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I can't seem to reproduce that. I have increased it to 250 bytes, the code (NanodeRF_multinode.ino) compiles, loads and does appear to run (though I don't have it connected to anywhere). I have not tried writing to fill the buffer.

Have you checked that your 165 bytes is actually enough, and you're not overflowing the buffer?

I've found I can extend it quite a long way 400+, there's a useful library and function that can be used, detailed here: http://arduino.cc/playground/Code/AvailableMemory to get the amount of available memory.

I use str.length() to print its length before sending to server. And it's around 135 - 148bytes having shortened all my feed idents.

if i set it to 265 the code does not even elaborate! No serial o/p at all.

Will check out free memory tomorrow

Trystan How do you recall that out of the library?
I got the same problem with my NanodeRF and sensingshield. The arduino goes "mad" if increase the packetbuffer more than 200. And there are 2 more buffers in the sketch. 50 of the HTTP header (callback) and 700 (!!) for the ethercard buffer. and all the serial communication, datatypes (a INT = 16 bit, a Byte=8bit) takes a lot of the SRAM.

My sketch will work if I disable al the serial communication that isn't needed for posting, and shrink al the datatypes to BYTE where it's possible.

But I want to know how mutch SRAM takes.. and have 2 points where I have some doubts about:

1) why does the ethercard::buffer=700 need so mutch SRAM?

2) The amount of receiving nodes at X time is also a factor to deal with. If you get many packets from Nodes you get out of SRAM very quickly! See also the posting of user "mountaindude" at http://openenergymonitor.org/emon/node/1084

"Trystan How do you recall that out of the library?"

Do you mean: "How do you install that in the library?"

Copy the first part into your editor and save it as a file named MemoryFree.h
Copy the second part into your editor and save it as a file named MemoryFree.cpp
Move both files in a directory called MemoryFree
Copy that directory into your Libraries directory.

In your sketch do like "Example sketch: "

Put at the end of loop( ) in the example nanodeRF_multinode sketch, mine reports 208 bytes free.

tnx Robert, my nanodeRF with sensingshield and one jeenode with 3 temp sensors gives me a 125 bytes free of SRAM with minimal serial print communication on it. but with full-debug communication it drops to 77 bytes. and it will create a buffer over-run with a high frequency of RF12 radio communication (receiving sensors) so this confirmed my Sram issue with my sketch.