@@networkg Troubleshooting can definitely be fun, especially when it's successful, but when the actual job of installing upgrades is a enough of a handful in itself, running into issues beyond the normal issues one would expect does become a depressing 'Aw s*** - here we go again' situation. :)
@@flashjazzcat I guess it is all about expectations. When I expect something to be straight forward smooth and it is crap, I am frustrated too. When I know it will be an real challenge, I enjoy it. Most of all, I do enjoy your videos.
Nice👍👍This 800XL will have one happy owner. This is right up there with some of the Amiga mods I've seen. It's amazing what the Atari 8bit community has accomplished.
I'm amazed hardware is still being made for such an old computer. I had an Atari 800 XL that I used from 1985 to 1990 as a young kid almost every day, I still have it to this day but no longer seems to have any life in it. Maybe the PSU or chips have died. So many great games I enjoyed playing like Gauntlet, Raid Over Moscow, Fort Apocalypse and Ninja. 🙂
8:30 That's a travel pillow. Some people find they work great for sleeping on planes, which is probably why they call that one a "flying bear." (I'm not among those "some people," and can't sleep on a plane with or without such a pillow.)
You have infinite patience for these things ;) Just so that you know, for me one point of instability in my modified 800XL (by far not as much as this one) was actually the SRAM board, had to revert to the stock RAM in the end. And it was also highly dependent on the pairing with a particular CPU too. In any case, you did not get to run Avery's VBXE vertical alignment test in the end, did you?
I did not, unfortunately, since this is the only NTSC VBXE machine in the house at the moment (I have long intended to upgrade another 1200XL and leave it NTSC for testing purposes, but my own projects are always languishing at the bottom of the to-do list). Funny you should mention the SRAM, as I foreshadowed this in the video by speculating that it might change the characteristics of the machine, and not necessarily in a positive way. That's why I prefer to stick with stock RAM, but in this case, SRAM+O2 Fixer was advertised as the magic bullet for fixing Rapidus and SIDE3 issues. I guess I'll try removing the SRAM in part 2 and see where that goes. Thanks!
Welcome back, seeing this 800XL makes my upgrade trials and tribulations seem quite tame! :-) Hope you get on top of the issues, seems a lot of this hardware needs more development time - definitely giving off 'alpha' vibes, not even 'beta' stage yet LOL!
I always get some helpful nuggets out of your videos. I live in NTSC land and could not get my USB AKI to work on my NTSC XEGS. I also have a PAL 800xl and the AKI worked fine on that. This explains it!!! I assumed I had ruined something when I removed the ICs and added sockets to the XEGS. WOW... the time I spent testing traces...
To clarify my earlier response: it's hard to know for sure why your AKI didn't work in the XEGS, since the production firmware (which I lost in the video and couldn't get back) did allow the AKI to work in the NTSC 800XL. However, the same board revision previously didn't work in a PAL XEGS until I made modifications to the motherboard (removing two inductors on the keyboard connector and adding pullups to KR1 and KR2, IIRC). So the issue you ran into with your NTSC XEGS may not have been a firmware issue at all, but a hardware problem.
I have a SRAM module mounted between Rapidus and CPU and everything works. So you can try it. In order to reduce the height of the Rapidus tower I soldered some of the components together - the Rapidus is soldered directly into the relocator and so is the ROM ribbon cable. It makes the whole construction more robust.
Jon yet another amazing job of cramming 10 lbs of stuff into a 1 lb container, but as per usual you kept the cabling extremely organized. As for the AKI PAL vs. NTSC issue, and the interference with SIO, I quite frankly was trying to wrap my brain around why a Pokey keyboard interface would even be connected in any way to the SIO either physically or via software. As you know I have made a few designs of my own in this regard, and to speak "Pokeynese" all that's required is to connect to the Pokey Counter Bits and the KR1 and KR2 pins, none of which should influence the SIO or care about whether it's an NTSC or PAL system. Something very strange is afoot.
Thanks Michael. As for SIO interaction: the full version of the AKI v2 firmware actually allows an SIO boot from a USB stick (so Candle tells me), so I guess this explains it.
Yes - this is one of the features which had to be removed in the stripped-down firmware Candle sent me for the original boards (the firmware which has the config feature, but doesn't work on NTSC machines). Obviously since there's only one USB port, the pen drive booting and external keyboard are mutually exclusive, but it's still an interesting facility. I just received a new AKI board here, so - since I have gotten SIDE3 to work - I can now film part 2. ;)
I'll be looking forward to viewing part 2. Oh BTW, congrats on getting settled into your new home, and I hope it's in a much more peaceful neighborhood.
