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[on:]

I have tried to wrap my head around this one, but I simple can't figure it out.

Thanks to the TimeNTP example I do know how to get 4 bytes into 1 long, like this:

Code:

byte timebuffer[4];
unsigned long highWord = word(timebuffer[0], timebuffer[1]);
unsigned long lowWord = word(timebuffer[2], timebuffer[3]);
unsigned long epoch = highWord << 16 | lowWord;
setTime(epoch);

but now I want to put the unsigned long epoch into 4 bytes, so I can transmit them.

I tried this, but it is incorrect:

Code:

unsigned long epoch;
byte timebuffer[4];
      timebuffer[0] = (byte) epoch;
      timebuffer[1] = (byte) epoch >> 8;
      timebuffer[2] = (byte) epoch >> 16;
      timebuffer[3] = (byte) epoch >> 24;

[Reply #1 on:]

I tried this, but it is incorrect:

It would help if you would say in what way the results were "incorrect"

Try without the casting:

Code:

unsigned long epoch;
byte timebuffer[4];
      timebuffer[0] = epoch;
      timebuffer[1] = epoch >> 8;
      timebuffer[2] = epoch >> 16;
      timebuffer[3] = epoch >> 24;

And to make it match the original byte order, take the high byte first:

Code:

unsigned long epoch;
byte timebuffer[4];
      timebuffer[0] = epoch >> 24;
      timebuffer[1] = epoch >> 16;
      timebuffer[2] = epoch >> 8;
      timebuffer[3] = epoch;

[Reply #2 on:]

@johnwasser thanks, using your code solved the problem. I did the bit shifting in the wrong order.

Code:

unsigned long epoch;
byte timebuffer[4];
      timebuffer[0] = epoch >> 24;
      timebuffer[1] = epoch >> 16;
      timebuffer[2] = epoch >> 8;
      timebuffer[3] = epoch;