source/src/vm/mz2800/joystick.cpp

   1 /*
   2         SHARP MZ-2800 Emulator 'EmuZ-2800'
   3
   4         Author : Takeda.Toshiya
   5         Date   : 2007.08.14 -
   6
   7         [ joystick ]
   8 */
   9
  10 #include "joystick.h"
  11
  12 void JOYSTICK::initialize()
  13 {
  14         mode = 0xf;
  15         joy_stat = emu->get_joy_buffer();
  16 }
  17
  18 void JOYSTICK::write_io8(uint32_t addr, uint32_t data)
  19 {
  20         mode = data;
  21 }
  22
  23 uint32_t JOYSTICK::read_io8(uint32_t addr)
  24 {
  25         uint32_t val = 0x3f;
  26         int num = (mode & 0x40) ? 1 : 0;
  27         bool dir = true;
  28
  29         // trigger mask
  30         if(num) {
  31                 if(!(mode & 0x04)) val &= ~0x20;
  32                 if(!(mode & 0x08)) val &= ~0x10;
  33                 dir = ((mode & 0x20) == 0);
  34         } else {
  35                 if(!(mode & 0x01)) val &= ~0x20;
  36                 if(!(mode & 0x02)) val &= ~0x10;
  37                 dir = ((mode & 0x10) == 0);
  38         }
  39
  40         // direction
  41         if(dir) {
  42                 if(joy_stat[num] & 0x08) val &= ~0x08;
  43                 if(joy_stat[num] & 0x04) val &= ~0x04;
  44                 if(joy_stat[num] & 0x02) val &= ~0x02;
  45                 if(joy_stat[num] & 0x01) val &= ~0x01;
  46         }
  47
  48         // trigger
  49         if(joy_stat[num] & 0x10) val &= ~0x20;
  50         if(joy_stat[num] & 0x20) val &= ~0x10;
  51         return val;
  52 }
  53
  54 #define STATE_VERSION   2
  55
  56 bool JOYSTICK::process_state(FILEIO* state_fio, bool loading)
  57 {
  58         if(!state_fio->StateCheckUint32(STATE_VERSION)) {
  59                 return false;
  60         }
  61         if(!state_fio->StateCheckInt32(this_device_id)) {
  62                 return false;
  63         }
  64         state_fio->StateUint32(mode);
  65         return true;
  66 }