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improved I/O emulation accuracy

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optimized gamepad/teamplayer code
This commit is contained in:
ekeeke31 2010-07-16 08:30:25 +00:00
parent 7a28d34f4d
commit b758b0b57e
4 changed files with 165 additions and 186 deletions
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269
source/gen_input.c
View File

@ -110,10 +110,10 @@ static void lightgun_update(int num)
} }
/* Sega Menacer specific */ /* Sega Menacer specific */
uint32 menacer_read(void) unsigned int menacer_read(void)
{ {
/* pins should return 0 by default (fix Body Count when mouse is enabled) */ /* pins should return 0 by default (fix Body Count when mouse is enabled) */
int retval = 0x00; unsigned int retval = 0x00;
if (input.pad[4] & INPUT_B) retval |= 0x01; if (input.pad[4] & INPUT_B) retval |= 0x01;
if (input.pad[4] & INPUT_A) retval |= 0x02; if (input.pad[4] & INPUT_A) retval |= 0x02;
if (input.pad[4] & INPUT_C) retval |= 0x04; if (input.pad[4] & INPUT_C) retval |= 0x04;
@ -123,11 +123,11 @@ uint32 menacer_read(void)
} }
/* Konami Justifier specific */ /* Konami Justifier specific */
uint32 justifier_read(void) unsigned int justifier_read(void)
{ {
/* TL & TR pins should always return 1 (write only) */ /* TL & TR pins should always return 1 (write only) */
/* LEFT & RIGHT pins should always return 0 (needed during gun detection) */ /* LEFT & RIGHT pins should always return 0 (needed during gun detection) */
int retval = 0x73; unsigned int retval = 0x73;
switch (io_reg[2]) switch (io_reg[2])
{ {
@ -169,7 +169,7 @@ static inline void mouse_reset(void)
mouse.Port = (input.system[0] == SYSTEM_MOUSE) ? 0 : 4; mouse.Port = (input.system[0] == SYSTEM_MOUSE) ? 0 : 4;
} }
void mouse_write(uint32 data) void mouse_write(unsigned int data)
{ {
if (mouse.Counter == 0) if (mouse.Counter == 0)
{ {
@ -199,9 +199,9 @@ void mouse_write(uint32 data)
mouse.State = data; mouse.State = data;
} }
uint32 mouse_read() unsigned int mouse_read()
{ {
int temp = 0x00; unsigned int temp = 0x00;
switch (mouse.Counter) switch (mouse.Counter)
{ {
@ -282,30 +282,33 @@ static struct pad
uint8 Delay; uint8 Delay;
} gamepad[MAX_DEVICES]; } gamepad[MAX_DEVICES];
static inline void gamepad_raz(uint32 i) static inline void gamepad_raz(int i)
{ {
gamepad[i].Counter = 0; gamepad[i].Counter = 0;
gamepad[i].Delay = 0; gamepad[i].Delay = 0;
} }
static inline void gamepad_reset(uint32 i) static inline void gamepad_reset(int i)
{ {
gamepad[i].State = 0x40; gamepad[i].State = 0x00;
if (input.dev[i] == DEVICE_6BUTTON) gamepad_raz(i); if (input.dev[i] == DEVICE_6BUTTON) gamepad_raz(i);
} }
static inline void gamepad_update(uint32 i) static inline void gamepad_update(int i)
{ {
if (gamepad[i].Delay++ > 25) gamepad_raz(i); if (gamepad[i].Delay++ > 25) gamepad_raz(i);
} }
static inline uint32 gamepad_read(uint32 i) static inline unsigned int gamepad_read(int i)
{ {
/* bit7 is latched */ /* bit7 is latched */
int retval = 0x7F; unsigned int retval = 0x7F;
/* pad status */
unsigned int pad = input.pad[i];
/* current TH state */ /* current TH state */
int control = (gamepad[i].State & 0x40) >> 6; unsigned int control = (gamepad[i].State & 0x40) >> 6;
/* TH transitions counter */ /* TH transitions counter */
if (input.dev[i] == DEVICE_6BUTTON) if (input.dev[i] == DEVICE_6BUTTON)
