/* ------------------------------------------------------- --------------
   Low Level Dallas MicroLan interface software
   
   Copyright 1997 by Brian C. Lane
   All rights Reserved
   
   -----------------------------------------------------------------------*/
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>

struct _roms {
	char		*roms;			/* Array of 8 bytes	*/
	int		max;			/* Maximum number	*/
};

/* ----------------------------------------------------------------------- *
   Setup - Setup the tty for 115.2k operation

   returns 0 if successful and -1 if it failed
 * ----------------------------------------------------------------------- */
int Setup( unsigned char CmPt )
{
  unsigned int far *ptr = (unsigned int far *) 0x00400000;
  unsigned int SPA;

  /* Check to see if it is a valid com port number and address */
  SPA = *(ptr+CmPt-1);		/* Get the address */
  if( CmPt < 1 || CmPt > 4 || !SPA )
    return -1;

  outportb( SPA+3, 0x83 );		/* Set DLAB */
  outportb( SPA  , 0x01 );		/* Bit rate is 115200 */
  outportb( SPA+1, 0x00 );
  outportb( SPA+3, 0x03 );		/* 8 data, 1 stop, no parity */
  outportb( SPA+1, 0x00 );		/* No Interrupts */
  outportb( SPA+4, 0x03 );		/* RTS and DTR on */

  return CmPt;
}


/* ----------------------------------------------------------------------- *
   Reset the One Wire device and look for a presence pulse from it

   returns:	0 - No Presence/device detected
		1 - Presence Detected no alarm
		2 - Alarm followed by pressence
		-3 - Short to Ground
		-4 - Serial device error

   This expects the device to already be opened and pass the fd of it

 * ----------------------------------------------------------------------- */
int TouchReset( unsigned char comport, int timeout )
{
  unsigned int SPA, F, X, Y, tmp, trst = 0;
  unsigned int far *ptr = (unsigned int far *) 0x00400000;
  unsigned long far *sysclk = (unsigned long far *) 0x0040006C;
  unsigned long M;

  /* Get the port address */
  SPA = *(ptr+comport-1);

  if( !SPA )
    return -4;

  outportb( SPA+3, 0x83 );		/* Set DLAB */
  outportb( SPA  , 0x01 );		/* Bit rate is 115200 */
  outportb( SPA+1, 0x00 );
  outportb( SPA+3, 0x03 );		/* 8 data, 1 stop, no parity */
  outportb( SPA+1, 0x00 );		/* No Interrupts */
  outportb( SPA+4, 0x03 );		/* RTS and DTR on */

  /* Clear the buffers */
  M = *sysclk + 1000;
  do
  {
    tmp = inportb(SPA+5) & 0x60;
  } while ( (tmp != 0x60 ) && (*sysclk <= M) );

  /* Flush input */
  M = *sysclk + 1000;
  while( ( inportb(SPA+5) & 0x01)  && (*sysclk <= M) )
  {
    X = inportb(SPA);
  }

  outportb( SPA+3, 0x83 );		/* Set DLAB */
  outportb( SPA+1, 0x00 );		/* Bit rate is 0x0B = 10473 */
  outportb( SPA  , 0x0B );		/* 0x0C = 9600 baud */
  outportb( SPA+3, 0x03 );  		/* 8 data, 1 stop, no parity */

  outportb( SPA  , 0xF0 );		/* Send the reset pulse */

  M = *sysclk + 50;

  /* Wait until character back or timeout */
  do
  {
    Y = inportb(SPA+5);			/* Read status register		*/
    F = Y & 0x01;
  } while( !F && (*sysclk <= M) );

  if( F )
    X = inportb( SPA );
  else
    return -3;

  outportb( SPA+3, 0x83 );		/* Set DLAB */
  outportb( SPA  , 0x01 );		/* Bit rate is 115200 */
  outportb( SPA+3, 0x03 );		/* 8 data, 1 stop, no parity */
  return 1;

  #ifdef MORE_CHECKS
  if( X != 0xF0 )			/* If more bits back than sent */
  {

    trst = 1;
    if( ( Y & 0x18 ) != 0 )
    {
      trst = 2;

      /* Clear the buffers */
      M = *sysclk + 1000;
      do
      {
	tmp = inportb(SPA+5) & 0x60;
      } while ( (tmp != 0x60 ) && (*sysclk <= M) );

      M = *sysclk + 50;
      /* wait until character back or timeout */
      do
      {
	Y = inportb( SPA+5 );
	F = Y & 0x01;
      } while( !F && (*sysclk <= M) );

      if( F )
	X = inportb( SPA );
      else
	return 3;
    }
  }

  outportb( SPA+3, 0x83 );		/* Set DLAB */
  outportb( SPA  , 0x01 );		/* Bit rate is 115200 */
  outportb( SPA+3, 0x03 );		/* 8 data, 1 stop, no parity */

  return trst;
  #endif
}


/* ----------------------------------------------------------------------- *
   TouchBits - Read/Write a number of bits to the TouchMemory device

   Expects that the tty is set up for 115.2k operation

   returns the read byte if one received
 * ----------------------------------------------------------------------- */
int TouchBits( int comport, int timeout, int nbits, unsigned char outch)
{
  unsigned char inch=0, sendbit, Mask=1;
  unsigned int SPA, tmp;
  unsigned far *ptr = (unsigned int far *) 0x00400000;
  unsigned long far *sysclk = (unsigned long far *) 0x0040006C;
  unsigned long M;
  int		x;

  /* Get the serial port address */
  SPA = *(ptr+comport-1);

  /* Clear the buffers */
  M = *sysclk + 1000;
  do
  {
    tmp = inportb(SPA+5) & 0x60;
  } while ( (tmp != 0x60 ) && (*sysclk <= M) );

  /* Flush input */
  M = *sysclk + 1000;
  while( ( inportb(SPA+5) & 0x01)  && (*sysclk <= M) )
  {
    inportb(SPA);
  }

  /* get first bit ready to go out */
  sendbit = (outch & 0x01) ? 0xFF : 0x00;

  /* loop to send and receive 8 bits */
  for( x = 0; x < nbits; x++ )
  {
    outportb( SPA, sendbit);

    /* Get next bit ready */
    Mask <<= 1;
    sendbit = (outch & Mask) ? 0xFF : 0x00;

    /* shift input char over ready for next bit */
    inch >>= 1;

    M = *sysclk + 50;

    for(;;)
    {
      /* return if out of time */
      if( *sysclk > M )
	return 0xFF;

      if( inportb(SPA+5) & 0x01 )
      {
	inch |= ((inportb(SPA) & 0x01 ) ? 0x80 : 0x00);
	break;
      }
    }
  }

  return inch;
}

/* ----------------------------------------------------------------------- *
   TouchByte - Read/Write a byte to the TouchMemory device

   Expects that the tty is set up for 115.2k operation

   returns the read byte if one received
 * ----------------------------------------------------------------------- */
int TouchByte( int comport, int timeout, unsigned char outch  )
{
  return TouchBits( comport, timeout, 8, outch );
}