[cctalk] Re: Computer of Thesus (was: Re: Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man)

In a lot of ways it's entirely contextual, or a matter of practicality. If the goal is to just get the original operator/software experience, then emulators should do the trick. If it's about the original feel of the hardware, with all its limitations and warts, then stock hardware is the way to go. For components that fail and are hard to replace, then FPGAs are cool, and it's fun to see how far they can be tweaked using modern hardware and design sensibilities. For DECVax stuff, I just use an emulator on a pi because anything larger than the smallest VAXen are way too power and space consumptive to be at all practical. I used to have a VAXStation 2000 that might be reasonable to keep powered up 24/7, but other than that and maybe some of the desktop VAXen it's just silly to keep them running unless you're a well-funded museum willing to buy carbon offsets. For my HP 9000 stuff, it's all straight original hardware, although I'm diskless and just do netbooting of NetBSD off a PC. My Tektronix 4132 is still running on its original 40mb hard disk. I have a few fully stock Atari 800s, and one I'm in the process of fully maxing out with modern upgrades, because it's fun to see how far the machine can be taken while maintaining the original hardware. But I like to keep a fully stock machine around as well. Right now, I'm going back and forth on an IMSAI I am restoring. Part of me wants to do as slavishly accurate a restoration as I can, but the another part insists that there really is no such thing, really, as the whole culture around S100 was about taking the bus and extending it in a myriad of ways. I'll probably fall somewhere in the middle, but if I could ever find a CCS Z80 main board I would probably switch to that and put the original IMSAI 8080 MPU board into storage. I had a CCS machine back in the day and just found that to be really solid hardware with a good onboard monitor for debugging. BTW - if anyone has an IMSAI MIO board they are with (or a CCS z80 MPU board), please contact me! Replacing "doomed to fail" components like hard disks, or even potential time bombs like capacitors & batteries just makes sense. But when something becomes way too far afield from the original specs, it does kind of defeat the purpose, from my point of view. I view it as akin to classic car restoration vs hot rodding. They're both different perspectives on the same machinery, and there's value & intersections between both sides of the community from which each side can benefit. -mike ________________________________ From: Jim Brain via cctalk <cctalk(a)classiccmp.org> Sent: Monday, January 23, 2023 8:37 AM To: cctalk(a)classiccmp.org <cctalk(a)classiccmp.org> Cc: Jim Brain <brain(a)jbrain.com> Subject: [cctalk] Computer of Thesus (was: Re: Re: Computer Museum uses GreaseWeazle to help exonerate Maryland Man) On 1/23/2023 10:17 AM, Chris Zach via cctalk wrote: Though the comments started with an absolute (replacing all drives with Goteks), I assume many of us take a more pragmatic approach. As such, I do take a bit of issue with the "where do you stop" concern raised by another poster. I have all 3 here. * I have emulators for many of the machines I own, because often, answering a question can be best/fastest done that way * I have "need to get things done on this" machines, where problematic components are replaced by contemporary equivalents. I know I'm a "young un" on this list of Mini computer owners, but al most all of my daily driver home computers have their floppy drives replaced by SD card or USB equivalents. Because, when I want to enjoy firing up an app or game, I want to enjoy the game/app, not spend an hour/day/week diagnosing and fixing the system. I also use these to demonstrate the units for interested visitors, and these are the machines I take to show to demo and such * I have all stock machines, because, sometimes, only the original will do. Validating specific behavior for emulator writers, checking failure modes on certain apps, understanding actual latency/delays associated with original equipment, etc. These units are used for even the mundane efforts of determining PCB sizes or heights for folks who wish to build add-ons and such. I can't imagine I am the only one of the list with this setup (though I do understand having a daily driver PDP 11 and an all stock PDP 11 might be un-realistic, and so that owner has to make the decision on how to keep the machine configured.) But, for all the smaller units, I must be in a larger community who does this. So, while I don't have the same goal as the OP in replacing all drives with Goteks, I honestly do have that configured already for all my daily/weekly use machines. I lost no existential sleep over doing that. In the spirit of the original thought, though, where I find myself scratching my head are the folks who have replaced every IC on their vintage system with an aftermarket FPGA "equivalent" (loosely used here). The resulting board, with all of the expensive FPGA devices, costs much more than obtaining a second stock unit, and when every IC has been replaced with FPGA, I am not sure I see the value over just obtaining an FPGA-based design where all of the IC functionality has been aggregated into 1 larger HDL-based device. The "keyhole" nature of replacing each individual IC seems expensive, prone to issues, and still relies on constraints of the original motherboard and/or mobo design. But, I smile and nod when I see them at shows, since it must make sense to the owner, and that's how they enjoy the hobby. Jim