[water01]

Wow these are expensive on Farnells compared to other UK sites and uncle_bob's buying list.

Farnells http://uk.farnell.com/arduino/a000005/at...duino+nano £26.82

Hobby King http://www.hobbyking.co.uk/hobbyking/sto...duct=25086 £6.44

Is there some reason for this or is it just a rip off mark up?

[uncle_bob]

The cheaper ones usually are a Chinese knock off (counterfeit), but hey, they work The Farnell ones are likely to be the real Arduino ones.

Note: The ebay etc type that come from China can take 2 - 3 weeks to arrive though.

[water01]

OK thanks.

[werk_ag]

Hi, water01

As uncle_bob said you can use the cheap chinese versions. I have always used these versions. They work well and are much cheaper.
You can find them for less than £ 4

Try these, they work:

http://www.ebay.com/itm/Mini-USB-Nano-V-...258d293eaf

http://www.ebay.com/itm/New-Mini-USB-Nan...2eca6841e2

Lately, have appeared some new versions that use a new chipset, the CH340. uncle_bob have one of these, also works, but it seems the method I use to prevent auto-reset does not work in these new versions.
Until I can test them, I don't recommned these versions. Search for the ones with the FTDI chip.

[Live_Steam_Mad]

Hi, water01

As uncle_bob said you can use the cheap chinese versions. I have always used these versions. They work well and are much cheaper.
You can find them for less than £ 4

Try these, they work:

http://www.ebay.com/itm/Mini-USB-Nano-V-...258d293eaf

http://www.ebay.com/itm/New-Mini-USB-Nan...2eca6841e2

Lately, have appeared some new versions that use a new chipset, the CH340. uncle_bob have one of these, also works, but it seems the method I use to prevent auto-reset does not work in these new versions.
Until I can test them, I don't recommned these versions. Search for the ones with the FTDI chip.

Just for future readers who stop by here, please note that the 2 Ebay auctions linked to above of the Arduino Nano compatible units, feature the Prolific PL2303 chipset. The PL2303 is an unknown quantity at this time for using with this WDPro2 project. Instead, a Nano with an FTDI chipset is recommended, just as Werk says. Also, uncle_bob has managed to get a CH340G chipset Nano to work by using a capacitor instead of resistor to prevent the Nano resetting upon connection to Cumulus, if I understand correctly. uncle_bob lists this Ebay item number here ;-

http://www.meteocercal.info/forum/Thread...d=88#pid88

I personally bought the same type as Bob did for use in my RX 4.02 board, I ordered Ebay item 171488915728 here ;- http://www.ebay.com/itm/171488915728?_tr...EBIDX%3AIT ...and we will see if it works, as I build my own WDPro2 here ;- http://www.meteocercal.info/forum/Thread...-at-WDPro2

Regards,

Alistair G.

[werk_ag]

... Instead, a Nano with an FTDI chipset is recommended, just as Werk says.

Just a correction: Due to reasons explained on this topic from 24-10-2014, I no more recommend a Nano with FTDI chipset, now I only recommend Nano with CH340G chipset.

Yeah, I think the plan is to promote the CH340G Nano after FTDIs' dummy spat.

Yes, now I only recommend arduinos with CH340G chipset.
FTDI have the right to fight piracy, but not at final consumer expenses. What they have done, in some countries is also illegal.