// -------------------------------------------------------------
// R+ connect SDA
// R-SCL
// -------------------------------------------------------------
task main() {
  byte inbuffer[];
  UseRS485(); // (1) Port S4 configured for RS485
  RS485Enable(); // (2) turn on RS485
  RS485Uart(HS_BAUD_115200, HS_MODE_DEFAULT); // (3) initialize UART 112500
  Wait(100);
  TextOut(0, LCD_LINE1, "  NXT <> laptop");
  while (true) {
    while (!RS485DataAvailable()) {}
    RS485Read(inbuffer);    // read data
    ClearScreen();          // clear Screen
    TextOut(0, LCD_LINE1, " NXT <> laptop");
    TextOut(0, LCD_LINE4, ByteArrayToStr(inbuffer));   // dislay data
    int i = strcmp(ByteArrayToStr(inbuffer), "hello");  //compare string was received with "hello" , returns -1, 0, or 1
    // if the string was received are "hello", send back string " World!" to the laptop.
    if(i==0)
    {
    SendRS485String(" World!");
    }
    
    else if(i!=0)
    {
    SendRS485String(" No match" );
    }
    
    Wait(1000);
  }
}