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You can use a serial connection between your emonTx and RPi, and with your RPi on the end of your network, you look to be home and dry. I think you were looking for this: http://openenergymonitor.org/emon/node/3872

Robin's Mk2 doesn't monitor, but MartinR's PLL does (though I think you might need to use the emonTx V2 to have easy access to enough IO). AFAIK, nobody has yet ported MartinR's PLL to the emonTx V3).

Generally the sensor node (emonTx) transmits via 433MHz or 868MHz to a base station which sends the data on to a server running emoncms.

The most common usage currently is for the base station to be a RFM12Pi board that plugs in to a Raspberry Pi.

The scripts that run on the Pi can easily be configured to send data to any emoncms server i.e. to your windows server.  There's an install guide to running emoncms on WAMP.

The RaspberryPi has an ethernet port so no wifi needed.

wow! thanks for very fast replies.

I think I understand all  that ? so I would only need 3 wires to interface to the Rpi and then network to my pc .

I read the links to the PLL  , so that uses the emonTx V2 to Both gather the data and control the triac and also sends that info via the serial connection to the RPi  .

If I have understood that properly that's great thanks.

oh I see the shop only has the emonTx V3 is that ok?

Mike

Ah on re-readingRobert's post I see the V3 might be no good at the moment.

"AFAIK, nobody has yet ported MartinR's PLL to the emonTx V3)."

I wouldn't feel comfortable Porting it myself as I don't even know what language is used yet ! Must Check that lol

I don't think it would be too difficult to use v3, the main differences are pin numbers which are very easy to change see.http://openenergymonitor.org/emon/node/3815 it has been done, although nobody has published their v3 version which is probably what Robert meant by ported, 

You would need to upload the sketch to the v3 even if it was readily available and to do that you will have everything you need to change pin numbers etc and you'll get lots of help here on the forum.

All the sketches are arduino based http://arduino.cc/en/Reference/HomePage.

Paul

Thanks Paul

My concern with the V3 is it needs a different library (RFu_JeeLIb) and while MartinR's PLL uses low-level calls, and I don't know exactly what the difference between RFu_JeeLIb and JeeLIb is.  We do know that if JeeLib is used on the V3, it enters a reset loop that it cannot easily be got out of.

The V2 PCB is still available, so it would be possible, though difficult and expensive, to assemble a V2 by sourcing the components yourself.

I didn't think Martin used JeeLib, or is RFu_jeeLib required regardless ?

Not that there's anything wrong with using v2 (that's what I have) just nice to have options plus the v3 is nicely cased :-)

difficult and expensive two words I hate !

shiny--- nice !    :)

Looks like I will need lot's of help

thanks

What I was trying to say, Paul, is I don't know what the mechanism is inside JeeLib that causes the problem. If Martin is doing the same thing even though he doesn't use Jeelib (and I stress I don't know whether he is or he isn't), then I foresee trouble. I'm flagging a warning, that's all. I wouldn't want an inexperienced user to end up with a locked-up emonTx.

Solid advice as always Robert, My comments were meant as a reassurance that help was on hand if Mike wanted other options. I have now read up a little on this issue https://github.com/openenergymonitor/RFu_jeelib/blob/master/README.md and would agree that the "eternal loop" should be absolutely avoided,

But on a brighter note it would appear to only effect RFu v1.1 and although not guaranteed I would of thought these would no longer be available from the shop as at least v1.3 is available now. (maybe ask the shop to check rev before sending?)

Although having thought about his application some more, if Mike was unlucky enough to land a v1.1, all the RFM code could be stripped from the sketch altogether as he is planning a serial connection, that's if he even has an rfm12b fitted.

Paul

In the first instance I would not want or need  the RFM12B as I would definitely connect by serial cable.

If I added one at a later date I would assume I will have gained more knowledge and would ask anyway.

My knowledge at this point is hovering around zero.

So what do you think, should I go ahead and buy the Rpi and the emonTx v3?

I usually find I don't really learn much until I start getting stuck in.

On the other hand I don't want to start out with the wrong setup.

It's going to be a long learning curve for me and is the software that looks the most difficult for me to get to grips with.

thanks for your help it is much appreciated and I would be very hesitant to go ahead without it!

Mike

Hi again and sorry to pester!

This is probably a stupid question ;) but is there any reason why I cant skip using a Pi as a server and connect directly from the emonTx V3 to my PC serial port?

thanks

Is your serial port RS232? You'll need a hardware interface, and you'll need to get/write software to handle the protocol. Given those, it should be possible.

Well the PC hasn't got a rs232 port as such but I can build the interface and connect to usb.

I've never done it but I would think it should be simple enough.

I can write the software ok. I will need to know the data format of course but i assume the info is on this site somewhere?

thanks Robert

In that case, why not use the USB/FTDI interface which I presume you have, a programmer, and write everything to the Serial port?

yes that's what i intended.

I haven't got the usb/FDTI interface yet it seems I will have to order it from the US as I can't find one in the UK.

I assume by "Programmer" you mean the software from FTDI ?

No, I meant this when I wrote "programmer/FTDI interface". I think Wales is still in the UK ;-)

I've never tried this, I suspect you'll need a USB Library for whatever language you will use, or it may be that the SILabs drivers, which you need if you're using the Arduino IDE and Windows or OSX as your OS, look like a standard serial interface. Where to get those is on the pages about installing the Arduino IDE.

Lol I never thought it would be sold here! it didn't turn up on several googles i did.

I believe that the drivers make it look like a standard I/O port on the PC

I think I have it all worked out now, I'm sure I'll run into problems but hopefully not too hard to overcome.

So Might order today!

Thank you for your patience.

I'll try not ask too many silly questions when I run into trouble. :)