// digi6e.c

#include "digi6e.h"

// configure the array number location to a port
// and bit number dictated by portselect
int ConfigureOutput(int arraynumber, int portselect)
{
  int x;

  if(arraynumber < 0 || arraynumber > 23)
    return 0; // illegal number

  if(portselect < 0 || portselect > 23)
    return 0; // illegal number

  if(OutputControl[arraynumber] == NULL)
  {
    if((OutputControl[arraynumber] = malloc(sizeof(struct OC))) == NULL)
    {
      printf("Not enough memory\n");
      return 0;
    }
  }

  x = portselect >> 3; // the port number is in bits 3 and 4

  switch(x) // 0 = Port A, 1 = Port B, 2 = Port C
  {
    case 0:
    OutputControl[arraynumber]->PortAddress = ppi_porta; // address for Port A
    OutputControl[arraynumber]->PortData = &porta_val;   // point to Port A data value
    break;

    case 1:
    OutputControl[arraynumber]->PortAddress = ppi_portb; // address for Port B
    OutputControl[arraynumber]->PortData = &portb_val;   // point to Port B data value
    break;

    case 2:
    OutputControl[arraynumber]->PortAddress = ppi_portc; // address for Port C
    OutputControl[arraynumber]->PortData = &portc_val;   // point to Port C data value
    break;
  }

  OutputControl[arraynumber]->OnMask = 1 << (portselect & 7); // shift by bits[2:0]
  OutputControl[arraynumber]->OffMask = ~OutputControl[arraynumber]->OnMask;

// /* remove the double slash rem to skip debug print statements

  printf("arraynum=%02d port select=%02d ",arraynumber,portselect);

  printf("Addr=%#X "
  ,OutputControl[arraynumber]->PortAddress);

  printf("*Data=%X "
  ,*OutputControl[arraynumber]->PortData);

  printf("OnMask=");
  for(x=128; x>0; x/=2)
  {
    if(x & OutputControl[arraynumber]->OnMask)
      printf("1");
    else printf("0");
  }

  printf(" OffMask=");
  for(x=128; x>0; x/=2)
  {
    if(x & OutputControl[arraynumber]->OffMask)
      printf("1");
    else printf("0");
  }
  printf("\n");

// remove the double slash rem to skip debug print statements */ 

  return 1;
}

// portflag settings:
// A CU B CL
// x  x x  x
// low = output, hi = input
// example:
// 0101
// A = out, CU = in, B = out, CL = in

int portflag = 0x0f;  // set by set_up_ppi() -- init to all inputs


// set the last array location so isr won't waste time looking
int SetLast(int arraynumber)
{
  if(arraynumber < 0 || arraynumber > 23)
    return 0;

  if(OutputControl[arraynumber] == NULL)
  {
    if((OutputControl[arraynumber] = malloc(sizeof(struct OC))) == NULL)
    {
      printf("Not enough memory for output control.\n");
      return 0;
    }
  }

  // zero out members
  memset(OutputControl[arraynumber], 0, sizeof(struct OC));

  OutputControl[arraynumber]->type = 255; // show as last
}

// free and  null out error location
int ClearPort(int arraynumber)
{
  if(OutputControl[arraynumber] != NULL)
  {
    free(OutputControl[arraynumber]);
    OutputControl[arraynumber] = NULL;
  }
  return 0; // always 0 -- illegal number
}


// free the output control structures
void FreeOutputControl(void)
{
  int x;

  for(x=0; x<24; x++)
  {
    if(OutputControl[x] != NULL)
      free(OutputControl[x]);
  }
}

// set up the ppi according to the dictates of the mode argument
void set_up_ppi(int mode)
{
  unsigned control = base + 0x23;
  int command;

  // make certain control locations start at NULL
  for(command=0; command<24; command++)
    OutputControl[command] = NULL;

  mode>>=6; // shift the mode value to the right 6 places

  command = (mode & 0x0c) << 1; // shift bits 2 and 3 into positions 4 and 5
  command += (mode & 3); // add in bits 0 and 2
  command |= 0x80; // OR in bit 7 for PPI set up

  outp(control, command); // set according to mode command

} // end set_up_ppi()



// ================================================================
//                         is_closure
// 1. Return -1 error indicator if the input
//    is less than 1 or greater than 67.
//
// 2. If there is a fall-through from the above and the input
//    is less than 4, return the status based on switch_port.
//
// 3. If there is a fall-through from both of the above, then
//    return the status based on the matrix:

//             |-----------------------|
// Port A bit 0| 4| 5| 6| 7| 8| 9|10|11|
// Port A bit 1|12|13|14|15|16|17|18|19|
// Port A bit 2|20|21|22|23|24|25|26|27|
// Port A bit 3|28|29|30|31|32|33|34|35|
// Port A bit 4|36|37|38|39|40|41|42|43|
// Port A bit 5|44|45|46|47|48|49|50|51|
// Port A bit 6|52|53|54|55|56|57|58|59|
// Port A bit 7|60|61|62|63|64|65|66|67|
//             |-----------------------|
//  Port B bits  0  1  2  3  4  5  6  7

// ================================================================
int is_closure(int input)
{

  if(input < 1 || input > 67) // if the input is less than 1 or greater
    return -1;                // than 67, then return -1 showing an error

  // we fell through the above so see if input is less than 4
  if(input < 4)
    return ((inp(switch_port) >> (input + 3)) & 1) ^ 1; // yes, return using switch_port

  // input is >= 4 so look at the matrix
  // by first setting up Port A to take the appropriate row bit low
  porta_val = (~(1 << ( (input - 4) / 8) )) & 0xff;

  // clear the appropriate Port A bit 
  outp(ppi_porta, porta_val);

