XP isn't bad, and I suspect it will be very stable just running a simple EXE file all the time. The worst-case scenario is that we'll arrive at the cabin and it will be 45 degrees, just like it's been up to now. The relay drivers are 2-second one-shots, so if the PC goes bye-bye the heat boost doesn't stick on.
John
Yes, XP is pretty good. However, when you let guests use the PC for web browsing and stuff that may no longer be the case. If you really don't have phone service up there I would use a dedicated super-simple web node. Sort of a tethered mote.
Take a look at the board pic on page 10 and the schematic on page 30, it doesn't get much simpler than this:
I've seen stuff like this for sale. Pretty cheap.
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
BSoD?
Blue might be original, but the idea itself isn't. Amiga Guru Meditations were at least a little more creative...
Speaking of Microsoft Bob... I've never used but, but read about it here:
---Joel
John, I don't know if you subscribe to Circuit Cellar, but they periodically have design contests. Right now, they have one that involves some internet connected processors,
I suspect that you could take the development kit for this, and do everything that you want pretty quickly. Just make your own intenet connected thermostat!
If you submit it, and win a prize, I want a mention... ;-)
Charlie
I'd say Xerox' PARC stuff was rather a new approach to GUIs. ;-)
I recently downloaded (BitTorrent) "The Machine that Changed the World" (five hours). The PARC episode is interesting.
Why use a Windows box? Either use a PIC or ARM based platform. They can drive relays with a transistor or two in place.
Or just get an Arduino board and an ethernet shield.
it
the
Because I already have one here, connected to the Internet, with a keyboard and a screen and a PowerBasic compiler, all working.
The Integrity brick does the basic analog and digital i/o from a comm port, and I wanted to do my own signal conditioning and relay drivers anyhow.
It's just that Windows makes a few fundamental things hard. It's not a very good platform for realtime control.
Everything's working so far. Temperatures are measuring within a few tenths of a degree C against a good thermocouple meter, with purely theoretical cal factors, no cheating. Honest.
John
That depends on your required timing resolution. Down to 1ms resolution is a piece of cake. Windows has accurate multi-media timers (mmsystem.dll) since 3.x otherwise it would suck at playing music and movies.
-- Failure does not prove something is impossible, failure simply indicates you are not using the right tools... nico@nctdevpuntnl (punt=.) --------------------------------------------------------------
You can do that with Powerbasic as well:
Look what I found:
at this page:
-- Failure does not prove something is impossible, failure simply indicates you are not using the right tools... nico@nctdevpuntnl (punt=.) --------------------------------------------------------------
Thanks... I'll have to look into that. The 'readme' file is just some babbling about revs, so, as often is the case, the only documentation is the code itself. I hate when people do that.
I have the whole thing working:
ftp://jjlarkin.lmi.net/CABIN.TXT
I've just got to hook up the inside and outside RTDs. The inside one is faked with a 1K resistor for now. Gotta get out the Makita hammer drill.
If I upload a command file to the ftp site, my program parses it and turns the heat on for some specified number of hours.
I wound up using two PowerBasic programs, one the controller and a separate program just to up/down load the files to/from the ftp site. They run asynchronously.
I'll just put them into the windows startup folder for now, and see how the thing works.
Then I can ask Mo for my next project.
John
Having lived in heavy freeze areas most of my life, be careful here. A couple of degrees may not be enough. Think of the temperature gradient in the walls (and cabinets). I've seen pipes freeze when the inside temperature was ~70F. A lot more will get it if the inside temperature is only a "few degrees C".
Yeah, it does take time. Here, they don't believe in frost-free silcocks and I'm sure they aren't anal about insulation either. I've shut off all the outside water[*] and opened the silcocks. I have a "boot" over one of them but the others are in rough brick walls so it's difficult to get them to fit.
[*] the water manifold is one of the few advantages of PEX plumbing.
What, no flash-player logo, music, and all that?
You might want to consider entering an estimated arrival time instead and let the local host calculate how many hours to give the furnace, based on how cold it really is up there. Propane is quite pricey.
I never, ever do that :-)
-- Regards, Joerg http://www.analogconsultants.com/ "gmail" domain blocked because of excessive spam. Use another domain or send PM.
To keep water from freezing in pipes, you use an insulated pipe run, and the way to stop it from freezing is NOT to cut off the water as that will insure that it will freeze, unless you also EMPTY the pipe run.
It is easier, though slightly more costly to let a slow trickle out in the barn as the movement of water in the pipe will prevent freezing.
On a sunny day (Thu, 31 Dec 2009 12:54:28 -0600) it happened krw wrote in :
Last year it did only freeze for one day, and I did not bother.. This year we had -10 °C already, and -12 °C predicted for next week. And snow. I had the water off, but now, with new years fireworks, had it defrosted and on again (was just above zero today), so I can connect the fire hose outside in case some fireworks land on my place... Tomorrow I will shut the outside water off again, it is then about -1°C. Life goes on...
We leave the heat on at 45F and drain the pipes when we leave. There's a shutoff/drain valve in the laundry room. The primary function of this project is to let us turn the heat on before we leave home, so it will be warm when we get there. A bonus function is that we can know if the heater ever fails, and call somebody to go there and plug in some electrics maybe.
We're 180 miles away!
John
We'll just send it the message "turn on the heat for six hours" a bit before we leave. It's natural gas, not so expensive.
Oh. Why didn't I think of that?
John
I informed SWMBO that my Winter project was the unfinished room over the garage. Insulation isn't fun anytime but a lot better when it's
30F than when it's >100F. No cookie jar projects for a while. OTOH, we just found a leak in a wall between the pantry and refrigerator. I suspect the builder stuck a screw through the PVC drain pipe from the upstairs bathroom. :-(On a sunny day (Thu, 31 Dec 2009 14:30:19 -0800) it happened John Larkin wrote in :
Electric controlled valves?
Gotta do that here sometime.
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