PDA

View Full Version : An anemometer to ethernet question



Neill
10-03-2008, 02:24 AM
My first posting so sorry if I am breaking any unwritten forum rules.

This year I had solar panels installed on my house and wrote some code to get the actual values on to the web every 5minutes- www.hogarth.de/heating
Now the winter is coming and I am thinking about my next project.

The plan is to constantly measure the wind and display 5 minute average max and min every 5 minutes. This should help me decide if a wind generator can help with the heating.

The anemometer I can build myself and it will deliver one pulse per turn (reed contact).
From there on I am in to new territory and would really appreciate any help, pointers or advice to start me on my way.

I would have thought that an idea could be:
Connect the anemometer to the basic stamp
Use some sort of ethernet / serial adapter to connect the basic stamp to the network.
count the pulses with the basic stamp.
Every 5 minutes work out the average, max and min and save them on the basic stamp.
have my Linux PC that „harvests“ the solar data come along every 5 minutes and also collect the wind data.

from then on I am back on known terrain.

So my questions:
Is the concept sensible?
If so which basic stamp?
Any suggestions for a Ethernet/Serial converter?
Any better ideas.

Thank you in advance for any and all help.
Greetings from the sunny Alps!

Neill

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
www.Hogarth.de
Life is not a practice

Phil Pilgrim (PhiPi)
10-03-2008, 02:51 AM
Since you're using a PC anyway, an ethernet connection is an unnecessary complication. It would be simpler just to bring the two switch-closure leads from the anemometer into the house to the BASIC Stamp, and connect the Stamp (BS2 would work fine) to your PC via a serial connection (i.e. RS232 direct or via a USB converter). A script (Perl, etc.) on the PC can then harvest the data via the serial port and possibly act as a CGI backend for whatever server software you might have running.
Be sure to use lightning protection!

-Phil

Post Edited (Phil Pilgrim (PhiPi)) : 10/2/2008 7:56:24 PM GMT

Neill
10-03-2008, 03:15 AM
Thank you for the quick answer but the sensor will be far up the garden and connected by WLAN. Sorry! Forgot that bit. Or maybe there is a better radio connection legal in Germany?

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
www.Hogarth.de
Life is not a practice

Phil Pilgrim (PhiPi)
10-03-2008, 04:37 AM
Well, that complicates things. If it were here in the States, I'd use an XBee-Pro module on the Stamp, and another at the PC, connected to a serial port. But I don't know if these modules are legal in Germany.

-Phil

Franklin
10-03-2008, 08:04 AM
For starters this might be something you could use. www.lantronix.com/device-networking/embedded-device-servers/?tab=1 (http://www.lantronix.com/device-networking/embedded-device-servers/?tab=1)

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
- Stephen

Neill
10-03-2008, 07:20 PM
Thank you for the information.
Sorry that my last answer was a bit "short" but I was working on a mobile phone with no real keyboard.
My garden slopes up to the top of a hill and that is where I want to place my sensor. WLAN just looked a good way to go before I begin laying cables.

Stephen: The Lantronix stuff looks like it could be a help. Thanks for that.

And every one else: I assume that the lack of negative comments assumes that the Basic Stamp will do what I want. Thanks.
Can any one suggest which basic stamp would be suitable for something like this?

Thanks everyone.

Neill

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
www.Hogarth.de
Life is not a practice

Franklin
10-03-2008, 10:07 PM
One of the 'P' versions will give you more ways to communicate with your sensors since they have I2C and Dallas 1-wire built in to the language.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
- Stephen

CannibalRobotics
10-03-2008, 11:22 PM
You could use the Parallax 433MHz Lynx radio transmitter pair. Hook the data line on the transmitter up to your sensor. Your receiver in the house could output into the Basic stamp. That way you don't have allot of expensive hardware sitting up on a pole.

Neill
10-04-2008, 02:35 PM
Once again, thank you for the advice.
It is always best to ask lots of opinions before starting.
As soon as you mentioned this I thought - "here is a great idea".
Obviously a minimum of complexity (and power consumption) on a pole is a good idea.
And then I can connect the stamp straight in to my PC.

I assume that (as a beginner) the way to go is to get my application working on my desk (stamp directly connected to PC) and then add in the RF link later.

Thank you for taking the time to advise me.

Neill

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
www.Hogarth.de
Life is not a practice

Jonathan
10-04-2008, 09:09 PM
Neil,

One thing about the Parallax RF units is that they have no built in error checking for data corruption. This is not a knock on them, they are great and I have used them many times. But, it does mean that you need to check for valid data. Some RF modules, like the XBEE or EB500 have all of that built in.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
www.madlabs.info (http://www.madlabs.info) - Home of the Hydrogen Fuel Cell Robot

Neill
10-05-2008, 02:48 AM
Thank you Jonathan!

I assume, once again that once I have a working application with PC to stamp then I add two of these in the connection to extend it?
Correct?

You said you had experience with both modules. Will the XBEE really give 30 meters?

Thanks!
Neill

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
www.Hogarth.de
Life is not a practice

Jonathan
10-05-2008, 02:58 AM
I actually haven't used the XBEE, just the EB500. But, as I understand it, they do give the advertised range. As I haven't used the XBEE, I don't know if it provides a RS232 output or not, if not you may need a MAX232 chip to send the data to the PC. The Stamp uses 5v TTL logic levels and the PC uses RS232 12V logic levels.

And yes, get it working with the PC and then move to RF. Let us know which units you end up with, and if needed we can help with error checking of data.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
www.madlabs.info (http://www.madlabs.info) - Home of the Hydrogen Fuel Cell Robot

Franklin
10-05-2008, 03:52 AM
If you go with xbee I think Sparkfun sells a USB board that you plug your xbee into and connect to the pc. Someone here did also but I've not heard much about it lately, I'm sure if it is still available you will hear about it soon.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
- Stephen

lenswerks
10-05-2008, 11:52 AM
Neill XBee would seem to be a good and easy to use choice. I would recommend the XB24-ACI-001. The XB24 series have a 300 foot range - The XP24 power requirement is ~50mA·. Only·the XB24·Function Set will allow you to do I/O line passing, either digial I/O or ADC - so what happens on the remote XBee pin(s) happens on the base unit pin(s). The part number is XB-24-XXX-001, XXX specifies antenna choice.

If you need extended range you could use more that two or another modem choice, but you won't be able to use the line passing functions unless using the "XP24".

Get a copy of the X-CTU interface from digi.com, go under Modem Configuration | Modem =XP24 and take a look at the Function Set features and this page http://www.digi.com/support/kbase/kbaseresultdetl.jsp?kb=188

I'm using these to pass back PIR sensor·output to a base XBee connected to my PINK connected BS2p-40.

Donnie