source/src/vm/fmr50/floppy.cpp

   1 /*
   2         FUJITSU FMR-50 Emulator 'eFMR-50'
   3         FUJITSU FMR-60 Emulator 'eFMR-60'
   4
   5         Author : Takeda.Toshiya
   6         Date   : 2008.04.30 -
   7
   8         [ floppy ]
   9 */
  10
  11 #include "floppy.h"
  12 #include "../i8259.h"
  13 #include "../mb8877.h"
  14
  15 void FLOPPY::initialize()
  16 {
  17         drvreg = drvsel = 0;
  18         irq = irqmsk = false;
  19         changed[0] = changed[1] = changed[2] = changed[3] = false;
  20 }
  21
  22 void FLOPPY::write_io8(uint32 addr, uint32 data)
  23 {
  24         int nextdrv = drvsel;
  25
  26         switch(addr & 0xffff) {
  27         case 0x208:
  28                 // drive control register
  29                 irqmsk = ((data & 1) != 0);
  30                 update_intr();
  31                 d_fdc->write_signal(SIG_MB8877_MOTOR, data, 0x10);
  32                 d_fdc->write_signal(SIG_MB8877_SIDEREG, data, 4);
  33                 break;
  34         case 0x20c:
  35                 // drive select register
  36                 if(data & 1) {
  37                         nextdrv = 0;
  38                 } else if(data & 2) {
  39                         nextdrv = 1;
  40                 } else if(data & 4) {
  41                         nextdrv = 2;
  42                 } else if(data & 8) {
  43                         nextdrv = 3;
  44                 }
  45                 if(drvsel != nextdrv) {
  46                         d_fdc->write_signal(SIG_MB8877_DRIVEREG, drvsel = nextdrv, 3);
  47                 }
  48                 drvreg = data;
  49                 break;
  50         }
  51 }
  52
  53 uint32 FLOPPY::read_io8(uint32 addr)
  54 {
  55         switch(addr & 0xffff) {
  56         case 0x208:
  57                 if(changed[drvsel]) {
  58                         changed[drvsel] = false;
  59                         return d_fdc->fdc_status() | 0xe1;      // fdd*2
  60                 }
  61 //              return d_fdc->fdc_status() | 0x60;      // fdd*1
  62                 return d_fdc->fdc_status() | 0xe0;      // fdd*2
  63         case 0x20c:
  64                 return drvreg;
  65         }
  66         return 0xff;
  67 }
  68
  69 void FLOPPY::write_signal(int id, uint32 data, uint32 mask)
  70 {
  71         if(id == SIG_FLOPPY_IRQ) {
  72                 irq = ((data & mask) != 0);
  73                 update_intr();
  74         }
  75 }
  76
  77 void FLOPPY::update_intr()
  78 {
  79         d_pic->write_signal(SIG_I8259_CHIP0 | SIG_I8259_IR6, irq && irqmsk ? 1 : 0, 1);
  80 }
  81