/* ********************************************************************************
 * Arduino_BT_SlaveReply.pde
 * Author     : CH, Chen (Taiwan)
 * Date       : 2012.5.29
 *
 * Data Packetage for Bluetooth Communication:(P22 of NXT Communication Protocol)
 * Length LSB + Length MSB + Command Type + Command + Data bytes...
 *
 * Data Payload of MESSAGEWRITE Direct Command
 * (Received from NXT)
 * Byte 0: Command type(0x00 or 0x80)
 * Byte 1: Direct Command-MESSAGEWRITE(0x09)
 * Byte 2: Inbox number(0 - 9)
 * Byte 3: Message size, include null termination byte
 * Byte 4 - N: Message data, where N = Message size + 3,
               is treated as a string, must include null termination.
 * ******************************************************************************** */
#define REPLY_PACKET_SIZE 66

char replyBuf[REPLY_PACKET_SIZE];
char replyMsg[16]={'H','e','l','l','o',' ','N','X','T',' ','(',' ',' ',' ',')','\0'};
int  sendCountIndex, sendPacketSize;


void build_MESSAGEREAD_returnPackage()
{
  for(int xii=0; xii<REPLY_PACKET_SIZE; xii++) replyBuf[xii] = 0x00;
  replyBuf[0] = 0x40; // Length byte LSB, total packet is 64 bytes
  replyBuf[1] = 0x00; // Length byte MSB
  replyBuf[2] = 0x02; // Byte 0: command type
  replyBuf[3] = 0x13; // Byte 1: command
  replyBuf[4] = 0x00; // Byte 2: Status Byte
  replyBuf[5] = 0x00; // Byte 3: Local Inbox number(0 - 9)
  replyBuf[6] = 0x10; // Byte 4: Message Size, includes the null termination byte
  for(int xii=0; xii<16; xii++) replyBuf[xii+7] = replyMsg[xii]; 
  sendCountIndex = 19;
  sendPacketSize = word(replyBuf[1], replyBuf[0]);
}

void build_MESSAGEWRITE_packet()
{
  for(int xii=0; xii<REPLY_PACKET_SIZE; xii++) replyBuf[xii] = 0x00;
  replyBuf[0] = 0x14; // Length byte LSB, total packet is 20 bytes
  replyBuf[1] = 0x00; // Length byte MSB
  replyBuf[2] = 0x80; // Byte 0: command type
  replyBuf[3] = 0x09; // Byte 1: command
  replyBuf[4] = 0x00; // Byte 2: Inbox number(0 - 9)
  replyBuf[5] = 0x10; // Byte 3: Message Size, includes the null termination byte
  for(int xii=0; xii<16; xii++) replyBuf[xii+6] = replyMsg[xii]; 
  sendCountIndex = 18;  
  sendPacketSize = word(replyBuf[1], replyBuf[0]);
}

void setup()
{
  Serial.begin(9600);
  
  build_MESSAGEWRITE_packet();
  Serial.println("Waiting for Master connecting ...");
  delay(5000);
}

#define WAIT_NEXT_TRANSMIT 3000
void loop()
{
  for(int xii=0; xii<26; xii++)
  {    
     replyBuf[sendCountIndex] = xii+'A';
     for(int xjj=0; xjj<(sendPacketSize+2); xjj++)
     {
        Serial.write(replyBuf[xjj]);
        delay(1);
     }
     delay(WAIT_NEXT_TRANSMIT);
  }
}