On 11 Jan 2024 at 22:06, Eric Auer via Freedos-user wrote: > > Hi Anton, > > > The machines are indeed physical with custom made ISA Bus controller > > cards, built on prototype board, and only 4 were made, 2 in production > > That sounds exciting! > > > plan is to eventually replace ... with something more ubiquitous. > > Looking at other forums, people do impressive things combining old > and new hardware. For example there are tiny modern microcontroller > based extension cards for old PC, emulating all sorts of classic > boards, people convert from TV to HDMI using DSP based boards and > DOS expert RayeR is working on a way to connect classic ISA sound > cards to modern mainboards through the LPC bus on the TPM header! > > For more general purpose things, Raspberry Pi style computers can > be a good option, natively running Linux, sometimes other operating > systems, or emulators for retro operating systems inside Linux, > while at the same time offering a variety of GPIO and bus systems > suitable for different control projects. > > Have a good evening, too! Eric >
This is my long-term "food for thought". Keep the old (often DOS-based) system going, especially if you have docs and source code, vs. rebuild from scratch using %your_favourite_contemporary_technology% . On my job, selling hardware to people who have a longer planning horizon / end up being themselves long in the tooth, I've met several individuals and systems that are at the heart of some company's business "in real life", and are difficult to replace. The living of a manufacturer may depend on such one-of-a-kind system. The general idea may be: try to avoid stuff that's obscure. Whenever possible, i.e. when doing an overhaul, you need to replace an obscure solution with something more manageable in the long term = open, modular, better structured, more future-proof, with a long/infinite end of sale. Makes me wonder what that would be. DOS and ISA-based hardware have been around for what - 40 years? You can still purchase a new x86 computer to run DOS, with ISA slots, from companies like Advantech and ICOP (you will possibly have to combine parts sold by the these two, in a PICMG setup). If you have the source code, and there are people around who grok it... that's a relatively fine situation, innit? :-) Replace such an old solution with something that's based on Linux and e.g. the RPi. Note that the RPi is a proprietary platform. Yes it's been around for a decade or so. But: are there any clones / is there offspring? There are certainly work-alikes and friends, all of them with a lower market share, none of them binary compatible. This is only future-proof as long as new pieces of the hardware are available, and the "ecosystem" around = the build environment, installationg media, perhaps a card reader for the boot disk (microSD) and whatnot. Speaking of x86, for instance, by now physical 3.5" floppy drives are a problem, and parallel IDE isn't easily around either, anymore. CD's are getting out of fashion, to the point of becoming nearly extinct... So: whatever platform of SW and HW you choose for your future-proof system, you'd better purchase a crate of spare parts while they are available :-) and make a thorough data backup and precautions, that will allow you to keep the "build environment" or at least the "deployment aids" alive into the future. People building things on Windows and PCI a decade ago are facing these issues right now! Compared to the old days of ISA and DOS, moral longevity of both hardware and software has *shortened*, and there is a tendency to make all the stuff more proprietary, more turn-key, more "vertically integrated" i.e. your special PCI(-e) device is no use whatsoever without a signed driver for your particular current OS version, which won't boot on a new computer two years down the road (as there won't be drivers for the disk controller for your current OS version). There are "temporal windows of backward compatibility", but typically not very long, factual compatibility is always subject to practical testing = never certain beforehand. It's actually getting difficult to install the same binary-identical OS version from scratch again a few years down the road, etc. Emulators and hypervizors are all fine, but tend to separate your OS instance from bare metal. We don't even need to speak modern OS versioning and compatibility maintenance. In the plant process control, there are parts such as analog interface adaptation converters (AKA "barriers") = amps, isolators, level-shifters, filters. 20-30 years ago there were fine parts in this category that in the meantime have been phased out without a direct replacement - as to the function, not to mention pin-compatibility. Now... there are systems whose functionality or "control task" is relatively simple, and attainable by various means. For many purposes, any PLC on the market, from any major brand, will do the job. There's even a IEC-standard high-level programming language for PLC's. And then there are "assignments" that you just don't cobble together out of anything currently on the market: - real-time control in a tight loop with a fast sampling rate / low latency - special interfacing hardware needed, beyond the bread and butter formats of the industry - special requirements on software / logic, which cannot be built out of the name-brand "legoes" - any system that's sufficiently complex / large, to become a dependency nightmare (among its many internal modules, and at the outside interfaces) - or maybe you do find a brand that suits your needs, but you'd end up in a tight vendor lock-in, over a niche product (that has a limited customer base), with a large company who has a turbulent shareholder structure, a sprawling marketing dept., is run by bean-counters etc. When considering a thorough overhaul, going all the development cycle from scratch, vs. pulling off a small hack to replace a peripheral card, to keep the existing solution going, ... guess what I would vote for. DOS is a stable environment. It won't version-creep on you. As long as you have suitable hardware, and your date/time data types don't run out, you're fine :-) Linux is neat, in that you have the source code for everything, and seems just about unstoppable by now as a "living software project". But even maintaining an in-kernel driver for your peripherals is continuous work, if you need to keep updating the kernel to stay compatible with recent motherboard hardware. Apart from the constant progress in the "internal kernel API", also the vanilla kernel build system keeps raising the bar against you rolling your own driver out of tree (even if still relatively marginally). DOS is probably less laborious to keep going, as long as you can get suitable hardware to run it. You always have a choice, what to base your system on. In my opinion, getting focused on a particular MCU model and OS version currently available, for a custom project... doesn't sound very future-proof :-( A low-tech open architecture, even if "precambrian", may actually sound appealing. Maybe the topic boils down to: if you are an organization with special needs, can you afford to maintain the critical in-house expertise, through decades, to keep your custom special designs workable? I have an overall sorry feeling that the modern-day evolution of software happens at layers ever more detached from the hardware and brings ever more bloat, obscurity, vendor-lock and dependency hell... It's probably indicative of me getting old :-) Frank _______________________________________________ Freedos-user mailing list Freedos-user@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/freedos-user
