ethernet_c8051f120.c

c8051f120开发的使用CS8900A以太网控制芯片发送和接收数据包

void UART1_Init (void)
{
   char SFRPAGE_SAVE = SFRPAGE;     // Save Current SFR page
   
   SFRPAGE = UART1_PAGE;
   SCON1   = 0x10;                  // SCON1: mode 0, 8-bit UART, enable RX
   
   SFRPAGE = TIMER01_PAGE;
   TMOD   &= ~0xF0;
   TMOD   |=  0x20;                 // TMOD: timer 1, mode 2, 8-bit reload
   
   
   if (SYSCLK/BAUDRATE/2/256 < 1) {
      TH1 = -(SYSCLK/BAUDRATE/2);
      CKCON |= 0x10;                // T1M = 1; SCA1:0 = xx
   } else if (SYSCLK/BAUDRATE/2/256 < 4) {
      TH1 = -(SYSCLK/BAUDRATE/2/4);
      CKCON &= ~0x13;               // Clear all T1 related bits
      CKCON |=  0x01;               // T1M = 0; SCA1:0 = 01
   } else if (SYSCLK/BAUDRATE/2/256 < 12) {
      TH1 = -(SYSCLK/BAUDRATE/2/12);
      CKCON &= ~0x13;               // T1M = 0; SCA1:0 = 00
   } else {
      TH1 = -(SYSCLK/BAUDRATE/2/48);
      CKCON &= ~0x13;               // Clear all T1 related bits
      CKCON |=  0x02;               // T1M = 0; SCA1:0 = 10
   }   

   TL1 = TH1;                       // initialize Timer1
   TR1 = 1;                         // start Timer1  
   
   SFRPAGE = UART1_PAGE;
   TI1 = 1;                         // Indicate TX1 ready

   SFRPAGE = SFRPAGE_SAVE;          // Restore SFR page

}

//-----------------------------------------------------------------------------
// CS8900A_Reset
//-----------------------------------------------------------------------------
// 
// This procedure resets the CS8900A using its reset pin (P4.5).
//
void CS8900A_Reset(void)
{
   char SFRPAGE_SAVE = SFRPAGE;     // Save Current SFR page
   
   SFRPAGE = TMR3_PAGE;
   TMR3CN = 0x00;                   // Disable Timer3
   TMR3CF &= ~0x18;                 // Count System Clocks/12
   TMR3 = -(SYSCLK / 2500000);      // Load Timer3 with 400ns      
          
   // reset pin (active high) is on P4.5 
   ETH_RESET = 1;                   // Assert the Reset signal
   TR3 = 1;                         // Start Timer3
   while(!TF3);                     // wait for the Timer3 overflow flag.      
   ETH_RESET = 0;                   // Take the CS8900A out of reset
   
   // wait at least 20ms for device to be ready
   TMR3CN = 0x00;                   // Disable Timer3, use system clock/12
   TMR3 = -(SYSCLK / 12 / 50);      // Load Timer3 with 20ms 
   TR3 = 1;                         // Start Timer3
   while(!TF3);                     // wait for the Timer3 overflow flag.      
   
   
   // check to see if the device is ready     
   while( !(PACKETPAGE_Read(IPPREG_SelfST) & INITD) );

   SFRPAGE = SFRPAGE_SAVE;          // Restore SFR page
   
}



//-----------------------------------------------------------------------------
// CS8900A_Init
//-----------------------------------------------------------------------------
//
// This function configures the CS8900A for transmitting and receiving.  It 
// also assigns the CS8900A the MAC address it should respond to.
//
void CS8900A_Init(void)
{ 
   // set which frames will be accepted by the CS8900A
   // the RxOKA bit must be set for the device to operate properly
   PACKETPAGE_Write(IPPREG_RxCTL, RxOKA + PromiscuousA);
   
   // assign the Ethernet MAC address
   PACKETPAGE_Write(IPPREG_IA,      MYMAC.Int[0]);
   PACKETPAGE_Write(IPPREG_IA + 2,  MYMAC.Int[1]);
   PACKETPAGE_Write(IPPREG_IA + 4,  MYMAC.Int[2]);
   
   // enable transmit and receive
   PACKETPAGE_Write(IPPREG_LineCTL,SerTxON | SerRxON);
}

//-----------------------------------------------------------------------------
// Function Definitions
//-----------------------------------------------------------------------------

//-----------------------------------------------------------------------------
// PACKETPAGE_Read
//-----------------------------------------------------------------------------
//
// This function returns the contents of a PacketPage Register
//
// Note: Read high byte first and Write low byte first when communicating with
//       the CS8900A.
//
unsigned int PACKETPAGE_Read (unsigned int IPPREG_address)
{  
   
   UINT register_address;
   UINT retval;
   
   register_address.Int = IPPREG_address;

   // specify register address and set autoincrement off                      
   PACKETPAGE_POINTERL = register_address.Char[1];
   PACKETPAGE_POINTERH = (register_address.Char[0] & 0x7F); 
   
   // read lower 16-bits most significant byte first
   retval.Char[0] = PACKETPAGE_DATA0H;
   retval.Char[1] = PACKETPAGE_DATA0L;