@ -318,23 +321,16 @@ static inline uint32 gamepad_read(uint32 i)
case 5: /*** Third High ***/ case 5: /*** Third High ***/
/* TH = 1 : ?1CBRLDU */ /* TH = 1 : ?1CBRLDU */
if (input.pad[i] & INPUT_C) retval &= ~0x20; retval &= ~(pad & 0x3F);
if (input.pad[i] & INPUT_B) retval &= ~0x10;
if (input.pad[i] & INPUT_UP) retval &= ~0x01;
if (input.pad[i] & INPUT_DOWN) retval &= ~0x02;
if (input.pad[i] & INPUT_LEFT) retval &= ~0x04;
if (input.pad[i] & INPUT_RIGHT) retval &= ~0x08;
break; break;
case 0: /*** First low ***/ case 0: /*** First low ***/
case 2: /*** Second low ***/ case 2: /*** Second low ***/
/* TH = 0 : ?0SA00DU */ /* TH = 0 : ?0SA00DU */
if (input.pad[i] & INPUT_A) retval &= ~0x10; retval &= ~(pad & 0x03);
if (input.pad[i] & INPUT_START) retval &= ~0x20; retval &= ~((pad >> 2) & 0x30);
if (input.pad[i] & INPUT_UP) retval &= ~0x01; retval &= ~0x0C;
if (input.pad[i] & INPUT_DOWN) retval &= ~0x02;
retval &= 0xB3;
break; break;
/* 6buttons specific (taken from gen-hw.txt) */ /* 6buttons specific (taken from gen-hw.txt) */
@ -352,28 +348,21 @@ static inline uint32 gamepad_read(uint32 i)
case 4: /*** Third Low ***/ case 4: /*** Third Low ***/
/* TH = 0 : ?0SA0000 D3-0 are forced to '0'*/ /* TH = 0 : ?0SA0000 D3-0 are forced to '0'*/
if (input.pad[i] & INPUT_A) retval &= ~0x10; retval &= ~((pad >> 2) & 0x30);
if (input.pad[i] & INPUT_START) retval &= ~0x20; retval &= ~0x0F;
retval &= 0xB0;
break; break;
case 6: /*** Fourth Low ***/ case 6: /*** Fourth Low ***/
/* TH = 0 : ?0SA1111 D3-0 are forced to '1'*/ /* TH = 0 : ?0SA1111 D3-0 are forced to '1'*/
if (input.pad[i] & INPUT_A) retval &= ~0x10; retval &= ~((pad >> 2) & 0x30);
if (input.pad[i] & INPUT_START) retval &= ~0x20;
retval &= 0xBF;
break; break;
case 7: /*** Fourth High ***/ case 7: /*** Fourth High ***/
/* TH = 1 : ?1CBMXYZ Extra buttons returned in D3-0*/ /* TH = 1 : ?1CBMXYZ Extra buttons returned in D3-0*/
if (input.pad[i] & INPUT_X) retval &= ~0x04; retval &= ~(pad & 0x30);
if (input.pad[i] & INPUT_Y) retval &= ~0x02; retval &= ~((pad >> 8) & 0x0F);
if (input.pad[i] & INPUT_Z) retval &= ~0x01;
if (input.pad[i] & INPUT_B) retval &= ~0x10;
if (input.pad[i] & INPUT_C) retval &= ~0x20;
if (input.pad[i] & INPUT_MODE) retval &= ~0x08;
break; break;
default: default:
@ -383,7 +372,7 @@ static inline uint32 gamepad_read(uint32 i)
return retval; return retval;
} }
static inline void gamepad_write(uint32 i, uint32 data) static inline void gamepad_write(int i, unsigned int data)
{ {
if (input.dev[i] == DEVICE_6BUTTON) if (input.dev[i] == DEVICE_6BUTTON)
{ {
@ -394,7 +383,6 @@ static inline void gamepad_write(uint32 i, uint32 data)
gamepad[i].Delay = 0; gamepad[i].Delay = 0;
} }
} }
gamepad[i].State = data; gamepad[i].State = data;
} }
@ -410,132 +398,113 @@ static struct teamplayer
uint8 Table[12]; uint8 Table[12];
} teamplayer[2]; } teamplayer[2];
static inline void teamplayer_init(uint32 port) static inline void teamplayer_init(int port)
{ {
int i; int i,padnum;
int index = 0; int index = 0;
int pad_input = 0;
/* this table determines which gamepad input should be returned during acquisition sequence /* this table determines which gamepad input should be returned during acquisition sequence
index = teamplayer read table index: 0=1st read, 1=2nd read, ... index = teamplayer read table index: 0=1st read, 1=2nd read, ...
