msdos/ioports.c

   1 /*
   2  * Emulation of processor ioports.
   3  *
   4  * Copyright 1995 Morten Welinder
   5  */
   6
   7 /* Known problems:
   8    - only a few ports are emulated.
   9    - real-time clock in "cmos" is bogus.  A nifty alarm() setup could
  10      fix that, I guess.
  11 */
  12
  13
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <time.h>
  17 #include "windows.h"
  18 #include "stddebug.h"
  19 /* #define DEBUG_INT */
  20 #include "debug.h"
  21
  22 static BYTE cmosaddress;
  23
  24 static BYTE cmosimage[64] =
  25 {
  26   0x27, 0x34, 0x31, 0x47, 0x16, 0x15, 0x00, 0x01,
  27   0x04, 0x94, 0x26, 0x02, 0x50, 0x80, 0x00, 0x00,
  28   0x40, 0xb1, 0x00, 0x9c, 0x01, 0x80, 0x02, 0x00,
  29   0x1c, 0x00, 0x00, 0xad, 0x02, 0x10, 0x00, 0x00,
  30   0x08, 0x00, 0x00, 0x26, 0x00, 0x00, 0x00, 0x00,
  31   0x00, 0x00, 0x00, 0x00, 0x00, 0x3f, 0x03, 0x58,
  32   0x00, 0x1c, 0x19, 0x81, 0x00, 0x0e, 0x00, 0x80,
  33   0x1b, 0x7b, 0x21, 0x00, 0x00, 0x00, 0x05, 0x5f
  34 };
  35
  36
  37 /**********************************************************************
  38  *          IO_inport
  39  */
  40 DWORD IO_inport( int port, int count )
  41 {
  42     DWORD res = 0;
  43     BYTE b;
  44
  45     dprintf_int(stddeb, "IO: %d bytes from port 0x%02x\n", count, port );
  46
  47     while (count-- > 0)
  48     {
  49         switch (port++)
  50         {
  51         case 0x70:
  52             b = cmosaddress;
  53             break;
  54         case 0x71:
  55             b = cmosimage[cmosaddress & 0x3f];
  56             break;
  57         default:
  58             fprintf( stderr, "Direct I/O read attempted from port %x\n", port);
  59             b = 0xff;
  60             break;
  61         }
  62         res = (res << 8) | b;
  63     }
  64     return res;
  65 }
  66
  67
  68 /**********************************************************************
  69  *          IO_outport
  70  */
  71 void IO_outport( int port, int count, DWORD value )
  72 {
  73     BYTE b;
  74
  75     dprintf_int( stddeb, "IO: 0x%lx (%d bytes) to port 0x%02x\n",
  76                  value, count, port );
  77
  78     while (count-- > 0)
  79     {
  80         b = value & 0xff;
  81         value >>= 8;
  82         switch (port++)
  83         {
  84         case 0x70:
  85             cmosaddress = b & 0x7f;
  86             break;
  87         case 0x71:
  88             cmosimage[cmosaddress & 0x3f] = b;
  89             break;
  90         default:
  91             fprintf( stderr, "Direct I/O write attempted to port %x\n", port );
  92             break;
  93         }
  94     }
  95 }