   // return the data register contents
   return retval.Int;
}

//-----------------------------------------------------------------------------
// PACKETPAGE_Write
//-----------------------------------------------------------------------------
//
// This function writes a 16-bit value to a PacketPage Register. 
//
// Note: Read high byte first and write low byte first when communicating with
//       the CS8900A
//
void PACKETPAGE_Write(unsigned int IPPREG_address, unsigned int output_data)
{
   
   UINT register_address;
   UINT dat;
   
   register_address.Int = IPPREG_address;
   dat.Int = output_data;
   
   // specify register address and set autoincrement off                      
   PACKETPAGE_POINTERL = register_address.Char[1];
   PACKETPAGE_POINTERH = (register_address.Char[0] & 0x7F);  
   
   //write the data to the data ports
   PACKETPAGE_DATA0L = dat.Char[1];
   PACKETPAGE_DATA0H = dat.Char[0];
}

//-----------------------------------------------------------------------------
// PACKETPAGE_ReadID
//-----------------------------------------------------------------------------
//
// This function returns the contents of the Product Identification Code 
// register.  This is a 32-bit register at location 0 in the PacketPage memory.
// 
// This register identifies the device as a CS8900A and does not change.
//
unsigned long PACKETPAGE_ReadID ()
{  
   
   ULONG retval;
        
   retval.Int[0] = PACKETPAGE_Read(0x0000);
   retval.Int[1] = PACKETPAGE_Read(0x0002);
   
   return retval.Long;
}
//-----------------------------------------------------------------------------
// CS8900A_RxPoll
//-----------------------------------------------------------------------------
//
// This function polls the CS8900A for the Receive OK event.
//
void CS8900A_RxPoll(void)
{
   unsigned int event;

   event = PACKETPAGE_Read(IPPREG_RxEvent);
   
   if(event & RxOK){
      Receive_Frame();
      return; 
   }
   
   
}

//-----------------------------------------------------------------------------
// RECEIVE_FRAME
//-----------------------------------------------------------------------------
//
//  This function Receives a frame from the CS8900A Data Ports and displays it
//  on a Hyperterminal window.
//
void Receive_Frame(void)
{
   
   UINT status;
   UINT length;
   UINT dat;   
   
   int i;
   
   status.Char[0] = DATA0H;
   status.Char[1] = DATA0L;
    
   length.Char[0] = DATA0H;
   length.Char[1] = DATA0L;
   
   SFRPAGE = UART1_PAGE;

   printf("\n\n New Packet: %d bytes", length.Int);   
   
   printf("\n Destination: ");
   
   for ( i = 0; i < 3; i++) {
      
      dat.Char[0] = DATA0L;
      dat.Char[1] = DATA0H;      
      
      printf("%04X", dat.Int);
      
      length.Int -= 2;
   }

   printf("\n Source:      ");

   for ( i = 0; i < 3; i++) {
      
      dat.Char[0] = DATA0L;
      dat.Char[1] = DATA0H;      
      
      printf("%04X", dat.Int);
      
      length.Int -= 2;
   }   
   
   printf("\n Data: ");
   
   while( ((int) length.Int) > 0 ){
      
      dat.Char[0] = DATA0L;
      dat.Char[1] = DATA0H;      
      
      
      printf("%04X", dat.Int);
      
      length.Int -= 2;



   }
}


//-----------------------------------------------------------------------------
// Send_Frame
//-----------------------------------------------------------------------------
// 
// This function sends an IEEE 802.3 frame to the CS8900A.  Upon entry, there 
// should be valid data in array <buffer>.
//
//                   48-bit  48-bit    16-bit      0-1500 bytes
//  -------------------------------------------------------------------------
// | Preamble | SFD | Dest | Source | Length of  |  Data Field | Pad |  FCS  |
// |          |     | Addr |  Addr  | data field |             |     | (CRC) |
//  -------------------------------------------------------------------------
//   supplied by    |      supplied by the host (TxLength)     | supplied by 
//     CS8900A      |                                          |  CS8900A  

void Send_Frame(char* buffer, int length, MACADDR* dest_address_ptr)
{
   UINT len;
   int status;
   int i;

   // issue a transmit command
   TxCMDL = TRANSMIT_CMDL;
   TxCMDH = TRANSMIT_CMDH;

   // bid for buffer space 
   // data field length + dest field (6) + source field (6) + length field (2)
   len.Int = length + 14;
   TxLENGTHL = len.Char[1];
   TxLENGTHH = len.Char[0]; 

   // error check
   if (PACKETPAGE_Read(IPPREG_BusST) & TxBidErr) while (1);

   // wait for CS8900A Tx ready
   do {
      status = PACKETPAGE_Read(IPPREG_BusST);
   } while (!(status & Rdy4TxNow));

   // write the destination address field
   for (i = 0; i < 6; i+=2 ){
       DATA0L = dest_address_ptr->Char[i];
       DATA0H = dest_address_ptr->Char[i+1];   
   }
   
   // write the source address field
   for (i = 0; i < 6; i+=2 ){
      
       DATA0L = MYMAC.Char[i];
       DATA0H = MYMAC.Char[i+1];   
   }

   // write the data length field
   len.Int = length;
   DATA0L = len.Char[0];
   DATA0H = len.Char[1];

   // write the data field
   // The CS8900A automatically transmits after the last byte is written
   i = 0;
   while (i < length){
      DATA0L = buffer[i];
      i++;
      
      if (i < length){
         DATA0H = buffer[i];
         i++;
      }
   }
 
}