greenhouse temperature measurement via x10 ?

[Nick Cross]

Sorry if this is mentioned in the FAQ, or has been asked before but my ISP
doesn't store many messages from this group. =(

There seems to be a HUGE amount of information out on the web, and I've
spent quite a few hours tonight looking at it. But I'm getting lazy...

I'm trying to find out whether it will be fairly simple to use an existing
RS-232 serial (DB9) temperature probe to measure temperature in my
greenhouse, before I dive in and spend $$$/£££ on a cm11u/cm12u and some
other cool x10 kit. My greenhouse is 300ft from my house, but is mains
cabled (finished that this morning). =)

Should I be looking at a xm10u Two-way PLC Interface?

I don't mind a bit of programming, in fact this will most likely run on my
linux webserver so i can keep a check on it from work.

If anyone could point me to theirs or someone elses project that has done
similiar that would be great. Otherwise its back to programming my Husky
fex21 just to read the serial probe, with a wireless NIC in it, and leaving
it under a big plant pot, and no x10 =(

cheers,

Nick.

[Chuck Y]

Nick Cross wrote: Sorry if this is mentioned in the FAQ, or has been asked before but
my ISP doesn't store many messages from this group. =( There seems to be a HUGE amount of information out on the web, and I've spent quite a few hours tonight looking at it. But I'm getting lazy... I'm trying to find out whether it will be fairly simple to use an
existing RS-232 serial (DB9) temperature probe to measure temperature in my greenhouse, before I dive in and spend $$$/£££ on a cm11u/cm12u and some other cool x10 kit. My greenhouse is 300ft from my house, but is mains cabled (finished that this morning). =)


RS-232 works fine up to around 900 feet.
Analog will drop off at longer distances (though
you CAN calibrate).

I'd toss it in the greenhouse and run a CAT5 with the 232
on it back to the computer.

You MIGHT look at some of the single chip computers like a BASIC
stamp or many many others and have THAT in the greenhouse.
That way you can have it read many sensors and trigger events.
(when waist high temp > T and it's colder outside than inside,
then turn on motor to open window, or a fan if it's cooler down
low than up high by too much.).

I wrote a greenhouse control in FORTH once upon a time, long long
ago. Motor's were best handled when the computer sends a trigger
event that causes a circuit to open or close. (presume the computer
will crash when the motor is on and design around that).

There are many many many boards out there that can read/write analog
and digital and haev 1-2 serial ports to talk to the main computer
and perhaps antoher device.

Oh, I also like the LCD+. Many analog inputs, keypad inputs, relay
outputs, LCD. serial control. The pics don't show that it's around
3" deep.

http://www.basicx.com/Products/LCD+/LCD+overview.htm


I won't order from them online cause their "secure server" uses
lightweight SSL (56 bit rather than 128bit). And I don't really
trust their server - it's way too wide open for me to put data on.

The basicX MCPUs look sorta interesting. Program in basic and it's
got a wad of IO.

Choices abound.

[awm]

Nick Cross wrote: Sorry if this is mentioned in the FAQ, or has been asked before but my ISP doesn't store many messages from this group. =( There seems to be a HUGE amount of information out on the web, and I've spent quite a few hours tonight looking at it. But I'm getting lazy... I'm trying to find out whether it will be fairly simple to use an existing RS-232 serial (DB9) temperature probe to measure temperature in my greenhouse, before I dive in and spend $$$/£££ on a cm11u/cm12u and some other cool x10 kit. My greenhouse is 300ft from my house, but is mains cabled (finished that this morning). =) Should I be looking at a xm10u Two-way PLC Interface? I don't mind a bit of programming, in fact this will most likely run on my linux webserver so i can keep a check on it from work. If anyone could point me to theirs or someone elses project that has done similiar that would be great. Otherwise its back to programming my Husky fex21 just to read the serial probe, with a wireless NIC in it, and leaving it under a big plant pot, and no x10 =( cheers, Nick.
Best way of doing it is to use Dallas Semiconductor DS18S20 sensors
very cheap accurate and easy to wire up. Off the shelf budget priced kit
are avialable from this url http://quasarelectronics.com/3145.htm
see also http://autom8it.com/

These urls might also be of interest
http://www.picotech.com/data.html
http://www.phanderson.com/