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mightor wrote:I would normally split them up like this:

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int foo = 0x4589
byte msb = (foo >> 8) & 0xFF;
byte lsb = foo & 0xFF;

int foo = 0x4589;
byte msb = (foo & 0xFF00) >> 8;
byte lsb = foo & 0xFF;

A little rant:
*Someone unplugged it in order to stick in a USB (none of the other ports would do, of course, even though they were all there, just begging to be used).
Then, I tried figuring it out for about an hour (and researching a bit). I decided I'd put a NumOut() and Wait() in my function, but it wouldn't display. I changed some of the variables, but the program would remain the same... almost as if it wasn't downloading.
My bloodshot eyes wandered over to the USB ports, and ...

muntoo wrote:The solution:

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int foo = 0x4589;
byte msb = (foo & 0xFF) >> 8;
byte lsb = foo & 0xFF;

muntoo wrote:First NXC Question on StackOverflow
And another question: Is a signed integer stored using one's complement or what?

The best way to do this in NXC with the opcodes available in the underlying VM is to use FlattenVar to convert any type into a string (aka byte array with a null added at the end). It results in a single VM opcode operation where any of the above options which use shifts and logical ANDs and array operations will require dozens of lines of assembly language.

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task main()
{
  int x = Random(); // 16 bit random number - could be negative
  string data;
  data = FlattenVar(x); // convert type to byte array with trailing null
  NumOut(0, LCD_LINE1, x);
  for (int i=0; i < ArrayLen(data)-1; i++)
  {
#ifdef __ENHANCED_FIRMWARE
    TextOut(0, LCD_LINE2-8*i, FormatNum("0x%2.2x", data[i]));
#else
    NumOut(0, LCD_LINE2-8*i, data[i]);
#endif
  }
  Wait(SEC_4);
}

The best way to get help with LEGO MINDSTORMS and the NXT and Not eXactly C is via the mindboards forums at http://forums.mindboards.net/

mightor wrote:The first one makes no sense:
0x4589 & 0xFF = 0x0089
0x0089 >> 8 = 0x00