cs8900.c

此源代码

/******************************************************************
 *****                                                        *****
 *****  Name: cs8900.c                                        *****
 *****  Ver.: 1.0                                             *****
 *****  Date: 07/05/2001                                      *****
 *****  Auth: Andreas Dannenberg                              *****
 *****        HTWK Leipzig                                    *****
 *****        university of applied sciences                  *****
 *****        Germany                                         *****
 *****  Func: ethernet packet-driver for use with LAN-        *****
 *****        controller CS8900 from Crystal/Cirrus Logic     *****
 *****                                                        *****
 ******************************************************************/

#include "cs8900.h"
// Keil: Following lines are needed to access the CS8900 on the MCB167NET board
#include <absacc.h> 
#include <tcpip.h> 
#define CS8900IOBASE 0x100300
// Keil: End of added lines

// configure port-pins for use with LAN-controller,
// reset it and send the configuration-sequence
// (InitSeq[])

void Init8900(void)
{
  unsigned int i;

// Keil: function modified to access the CS8900 on the address/data bus
  Write8900(ADD_PORT, PP_SelfCTL);
  Write8900(DATA_PORT, POWER_ON_RESET);            // Reset the Ethernet-Controller

  Write8900(ADD_PORT, PP_SelfST);
  while (!(Read8900(DATA_PORT) & INIT_DONE));      // wait until chip-reset is done
  
  for (i = 0; i < sizeof InitSeq / sizeof (TInitSeq); i++) // configure the CS8900
  {
    Write8900(ADD_PORT, InitSeq[i].Addr);
    Write8900(DATA_PORT, InitSeq[i].Data);
  }
}

// writes a word in little-endian byte order to
// a specified port-address

void Write8900(unsigned char Address, unsigned int Data)
{
// Keil: function modified to access the CS8900 on the address/data bus
  HVAR(unsigned int,Address + CS8900IOBASE) = Data;
}

// writes a word in little-endian byte order to TX_FRAME_PORT

void WriteFrame8900(unsigned int Data)
{
// Keil: function modified to access the CS8900 on the address/data bus
  HVAR(unsigned int,TX_FRAME_PORT + CS8900IOBASE) = Data;
}

// copies bytes from MCU-memory to frame port
// NOTES: * an odd number of byte may only be transfered
//          if the frame is written to the end!
//        * MCU-memory MUST start at word-boundary

void CopyToFrame8900(void *Source, unsigned int Size)
{
  unsigned int * piSource;                       // Keil: Pointer added to correct expression
  
  piSource = Source;                             // Keil: Line added
  while (Size > 1) {
//  WriteFrame8900(*((unsigned int *)Source)++); // Keil: Line replaced with following line
    WriteFrame8900(*piSource++);
    Size -= 2;
  }
  
  if (Size)                                      // if odd num. of bytes...
//  WriteFrame8900(*(unsigned char *)Source);    // Keil: Line replaced with following line
    WriteFrame8900(*(unsigned char *)piSource);  // write leftover byte (the LAN-controller
}                                                // ignores the highbyte)

// reads a word in little-endian byte order from
// a specified port-address

unsigned int Read8900(unsigned char Address)
{
  unsigned int ReturnValue;

// Keil: function modified to access the CS8900 on the address/data bus
  ReturnValue = HVAR(unsigned int,Address + CS8900IOBASE);
  
  return ReturnValue;
}

// reads a word in little-endian byte order from RX_FRAME_PORT

unsigned int ReadFrame8900(void)
{
  unsigned int ReturnValue;

// Keil: function modified to access the CS8900 on the address/data bus
  ReturnValue = HVAR(unsigned int,RX_FRAME_PORT + CS8900IOBASE);
  
  return ReturnValue;
}

// reads a word in big-endian byte order from RX_FRAME_PORT
// (useful to avoid permanent byte-swapping while reading
// TCP/IP-data)

unsigned int ReadFrameBE8900(void)
{
  unsigned int ReturnValue;

// Keil: function modified to access the CS8900 on the address/data bus
  ReturnValue = HVAR(unsigned int,RX_FRAME_PORT + CS8900IOBASE);
  ReturnValue = SwapBytes(ReturnValue);
  
  return ReturnValue;
}

// reads a word in little-endian byte order from
// a specified port-address
// NOTE: this func. xfers the high-byte 1st, must be used to
//       access some special registers (e.g. RxStatus)

unsigned int ReadHB1ST8900(unsigned char Address)
{
  unsigned int ReturnValue;

// Keil: function modified to access the CS8900 on the address/data bus
  ReturnValue = HVAR(unsigned int,Address + CS8900IOBASE);
  
  return ReturnValue;
}

// copies bytes from frame port to MCU-memory
// NOTES: * an odd number of byte may only be transfered
//          if the frame is read to the end!
//        * MCU-memory MUST start at word-boundary

void CopyFromFrame8900(void *Dest, unsigned int Size)
{
  unsigned int * piDest;                         // Keil: Pointer added to correct expression

  piDest = Dest;                                 // Keil: Line added
  while (Size > 1) {
//  *((unsigned int *)Dest)++ = ReadFrame8900(); // Keil: Line replaced with following line
    *piDest++ = ReadFrame8900();
    Size -= 2;
  }
  
  if (Size)                                      // check for leftover byte...
//  *(unsigned char *)Dest = ReadFrame8900();    // Keil: Line replaced with following line
    *(unsigned char *)piDest = ReadFrame8900();  // the LAN-Controller will return 0
}                                                // for the highbyte

// does a dummy read on frame-I/O-port
// NOTE: only an even number of bytes is read!

void DummyReadFrame8900(unsigned int Size)       // discards an EVEN number of bytes
{                                                // from RX-fifo
  while (Size > 1) {
    ReadFrame8900();
    Size -= 2;
  }
}

// requests space in CS8900's on-chip memory for
// storing an outgoing frame

void RequestSend(unsigned int FrameSize)
{
  Write8900(TX_CMD_PORT, TX_START_ALL_BYTES);
  Write8900(TX_LEN_PORT, FrameSize);
}

// check if CS8900 is ready to accept the
// frame we want to send

unsigned int Rdy4Tx(void)
{
  Write8900(ADD_PORT, PP_BusST);
  return (Read8900(DATA_PORT) & READY_FOR_TX_NOW);
}