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Commodore PC Still Controls Heat and A/C At 19 Michigan Public Schools
jmulvey writes: Think your SCADA systems are outdated? Environmental monitoring at 19 Grand Rapids Public Schools are still controlled by a Commodore Amiga. Programmed by a High School student in the 1980s, the system has been running 24/7 for decades. A replacement has been budgeted by the school system, estimated cost: Between $1.5 and 2 million. How much is your old Commodore Amiga worth?
It's amazing how successfully IBM/MIcrosoft won the war over the word "PC": now only Windows computers can be called personal computers.
It's equally amazing how meaningless that victory actually is.
"First they came for the slanderers and i said nothing."
If they are only having problems with the hardware, why not just put an Amiga emulator on a new computer?
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I love that a 30 year old computer is doing the job just fine.
I love that a kid wrote the code ages ago, and presumably it has never even been patched.
I love that the Amiga was so damn rock solid that it has not had an emergent failure in 30 years.
I love that it uses walkie talkie beeps as a protocol
I love that somehow it is going to cost 2 million dollars to reproduce something a kid did in his spare time, presumably simply for the privilege of getting to play with a $1300 dollar computer.
Environmental control and monitoring becomes complicated when you're considering large buildings.
And yet a high-school student from the 1980's was able to engineer a system with off the shelf computers and a little ingenuity. And managed to build a system that has lasted for 25 years.
Pi plus some student programmers - should be done for $1500. Which begs the question - if it still works, why replace it?
In my old house, there was an analog thermostat.
This thermostat came with the house, probably cost $20, and worked just fine.
Me, being the foolhardy spendthrift I am, dropped TEN TIMES that on a fancy-shmancy programmable thing with all sorts of stupid, complicated bits inside.
As it turns out, my previous model--while perfectly functional--was really quite inefficient, and the new unit had pretty much paid for itself within a few weeks.
Doing things properly can save tons of money.
Obliteracy: Words with explosions
My seventh grade Apple II teacher in 1983 called my Commodore VIC-20 a toy in front of the class. That's when I learned that I came from a "poor" family because we couldn't afford an Apple II. My parents got me a Commodore 64 the following year. I went through three C64 in the next ten years. My first PC after college was literally an old IBM PC/AT (286) that a roommate brought home work in 1995.
And what do you do if a part dies? Where are you going to get parts for something that has not been manufactured for 20+ years?
eBay, there is a TON of that stuff out there... the prices are cheap as well...
When the Amiga system originally went in it was controlling well over 100 buildings throughout the district, including the entire GRCC campus at the time. The Amiga replaced the head-end of the system, which was experiencing expensive hardware failures every year ... and you couldn't get parts for that mini-computer on e-bay. It is essentially acting as a huge database (schedules, configurations, control programs, history, etc.), system manager, and monitoring system ("head-end") for the remaining 19 buildings HVAC systems. If the Amiga goes down, the buildings will continue to operate using the configurations last received, with most of the individual device controls being able to be manually overridden inside each building, albeit with less energy efficiency. What you will loose is the ability to change schedules/custom control code/configurations and the ability to centrally monitor the performance of the buildings.
Each building has one or more local control systems, and those systems communicate back to the central head-end over radio-modem (there was no district-wide network back then). Schedule and other control changes are sent to the buildings and alerts/reports are sent back. That old equipment in the buildings, even older than the Amiga, is what dictates the radio communications link. They incorporate specific protocols for keying up the radio that are not directly compatible with a newer serial to Ethernet type device that would seem like a logical replacement.
The control systems themselves gather temperatures, both inside and outside the building, look at trends and do predictive control of the equipment to accomodate scheduled use of various areas of each building. For the day, this was very advanced building control and offered significant energy savings, as well as comfort in the buildings.
Over time, as buildings have been updated, sold or replaced, the local controls withing those buildings have been replaced with newer/more modern controls that communicate with newer central control systems. Replacing these controls that are local to the buildings is what is responsible for the majority of the cost I would say.
As far as the Amiga system itself, I believe most of the components are still the original. The hard drive may have failed twice over the years, requiring a rebuild from backups. They did pick up or have donated a few Amiga systems to use as parts as needed, but the system has proven to be very resilient. Obviously, Monitors, Keyboards and Mice can only take so much use without needing to be replaced. Without this, the system likely would have become inoperable and unservicable many years ago, or been incredibly expensive to keep running.
From a technical stand point, the Amiga was selected because at the time it was the only "Personal Computer" (PC) that had a true pre-emptive multi-taskng operating system. It needed to be able to handle multiple processes simultaneously, including interfacing with the systems, maintaining settings in the database, monitoring the system as well as support for both local and remote access to the system simultaneously. Basically, its capabilities fit the need. While for nostalgia reasons I would hate to see it go, it has been 30 years and I think the system has done its job. Replacing a building's control system doesn't happen overnight, and when you are talking 19 buildings with ancient (yes I am calling myself ancient I guess) control systems, it is going to take money and time. The payback in energy savings, comfort and safe control of the buildings though I think justifies the cost.
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How the bloody hell did you go through *three* of them? I only had one, and it lasted until I gave it away many years later.
You could murder someone with a Commodore 64 after fishing it out of a swimming pool filled with beer and it would still run fine.
>a classmate posting something questioning the pre-emptive multitasking capabilities of AmigaOS
Yes. The Amiga ran on a 68000. The 68000 didn't support instruction restart. So you couldn't properly do preemptive multitasking with it. It needed the applications to cooperate with the interruptions. So an application could undermine the preemption. The 68010 fixed this problem. There were also unix based 68000 workstations that had two 68000s, one running a clock cycle behind the other, so the state of the CPU could be rewound and the instruction restarted when necessary.
I should use this sig to advertise my book ISBN-13 : 978-1501515132.
o one referred to "Personal Computer" at the time with uppercase letters except when it was part of the computer's name (upper case makes it a proper noun). As an acronym, I don't recall "PC" ever being used to describe the generic class of microcomputers.
I don't know where you lived, but we used "PC" that way consistently. No one had a IBM PC in high school: our PCs were C64s, Amigas, Ataris, and the one lucky guy who could afford a Mac. We never needed a word for "IBM PC clone" as non of us had one.
Maybe it's regional, like the whole "what kind of coke would you like" thing.
Socialism: a lie told by totalitarians and believed by fools.
Been there, done that. You're invisible if your stuff doesn't break. Nobody even knows your name. Tell someone what you did and they only see that you worked on outdated technology with no relevance to current systems.