If this is the function you are using you cannot just return ubuffer and use it as it is only valid in the function. Outside of the function the value is not defined and will probably be corrupted. You need to add the word static in front of the variable declaration for this to work.

I really also think that OP needs to clarify if he needs to convert the numbers to a string or if the value is just passed in what is effectively a byte buffer.

The easiest way is to cast the value when you call the function, provided you know the library is simply expecting a buffer with the value and not actually chars. Cast by putting the desired type in front of the variable name.

Code:

myFunction((char *) myVarName)

I think the typedef is the issue. You need to declare it in a header file for it to work. Seemed to fix a similar issue I had in the past.

Millis can't be reset. What you need to do is remember when your time period started by storing the value of millis at the time and then working out time elapsed by subtracting current value from the stored value.  This is a pretty common technique with timing stuff on computers.

You are sending many message because countbutton is 1. Every time through the loop you will be doing this.

Have you declared lastStatoButton for a reason? you do not appear to be using it and it may be the way to resolve your problem if you detect the change of state rather than the state itself.

Serial.write will only send one byte, so max is 255.

Use serial.print to send the ASCII string of your number.

Please post your code.

Code:

int ledpin = 12;
int counter = 0;

void setup()
{
  //set outpups
  pinMode(ledpin, OUTPUT);
 
  Serial.begin(9600);
}

void loop()
{
 Serial.print(digitalRead(ledpin));
 
 delay(100);
 
  digitalWrite(ledpin, HIGH);
  counter = counter + 1;  // or counter++ does the same thing
  Serial.print(counter);

  delay(1000);
 
  digitalWrite(ledpin, LOW);
 
  delay(1000);
}

Set up a counter and increment it every time you set the LED high. Then print the count just like you are printing the LED status in your sketch.

You need to post all the code because you probably have problems with your variable definitions. For a start you are casting to long and float when you are printing and calculating, which may give you diferent results.

Look at this thread "Simple-yet-powerfull - Serial Command input with numbers" as somewhere to start

http://arduino.cc/forum/index.php/topic,115174.0.html

for the Arduino

That is not the case for other implementations of C/C++. The bigger the precision the more it takes to calculate, especially as there is no floating point hardware support. How many decimal places to you need?

Here's another option. These ribbon cables can be split to suit the number of cores you need. Many sources other than eBay for these.

http://www.ebay.com.au/itm/Rainbow-Color-40-Way-Cable-30cm-Flat-Arduino-Jumper-Cable-Home-Appliance-/180854947595?pt=AU_MobilePhoneAccessories&hash=item2a1bcb7f0b

Yes it all works. The name is irrelevant as the compiler and linker will simply translate it all to a memory address when it does it's job.