pad_input = gamepad input 0-14: 0=P1_DIR, 1=P1_SABC, 2=P1_MXYZ, 4=P2_DIR, 5=P2_SABC, ... table = high bits are pad index, low bits are pad input shift: 0=RLDU, 4=SABC, 8=MXYZ
*/ */
for (i=0; i<4; i++) for (i=0; i<4; i++)
{ {
if (input.dev[(4*port) + i] == DEVICE_3BUTTON) padnum = (4 * port) + i;
if (input.dev[padnum] == DEVICE_3BUTTON)
{ {
teamplayer[port].Table[index++] = pad_input; padnum = padnum << 4;
teamplayer[port].Table[index++] = pad_input + 1; teamplayer[port].Table[index++] = padnum;
teamplayer[port].Table[index++] = padnum | 4;
} }
else if (input.dev[(4*port) + i] == DEVICE_6BUTTON) else if (input.dev[(4*port) + i] == DEVICE_6BUTTON)
{ {
teamplayer[port].Table[index++] = pad_input; padnum = padnum << 4;
teamplayer[port].Table[index++] = pad_input + 1; teamplayer[port].Table[index++] = padnum;
teamplayer[port].Table[index++] = pad_input + 2; teamplayer[port].Table[index++] = padnum | 4;
teamplayer[port].Table[index++] = padnum | 8;
} }
pad_input += 4;
} }
} }
static inline void teamplayer_reset(uint32 port) static inline void teamplayer_reset(int port)
{ {
teamplayer[port].State = 0x60; /* TH = 1, TR = 1 */ teamplayer[port].State = 0x60; /* TH = 1, TR = 1 */
teamplayer[port].Counter = 0; teamplayer[port].Counter = 0;
} }
/* SEGA teamplayer returns successively: static inline unsigned int teamplayer_read(int port)
- PAD1 inputs
- PAD2 inputs
- PAD3 inputs
- PAD4 inputs
Each PAD inputs is obtained through 2 or 3 sequential reads:
1/ DIR buttons
2/ START,A,C,B buttons
3/ MODE, X,Y,Z buttons (6Button only !)
