Read byte array from file

Processing Coding Questions
1 
void Impuls(File selection) {
  if (selection == null) {
    println("Window was closed or the user hit cancel.");
  } else {
    println("User selected " + selection.getAbsolutePath());
    String[] lines = loadStrings(selection.getAbsolutePath());
    inputPULI.setValue(lines.length); // ПРОЧИТАЛИ СТРОКИ
    
        String[] items = lines[0].split(" ");
        String[] items1 = lines[1].split(" ");
        String[] items2 = lines[2].split(" ");
        String[] items3 = lines[3].split(" ");
        String[] items4 = lines[4].split(" ");
            println(items[0]);
            serialPort.write(items[0]);
            println(items[1]);
            serialPort.write(items[1]);
            println(items1[0]);
            serialPort.write(items1[0]);
            println(items1[1]);
            serialPort.write(items1[1]);
            println(items2[0]);
            serialPort.write(items2[0]);
            println(items2[1]);
            serialPort.write(items2[1]);
            println(items3[0]);
            serialPort.write(items3[0]);
            println(items3[1]);
            serialPort.write(items3[1]);
            println(items4[0]);
            serialPort.write(items4[0]);
            println(items4[1]);
            serialPort.write(items4[1]);
           {
           writeuploadimpuls();
           }      
          }
}

Run File dodo.pde
See the screen “123.png” The screenshot shows an arrow where to open the file!

123
1231600×900 202 KB

When reading the file “Impuls.txt” through the download button, the lines are read (number of pulses of bullets)
Through a space in the console, for your own understanding, the first 5 pulses with numbering are displayed in a column.
Then these impulses 5 pieces (so far) are written to the port in the form of characters in the “hex” display mode.
Code section GUI tab - lines 356-396.
Line 393 The button handler is associated with the Protokol tab lines 41-54.
Now the characters of the string are sent to the port, they will be hidden:
1
8500
2
8470
3
8450
4
8440
5
8435
How to send numbers without numbering 85008470845084408435???
8500 is 4 bytes
But the whole task is reduced to one, you need to work with bytes, not strings, that is:

  1. Read byte array from file (reading bytes from a file) and send it, then to the W25Q memory.
  2. There is loadstrings, it gives a string array, but there is a type of such readbytes, I don’t know the name, it gives a byte array. It is necessary to look in the processing documentation.

Full project in the archive:
https://drive.google.com/file/d/1KzsV4J_czBPj80Jm0PQnzeRVq3h7BObB/view?usp=drivesdk