Serial.Write(buf,Len) how to read Serial sended array of byte

Question

hello i'm trying to send array of byte with Serial.Write(buf,Len) but don't know hot to read this code with receiver.

SENDER code:

byte buf[4]={1,2,3,4};
void setup(){
Serial.begin(250000);
}

void loop(){
Serial.write(buf,4);
}

RECEIVER code (WRONG)

byte buf[4];

void setup() {
  Serial.begin(250000); // how suggest 

}

void loop() {
  int i = 0;

  if (Serial.available()) {
    Serial.readBytes(buf,4);
    Serial.print(buf[0]);
    Serial.print(buf[1]);
    Serial.print(buf[2]);
    Serial.print(buf[3]);
  }
}

How to receive this ??

Answer 1

You have two issues:

Firstly the transmitter is set to 250000 baud (a non-standard rate) while the receiver is set to 9600 baud. Both need to be set to the same rate.

Secondly the transmitter is constantly sending data and the receiver is constantly reading it, there is no way to ensure the two are synchronized. So your receive buffer could well end up being the end of one set of data and then the start of the next e.g. 3,4,1,2. If all you are sending is the same loop over and over this doesn't matter but for real world data it's an issue. If you have a value which you know will never be in your data (e.g. 0 or 0xff) then you can use that as a start of data marker, if not then things get a little more tricky.