*/
static inline uint32 teamplayer_read_device(uint32 port, uint32 index)
{ {
int retval = 0x7F; unsigned int counter = teamplayer[port].Counter;
int pad_input = teamplayer[port].Table[index] & 0x03;
int pad_num = (4 * port) + ((teamplayer[port].Table[index] >> 2) & 0x03);
switch (pad_input) /* acquisition sequence */
switch (counter)
{ {
case 0: case 0: /* initial state: TH = 1, TR = 1 -> RLDU = 0011 */
/* Directions Buttons */ {
if (input.pad[pad_num] & INPUT_UP) retval &= ~0x01; return 0x73;
if (input.pad[pad_num] & INPUT_DOWN) retval &= ~0x02; }
if (input.pad[pad_num] & INPUT_LEFT) retval &= ~0x04;
if (input.pad[pad_num] & INPUT_RIGHT) retval &= ~0x08;
break;
case 1: case 1: /* start request: TH = 0, TR = 1 -> RLDU = 1111 */
/* S,A,C,B Buttons */ {
if (input.pad[pad_num] & INPUT_B) retval &= ~0x01; return 0x3F;
if (input.pad[pad_num] & INPUT_C) retval &= ~0x02; }
if (input.pad[pad_num] & INPUT_A) retval &= ~0x04;
if (input.pad[pad_num] & INPUT_START) retval &= ~0x08;
break;
case 2: case 2:
/* M,X,Y,Z Buttons (6-Buttons only)*/ case 3: /* ack request: TH=0, TR=0/1 -> RLDU = 0000 */
if (input.pad[pad_num] & INPUT_Z) retval &= ~0x01; {
if (input.pad[pad_num] & INPUT_Y) retval &= ~0x02; /* TL should match TR */
if (input.pad[pad_num] & INPUT_X) retval &= ~0x04; return ((teamplayer[port].State & 0x20) >> 1);
if (input.pad[pad_num] & INPUT_MODE) retval &= ~0x08; }
break;
}
return retval;
}
static inline uint32 teamplayer_read(uint32 port)
{
int retval = 0x7F;
int padnum;
switch (teamplayer[port].Counter) /* acquisition sequence steps */
{
case 0: /* initial state: TH = 1, TR = 1 */
retval = 0x73;
break;
case 1: /* start request: TH = 0, TR = 1 */
retval = 0x3F;
break;
case 2:
case 3: /* ack request: TH=0, TR handshake */
retval = 0x00;
break;
case 4: case 4:
case 5: case 5:
case 6: case 6:
case 7: /* gamepads type */ case 7: /* PAD type */
padnum = (4 * port) + teamplayer[port].Counter - 4; {
retval = input.dev[padnum]; unsigned int retval = input.dev[(port << 2) + (counter - 4)];
break;
default: /* gamepads inputs acquisition */ /* TL should match TR */
retval = teamplayer_read_device(port, teamplayer[port].Counter - 8); return (((teamplayer[port].State & 0x20) >> 1) | retval);
break; }
default: /* PAD status */
{
unsigned int retval = 0x0F;
/* SEGA teamplayer returns successively PAD1 -> PAD2 -> PAD3 -> PAD4 inputs */
unsigned int padnum = teamplayer[port].Table[counter - 8] >> 4;
/* Each PAD inputs is obtained through 2 or 3 sequential reads: RLDU -> SACB -> MXYZ */
retval &= ~(input.pad[padnum] >> (teamplayer[port].Table[counter - 8] & 0x0F));
/* TL should match TR */
return (((teamplayer[port].State & 0x20) >> 1) | retval);
}
} }
/* TL must match TR state */
retval &= ~0x10;
if (teamplayer[port].State & 0x20) retval |= 0x10;
return retval;
} }
static inline void teamplayer_write(uint32 port, uint32 data) static inline void teamplayer_write(int port, unsigned int data)
{ {
int old_state = teamplayer[port].State; /* update output bits only */
teamplayer[port].State = (data & io_reg[port+4]) | (teamplayer[port].State & ~io_reg[port+4]); unsigned int state = (teamplayer[port].State & ~io_reg[port + 4]) | (data & io_reg[port + 4]);
if (old_state != teamplayer[port].State) teamplayer[port].Counter ++;
if ((data&0x60) == 0x60) teamplayer[port].Counter = 0; /* TH & TR handshaking */
if ((teamplayer[port].State ^ state) & 0x60)
{
if (state & 0x40)