The 02 signals run through each Atari LSI chip and the circuitry within each degrades the signal, so that by the time it reaches the last chip, it's a complete mess, and that is why numerous expansions tend to fail. The idea of a clean clock going into each chip is a great idea and pretty much guarantees a clean signal. It also eliminates the clock being a possible cause of flakiness. Digital circuitry's ideal is a clean square wave with a 50% duty cycle, but Atari's clock is varying approximations of a degraded sine wave, and by the time it reaches the last chip, it's barely a 10% duty cycle in many cases and barely over the 74LS 2.5 volt threshold. This passed Atari's quality control, because the system worked as stock and the external interface was SIO. This bus instability is one of the reasons why Atari did away with PBI. I have been amazed that makers of new Atari PC boards haven't incorporated clean 02 signals, but instead stick with Atari's cost cutting design. One Schmidt trigger chip solves this problem and gives a clean and stable clock to all of the system chips. Edit: You know the irony of all of this, had Atari just incorporated a Schmidt trigger buffer circuit in each LSI chip (instead of just a transistor on the die), this would be a non-issue. However, that would have required a new die mask.
Yes - that's the theory, but the practice is quite a different matter. Schmidt trigger approaches are nothing new, so it's interesting to observe that things have barely improved in some senses since ICD would take your 800XL and mod it to be stable with the MIO, for example.
@@flashjazzcat Indeed, as you are attempting to interface 40+ year old technology with modern technology and something is going to complain. It's like trying to turbo charge a Ford Model T. Nevertheless, these improvements can't necessarily hurt, even without the other upgrades. Parasitic capacitance is a consideration having a centralized clock cleaning chip. The ideal improvement is having a better method of clock "cleaning" local to each chip and not a spaghetti mess of wires running to each of them. Frankly, a complete redesign of the motherboard and its clock bus as well as better chip placement is a better approach, short of completely replacing the internals with a FPGA centralized solution. When computers started to get faster and clock speeds increased, clock cleaning was mandatory. They started with square wave clocks, ditching the sine wave. Schmidt triggers were used strategically on the motherboard to buffer the clock.
@@flashjazzcat With Atari's, nothing surprises me anymore. They were both ahead of their time, at the time they came out, but also extremely flaky to remain affordable. It's almost like they designed solid systems, but Warner said cut the manufacturing price in half and consumers got the "functioning as stock" result.
Doesn’t seem unreasonable. I have so much pristine Atari kit in my loft, but I have no idea if any of it still works. All the electrolytic caps have probably dried out.
I Guess that's not much pay if that's taken you near two weeks. Like £500 a month . New Workshop/Office looking good . Dlad you and Deb's finally got 'most' of the move over now@@flashjazzcat
9:15 That's meant to be worn as a name tag. You put the back under your shirt. That way you don't have to poke holes in your shirt for traditional name tags. I've seen them with clear plastic holders so that you can put your own cards in them. I rather like them.
The inflated price of PokeyMAX and the permanently high price of Rapidus make up almost half the parts cost here. Leave them out, and this becomes a medium-price run-of-the-mill upgrade job, although it's worth remembering that the keyboard and case also needed attention on this machine. That's all part and parcel of the expense of maintaining ancient computers.
thats just overkill imo that amount of money upgrading a 8bit computer , thats just mental and the hobby is totally domain of the middle aged decent sized disposable income hobbist . no danger i can try and introduce young peeps to the joys of iold tech when all the convenience and creature comfort upgrades costas much as a decent pc . no contest with kids
Everything's relative. People who want to spend money maintaining and upgrading forty-odd year old computers are by definition not looking for a PC experience. It's certainly true that some of the upgrades are currently inflated in price (partly due to supply chain and component costs), but if someone has the disposable income to upgrade their 8-bit computer to this extent, that's up to them. These upgrades aren't aimed at nascent users keen to experience 8-bit computing for the first time, but seasoned and/or returning users who remember the 'stock' experience from decades ago and want some modern creature comforts like fast loaders, mass storage, lots of memory, clear video output and an accelerated CPU.
@@flashjazzcat i know but you can see it from my point and its across the retro landscape small upgrades cool but these uber priced upgrades are killing my love for retro computing and the kids i try and show all ask about them having sd cards/usb having hdmi usb/ps2 etc and going the raspberry pi route just dosnt give the kids the feel or experience im looking to impart on them
@@gumbi79 Bear in mind the Atari 8-bit scene is one of the smallest among retro computing communities, so this may have some bearing on the price of upgrades too. But there are still plenty of stock Ataris to be had out there, so by all means grab one and use it. There are plenty of other advocates for stock machines, just as there are plenty who enjoy the modern upgrades and are happy to spend money on them.