  // determine what column bit to look at for this input
  portb_mask = (1 << ((input - 4) % 8)) & 0xff;

  // a closure will cause a low, so invert the return 
  if(!(inp(ppi_portb) & portb_mask))
    return 1;

  return 0;

}// end is_closure()

// get the port -- this will grow into an auto-detect function in the future 
unsigned oldget_port(void)
{
  base = 0x200; // all switches on -- change if desired
  switch_port = base + 0x18;
  ppi_porta = base + 0x20;
  ppi_portb = base + 0x21;
  ppi_portc = base + 0x22;
  return base;
  
} // end get_port()

// find hardware port if one exists
unsigned get_port(void)
{
  int x;
  static unsigned local_port;
  unsigned int not_ready_count,ready_count;

  if(local_port == 32767)
    return 0;

  if(local_port > 0)
    return local_port;

  for(x=0x200; x<0x3c0; x+=0x40)
  {
    not_ready_count = 32767;
    ready_count = 32767;

    outp(x,0); /* start conversion */

    while((inp(x+0x18) & 0x80) && --not_ready_count); /* wait for not ready */

    while(!(inp(x+0x18) & 0x80) && --ready_count); /* wait for ready */

//printf("ready_count = %d\n",ready_count);

    if(ready_count < 32767 && ready_count > 0)
    {
      local_port = base = x;
      switch_port = base + 0x18;
      ppi_porta = base + 0x20;
      ppi_portb = base + 0x21;
      ppi_portc = base + 0x22;
      return base;
    }
  }

  local_port = 32767;
  return 0;
}


void blinker(long on, long off)
{
  int x;
  long y,z;

  for(x=0x80; x>0; x>>=1)
  {
    outp(ppi_porta, x);
    for(y=0L; y<on; y++);

    outp(ppi_porta, 0);
    for(z=0L; z<off; z++);
  }

  for(x=2; x<0x80; x<<=1)
  {
    outp(ppi_porta, x);
    for(y=0L; y<on; y++);

    outp(ppi_porta, 0);
    for(z=0L; z<off; z++);
  }

}

void blinker2(long on)
{
  int x;
  long z;

  porta_val = 0;

  for(x=0x80; x>0; x>>=1)
  {
    porta_val |= x;
    outp(ppi_porta, porta_val);
    printf("%3X",porta_val);
    for(z=0L; z<on; z++);
  }

  for(x=1; x<=0x80; x<<=1)
  {
    porta_val ^= x;
    outp(ppi_porta, porta_val);
    printf("%3X",porta_val);
    for(z=0L; z<on; z++);
  }
  puts("");
}

void btoa(void)
{
    outp(ppi_porta, ~inp(ppi_portb));
}

void motor(long on, long off)
{
  int x;
  long y,z;

  printf("ON  ");
  outp(ppi_porta, 0xff);
  for(y=0L; y<on; y++);

  printf("OFF ");
  outp(ppi_porta, 0);
  for(z=0L; z<off; z++);
}

void portaon(void)
{
  outp(ppi_porta, 0xff);
}

void portaoff(void)
{
  outp(ppi_porta, 0);
}

void portboff(void)
{
  outp(ppi_portb, 0);
}

void portcoff(void)
{
  outp(ppi_portc, 0);
}

// turn on an output node
// ======================== old config routine ============================

// configure the array number location to a port
// and bit number dictated by portselect
int oldConfigureOutput(int arraynumber, int portselect)
{
  int x;

  if(arraynumber < 0 || arraynumber > 23)
  {
    printf("arraynumber error --- %d\n",arraynumber);
    return 0; // illegal number
  }

  if(portselect < 0 || portselect > 23)
  {
    printf("portselect error --- %d\n",portselect);
    return 0; // illegal number
  }

  if(OutputControl[arraynumber] == NULL)
  {
    if((OutputControl[arraynumber] = malloc(sizeof(struct OC))) == NULL)
    {
      printf("Not enough memory\n");
      return 0;
    }
  }

  // zero out members
  memset(OutputControl[arraynumber], 0, sizeof(struct OC));

  x = portselect >> 3; // the port number is in bits 3 and 4

  switch(x) // 0 = Port A, 1 = Port B, 2 = Port C
  {
    case 0:
    OutputControl[arraynumber]->PortAddress = ppi_porta; // address for Port A
    OutputControl[arraynumber]->PortData = &porta_val;   // point to Port A data value
    break;

    case 1:
    OutputControl[arraynumber]->PortAddress = ppi_portb; // address for Port B
    OutputControl[arraynumber]->PortData = &portb_val;   // point to Port B data value
    break;

    case 2:
    OutputControl[arraynumber]->PortAddress = ppi_portc; // address for Port C
    OutputControl[arraynumber]->PortData = &portc_val;   // point to Port C data value
    break;
  }

  // shift by bits[2:0]
  OutputControl[arraynumber]->OnMask = 1 << (portselect & 7);
  OutputControl[arraynumber]->OffMask = ~OutputControl[arraynumber]->OnMask;

 /* add double slash rem to print debug statements

  printf("arraynum=%02d port select=%02d ",arraynumber,portselect);

  printf("Addr=%#X "
  ,OutputControl[arraynumber]->PortAddress);

  printf("*Data=%X "
  ,*OutputControl[arraynumber]->PortData);

  printf("OnMask=");
  for(x=128; x>0; x/=2)
  {
    if(x & OutputControl[arraynumber]->OnMask)
      printf("1");
    else printf("0");
  }

  printf(" OffMask=");
  for(x=128; x>0; x/=2)
  {
    if(x & OutputControl[arraynumber]->OffMask)
      printf("1");
    else printf("0");
  }
  printf("\n");

 add double slash rem to print debug statements */ 

  return 1;
}

// end digital.c