

+Stuart Wilson I was an electronics technician when affordable Personal computers were first introduced. I worked my way from the Vic-20 to the C64 to the Commodore Colt (XT clone) in the late 80s and after teaching myself basic and pascal. I graduated to C/C++ on the 486sx in college. I still have my Colt but its wrapped up in the attic now. Just couldn't part with Old Sparky.

[@rlamb51]

+Stuart Wilson the colt came with two 5 1/4" floppies. I installed a 10 Meg HD

[@gregryan7761]

I always wanted a speccy laptop, with a decent sized screen, at least 14". A decent keyboard is a must, not the dead flesh feeling keyboard that was original. and to be able to switch from the original ROM to a "better" modded ROM on the fly is a must. I don't see why such a project couldnt have the circuits added for the joystick ports, since they are only a couple of A/D chips. If you really want to go all out, add a sound chip. I think that was an option back in the days when this was fairly new, a add on circuit that a person could purchase and connected to the rear bus. Maybe I am wrong?

[@davelister1]

Good stuff here ! and yes I used to do that for a living.

[@allluckyseven]

5:14 -- Whoa, a "whoosh" sound there with no graphic going with it. Also, what happened to the video encoding? Ben's mouth glitches many times during the final "what have we learned" bit.

[@jetli740]

amazing project, if these were release in the day of the spectrum it would sold millions

[@LucasTax97]

Ben, I'd love to see you redo the apple 1 project in this same manner, especially if you share all the design files.

[@nekomasteryoutube3232]

Would it be possible to smooth out the case a bit? I was thinking maybe fine grit sand paper on the outside of the case to smooth down the lines that formed from the 3D printing, and/or maybe use a bit of acetone to give it a smoother finish.

[@tonymahboi]

a dedicated addon that runs tape files would be interesting, something that attaches flush and looks the part.

[@gabodrg]

That's a really powerful solder paste at 8:42

[@zedmanatutube]

Thanks Ben love the videos

[@thermodynamicist]

Still not enough rainbow!

[@JacGoudsmit]

8:10 "I think it's our boards from OSHpark! Me: Nah it can't be, OSHpark uses custom purple envelopes... ;-)

[@zaneyoumans2923]

Thank you for the Reading Rainbow reference

[@Stabby666]

I've got that book, it's great!

[@samull4946]

ok, tape loading works. ITS TIME FOR A TECH TIMEOUT

[@SharpblueCreative]

Ben I'd love to be able to this, though I'd love a BBC Micro 32K portable.

[@Nukle0n]

I thought ChipQuick was for removing surface mount chips, and not to be used as solder paste?

[@GeorgeGraves]

+Nukle0n ChipQuick is the company name. They sell normal solder solder as well.

[@KB1UIF]

The audio levels changed so much I was constantly adjusting my audio levels to compensate !!!

[@jonilarsen-haikarainen8733]

The sound level on this episode was all over the place....

[@letsgocamping88]

Will you be making the fixed eagle cad designs available for folks who fancy making their own?

[@Malcolmstuartcole]

I liked my keyboard....a lot ,and my microdrive.I did the interupt mod no internet in those days had to wait for weeks for answers in computer magazines....always trying new tapedecks and ajusting the azimuth for sweetest loading....can you print silicone?

[@kulgan96]

i would try add a switch on the speaker so it can be disabled when loading those nectar for the ear tapes

Will the Eagle SCH and BRD files be published?

[@ZXSpectrumvideos]

I wonder if you used a mono cable or a stereo cable? Here in Portugal is hard to find a mono cable and with stereo cables the games don't load. One thing I would do different, the 48k model is the best as a computer design, but the 128k is better for gaming, has better sound and more ram to run better games, so I would build a portable spectrum that look like the 48k but it would be based on the 128k. Still is a very good project you made there, keep up the good work, and I hope to win it :)

[@AstAMoore]

It resets too quickly. Unless part of the reset routine was edited out, it looks like the Speccy only sees 16K or RAM. (Manic Miner was written for the 16K Spectrum.)

[@neogain]

awesome Project. Well done. Ben, pls due the same with the Amstrad CPC464 :)

[@zedexspectrum4266]

You should totally consider selling a set of Kits minus the ULA, Facebook Sinclair For Sale .I know members would climb over each other to buy one :)

[@MultiGamerKingdom]

i love your show

[@BrainSlugs83]

RE: "What should I have done differently?" -- You should modify the design, replacing the ULA with an ATMEGA or Propeller instead of the original chip -- then you could add features that let you save and restore the RAM state to an SDCard -- that way you only ever have to load a game from tape once -- do a RAM dump, and bam. -- You'd have to modify the ROM image a little to facilitate the saving and loading of all the registers as well. -- Also you should interface to the ROM chip via the ATMEGA instead of directly -- this way you could make sure it only reads the state of the switch at boot-up (i.e. you are never in danger of hot swapping the ROM image while the system is running...), plus it gives you the option of using a modern SPI eeprom, or just storing the rom on the SDCard...

[@BrainSlugs83]

If you went with a propeller design you could even remove the analog video chip and just use the propeller to generate the RGB...

[@chaos.corner]

You should be able to do it with the original ROM and ULA. There was a device available for the +3 that would snap games to a 3" floppy and restore them (and let you poke as well, I think). Or if you want the original experience, you could add an arduitape in the case.

[@1invag]

Michael Jensen but then it wouldn't be a homage to the z x spectrum lol itd be something completely different

[@hm-bh9ni]

Michael Jensen

[@TheTurnipKing]

yep: Multiface. Basic principle, uses the CPU NMI line to freeze operation, and make a copy of the contents of all the RAM and registers and is the basis for the snapshot (.SNA) file format which was a mainstay of the early Spectrum emulator scene but there were some limitations for the purposes of preservation: Things like the loading screen art would often be lost this way. Later intercommunity efforts got us the TAP file format and descendants that support a whole variety of early 8-bit home computers that used tape files, allowing the emulators to emulate the whole process of loading from beginning to end, both at original and accelerated speeds.

[@RaySpark]

It is possible to build in some cheap mp3 player or something like that, to load "tapes"?