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1  Using Arduino / Project Guidance / Re: LED Mask Help? on: Today at 02:29:27 am

You could trade money for knowledge.  For example, adafruit sells NeoPixels (individually addressable full color LEDs)...
http://www.adafruit.com/category/168
2  Using Arduino / Programming Questions / Re: Where does 93 bytes of RAM go? on: Today at 01:33:52 am

 smiley-lol
3  Using Arduino / Programming Questions / Re: Where does 93 bytes of RAM go? on: Today at 01:00:46 am
...although I can't quite see why.

Artifact of an early Libc version that only worked with words?  A Libc developer misread the documentation?  Limitation of the GCC linker?

The "linker scripts" (whatever those are) come with the toolset so, in theory, the alignment could be changed.
4  Using Arduino / Programming Questions / Re: Where does 93 bytes of RAM go? on: Today at 12:06:21 am

Ah, here we go... http://www.avrfreaks.net/comment/385590#comment-385590 ...appears the .data section is word aligned because the initial values are copied from Flash.
5  Using Arduino / Programming Questions / Re: Where does 93 bytes of RAM go? on: Today at 12:03:11 am

Yeah.  It looks like sections are aligned.  Try forcing foo into the .data section...

Code:
volatile byte foo = 13;

struct ring_buffer
{
  unsigned char buffer[64];
  volatile unsigned int head;
  volatile unsigned int tail;
};

ring_buffer bar;

void setup ()
  {
  Serial.begin (115200);
  Serial.println( foo );
  foo = 1;
  memset (&bar, 0, sizeof bar);
  }  // end of setup

void loop () { }
6  Using Arduino / Programming Questions / Re: Where does 93 bytes of RAM go? on: September 30, 2014, 11:57:08 pm
It appears to have word-aligned rx_buffer for no obvious reason.

rx_buffer may be word aligned because it is in a different section (.bss instead of .data).  Maybe SRAM sections are word aligned (though they do not need to be).
7  Community / Bar Sport / Re: Are all State Machines Finite? on: September 30, 2014, 11:41:32 pm

It has been reasonably argued that the Universe as we know it is a state machine.  It has also been argued that the Universe is infinite.  If the Universe is a state machine and the Universe is infinite than the answer to the question has to be "no".

In other words, the question is philosophical rather than computational.

Quote
Infinite State Machines

A Turing machine is such a beast.  But it is also hypothetical.

Quote
IndeterminateNumberOfStates State Machines

 smiley-grin  Before I die I must use that as a class name.
8  Using Arduino / Programming Questions / Re: Where does 93 bytes of RAM go? on: September 30, 2014, 11:28:34 pm

Did you use the code from reply #33 or #37?
9  Community / Bar Sport / Re: Are all State Machines Finite? on: September 30, 2014, 10:56:50 pm
Quote
Are all State Machines Finite?

No.
10  Using Arduino / Programming Questions / Re: Where does 93 bytes of RAM go? on: September 30, 2014, 09:43:16 pm
Maybe strings are always allocated in multiples of 2.

In SRAM, no.  I believe the answer is yes for Flash.
11  Using Arduino / Programming Questions / Re: Where does 93 bytes of RAM go? on: September 30, 2014, 08:48:28 pm

Thanks for checking.
12  Using Arduino / Project Guidance / Re: LED Mask Help? on: September 30, 2014, 08:27:55 pm

I removed your post from LEDs and Multiplexing.  On this forum, cross-posting is counter productive.  If you feel your thread is not getting a good response here let a moderator know and they will move it to another section.
13  Using Arduino / Programming Questions / Re: Where does 93 bytes of RAM go? on: September 30, 2014, 08:24:10 pm

Does the reference to __malloc_heap_start pull in some of the heap management code?
14  Using Arduino / Microcontrollers / Re: Problem uploading to t85 which has nothing do to with a PCREL error on: September 30, 2014, 06:06:32 pm
Um, this thread was supposed to be a reply in http://forum.arduino.cc/index.php?topic=116674.0
Could perhaps a nice admin move it to there?

No.  Your problem has nothing to do with that topic.
15  Using Arduino / Microcontrollers / Re: Problem uploading to t85 which has nothing do to with a PCREL error on: September 30, 2014, 04:18:57 pm

Wiring is the most likely culprit.
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