{
/* TH high -> reset counter */
teamplayer[port].Counter = 0;
}
else
{
/* increment counter */
teamplayer[port].Counter ++;
}
/* update internal state */
teamplayer[port].State = state;
}
} }
/***************************************************************************** /*****************************************************************************
@ -547,15 +516,15 @@ static struct wayplay
uint8 current; uint8 current;
} wayplay; } wayplay;
static inline void wayplay_write(uint32 port, uint32 data) static inline void wayplay_write(int port, unsigned int data)
{ {
if (port == 0) gamepad_write(wayplay.current, data); if (!port && (io_reg[4] & 0x40)) gamepad_write(wayplay.current, data);
else wayplay.current = (data >> 4) & 0x07; else wayplay.current = (data >> 4) & 0x07;
} }
static inline uint32 wayplay_read(uint32 port) static inline unsigned int wayplay_read(int port)
{ {
if (port == 1) return 0x7F; if (port) return 0x7F;
if (wayplay.current >= 4) return 0x70; /* multitap detection (TH2 = 1) */ if (wayplay.current >= 4) return 0x70; /* multitap detection (TH2 = 1) */
return gamepad_read(wayplay.current); /* 0x0C = Pad1, 0x1C = Pad2, ... */ return gamepad_read(wayplay.current); /* 0x0C = Pad1, 0x1C = Pad2, ... */
} }
@ -565,73 +534,73 @@ static inline uint32 wayplay_read(uint32 port)
* I/O wrappers * I/O wrappers
* *
*****************************************************************************/ *****************************************************************************/
uint32 gamepad_1_read (void) unsigned int gamepad_1_read (void)
{ {
return gamepad_read(0); return gamepad_read(0);
} }
uint32 gamepad_2_read (void) unsigned int gamepad_2_read (void)
{ {
return gamepad_read(4); return gamepad_read(4);
} }
void gamepad_1_write (uint32 data) void gamepad_1_write (unsigned int data)
{ {
gamepad_write(0, data); if (io_reg[4] & 0x40) gamepad_write(0, data);
} }
void gamepad_2_write (uint32 data) void gamepad_2_write (unsigned int data)
{ {
gamepad_write(4, data); if (io_reg[5] & 0x40) gamepad_write(4, data);
} }
uint32 wayplay_1_read (void) unsigned int wayplay_1_read (void)
{ {
return wayplay_read(0); return wayplay_read(0);
} }
uint32 wayplay_2_read (void) unsigned int wayplay_2_read (void)
{ {
return wayplay_read(1); return wayplay_read(1);
} }
void wayplay_1_write (uint32 data) void wayplay_1_write (unsigned int data)
{ {
wayplay_write(0, data); wayplay_write(0, data);
} }
void wayplay_2_write (uint32 data) void wayplay_2_write (unsigned int data)
{ {
wayplay_write(1, data); wayplay_write(1, data);
} }
uint32 teamplayer_1_read (void) unsigned int teamplayer_1_read (void)
{ {
return teamplayer_read(0); return teamplayer_read(0);
} }
uint32 teamplayer_2_read (void) unsigned int teamplayer_2_read (void)
{ {
return teamplayer_read(1); return teamplayer_read(1);
} }
void teamplayer_1_write (uint32 data) void teamplayer_1_write (unsigned int data)
{ {
teamplayer_write(0, data); teamplayer_write(0, data);
} }
void teamplayer_2_write (uint32 data) void teamplayer_2_write (unsigned int data)
{ {
teamplayer_write(1, data); teamplayer_write(1, data);
} }
uint32 jcart_read(uint32 address) unsigned int jcart_read(unsigned int address)
{ {
/* TH2 (output) fixed to 0 on read (fixes Micro Machines 2) */ /* TH2 (output) fixed to 0 on read (fixes Micro Machines 2) */
return (gamepad_read(5) | ((gamepad_read(6)&0x3f) << 8)); return (gamepad_read(5) | ((gamepad_read(6)&0x3f) << 8));
