Code simplification

Projects Programming
1

This should be self explanatory. I want this function to convert 4 bytes into a single long.

Say I call the function as:

void send_data(250, 10, 134, 156, 98);

Noiw the actual function:

void send_data(byte address, byte byte1, byte byte2, byte byte3, byte byte4)
{
  byte mybyte[4] = 0;
  
  mybyte[0] = byte1;
  mybyte[1] = byte2;
  mybyte[2] = byte3;
  mybyte[3] = byte4;
  
  // Encode the variables into a 32 bit variable
  for ( int i = 0; i < 4; ++i )
  {
    (reinterpret_cast<char*>(&transmitterdata))[i] = mybyte[i];
  }

  ... now, do whatever with the processed variable...
  
}

I'm sure this can be simplified. Would it be possible to call the function as:

void send_data(address, myarray[4]);

Thanks

2

Should the number end up as: 2,501,013,415,698? Your example has 5 bytes, not 4.

3

Maybe use a union.

union LONGBYTES
{
  byte bytes[4];
  long longvalue;
};


LONGBYTES data;


void setup() {

data.bytes[0]=3;
data.bytes[1]=2;
data.bytes[2]=1;
data.bytes[3]=0;

Serial.begin(9600);
Serial.println(data.longvalue);
}

Not tested.

4

The code already converts the 4 bytes to a long, but I would like to pass an array to the function rather than 4 individual bytes. Is this possible?

5

casemod:
The code already converts the 4 bytes to a long, but I would like to pass an array to the function rather than 4 individual bytes. Is this possible?

hint: the name of the array is a pointer to the first element of the array

6

something like this:

byte myByte[4] = {10, 134, 156, 98};
  

void setup() 
{
  Serial.begin(9600);
  send_data(250, myByte);  // myByte degrades to a pointer to myByte[0]
}

void loop() 
{

}

void send_data(byte address, byte* value)
{ 
  // Encode the variables into a 32 bit variable
  for ( int i = 0; i < 4; i++ )
  {
    Serial.println(value[i]);
    //(reinterpret_cast<char*>(&transmitterdata))[i] = value[i];
  }
}