/* USB Host to PL2303-based USB GPS unit interface */
/* Navibee GM720 receiver - Sirf Star III */
/* USB support */
#include <usbhub.h>
/* CDC support */
#include <cdcacm.h>
#include <cdcprolific.h>

class PLAsyncOper : public CDCAsyncOper
{
public:
    virtual uint8_t OnInit(ACM *pacm);
};

uint8_t PLAsyncOper::OnInit(ACM *pacm)
{
    uint8_t rcode;
    
    // Set DTR = 1
    rcode = pacm->SetControlLineState(1);

    if (rcode)
    {
        ErrorMessage<uint8_t>(PSTR("SetControlLineState"), rcode);
        return rcode;
    }

    LINE_CODING lc;
    lc.dwDTERate  = 4800;   //default serial speed of GPS unit  
    lc.bCharFormat  = 0;
    lc.bParityType  = 0;
    lc.bDataBits  = 8;  
  
    rcode = pacm->SetLineCoding(&lc);

    if (rcode)
        ErrorMessage<uint8_t>(PSTR("SetLineCoding"), rcode);
            
    return rcode;
}

USB     Usb;
USBHub     Hub(&Usb);
PLAsyncOper  AsyncOper;
PL2303       Pl(&Usb, &AsyncOper);
uint32_t read_delay;
#define READ_DELAY 100

void setup()
{
  Serial.begin( 115200 );
  while (!Serial); // Wait for serial port to connect - used on Leonardo, Teensy and other boards with built-in USB CDC serial connection
  Serial.println("Start");

  if (Usb.Init() == -1)
      Serial.println("OSCOKIRQ failed to assert");
      
  delay( 200 ); 
}

void loop()
{
uint8_t rcode;
uint8_t  buf[64];    //serial buffer equals Max.packet size of bulk-IN endpoint           
uint16_t rcvd = 64;   

  Usb.Task();
    
    if( Pl.isReady()) {  
       /* reading the GPS */
       if( read_delay < millis() ){
       read_delay += READ_DELAY;  
       rcode = Pl.RcvData(&rcvd, buf);
        if ( rcode && rcode != hrNAK )
           ErrorMessage<uint8_t>(PSTR("Ret"), rcode);            
            if( rcvd ) { //more than zero bytes received
              for( uint16_t i=0; i < rcvd; i++ ) {
                  Serial.print((char)buf[i]); //printing on the screen
              }//for( uint16_t i=0; i < rcvd; i++...              
            }//if( rcvd
       }//if( read_delay > millis()...            
    }//if( Usb.getUsbTaskState() == USB_STATE_RUNNING..    
}