} }
void jcart_write(uint32 address, uint32 data) void jcart_write(unsigned int address, unsigned int data)
{ {
gamepad_write(5, (data&1) << 6); gamepad_write(5, (data&1) << 6);
gamepad_write(6, (data&1) << 6); gamepad_write(6, (data&1) << 6);

14
source/gen_input.h
View File

@ -37,15 +37,15 @@
/* Input bitmasks */ /* Input bitmasks */
#define INPUT_MODE (0x0800) #define INPUT_MODE (0x0800)
#define INPUT_Z (0x0400) #define INPUT_X (0x0400)
#define INPUT_Y (0x0200) #define INPUT_Y (0x0200)
#define INPUT_X (0x0100) #define INPUT_Z (0x0100)
#define INPUT_START (0x0080) #define INPUT_START (0x0080)
#define INPUT_C (0x0040) #define INPUT_A (0x0040)
#define INPUT_B (0x0020) #define INPUT_C (0x0020)
#define INPUT_A (0x0010) #define INPUT_B (0x0010)
#define INPUT_LEFT (0x0008) #define INPUT_RIGHT (0x0008)
#define INPUT_RIGHT (0x0004) #define INPUT_LEFT (0x0004)
#define INPUT_DOWN (0x0002) #define INPUT_DOWN (0x0002)
#define INPUT_UP (0x0001) #define INPUT_UP (0x0001)

64
source/gen_io.c
View File

@ -28,10 +28,19 @@ uint8 region_code = REGION_USA;
static struct port_t static struct port_t
{ {
void (*data_w)(uint32 data); void (*data_w)(unsigned int data);
uint32 (*data_r)(void); unsigned int (*data_r)(void);
} port[3]; } port[3];
static void dummy_write(unsigned int data)
{
}
static unsigned int dummy_read(void)
{
return 0x7F;
}
/***************************************************************************** /*****************************************************************************
* I/O chip functions * * I/O chip functions *
* * * *
@ -62,8 +71,8 @@ void io_init(void)
break; break;
default: default:
port[0].data_w = NULL; port[0].data_w = dummy_write;
port[0].data_r = NULL; port[0].data_r = dummy_read;
break; break;
} }
@ -80,12 +89,12 @@ void io_init(void)
break; break;
case SYSTEM_MENACER: case SYSTEM_MENACER:
port[1].data_w = NULL; port[1].data_w = dummy_write;
port[1].data_r = menacer_read; port[1].data_r = menacer_read;
break; break;
case SYSTEM_JUSTIFIER: case SYSTEM_JUSTIFIER:
port[1].data_w = NULL; port[1].data_w = dummy_write;
port[1].data_r = justifier_read; port[1].data_r = justifier_read;
break; break;
@ -100,14 +109,14 @@ void io_init(void)
break; break;
default: default:
port[1].data_w = NULL; port[1].data_w = dummy_write;
port[1].data_r = NULL; port[1].data_r = dummy_read;
break; break;
} }
/* External Port (unconnected) */ /* External Port (unconnected) */
port[2].data_w = NULL; port[2].data_w = dummy_write;
port[2].data_r = NULL; port[2].data_r = dummy_read;
/* Initialize connected input devices */ /* Initialize connected input devices */
input_init(); input_init();
@ -118,9 +127,9 @@ void io_reset(void)
{ {
/* Reset I/O registers */ /* Reset I/O registers */
io_reg[0x00] = region_code | 0x20 | (config.tmss & 1); io_reg[0x00] = region_code | 0x20 | (config.tmss & 1);
io_reg[0x01] = 0x7F; io_reg[0x01] = 0x00;
io_reg[0x02] = 0x7F; io_reg[0x02] = 0x00;
io_reg[0x03] = 0x7F; io_reg[0x03] = 0x00;
io_reg[0x04] = 0x00; io_reg[0x04] = 0x00;
io_reg[0x05] = 0x00; io_reg[0x05] = 0x00;
io_reg[0x06] = 0x00; io_reg[0x06] = 0x00;
@ -138,35 +147,37 @@ void io_reset(void)
input_reset(); input_reset();
} }
void io_write(uint32 offset, uint32 value) void io_write(unsigned int offset, unsigned int data)
{ {
switch (offset) switch (offset)
{ {
case 0x01: /* Port A Data */ case 0x01: /* Port A Data */
case 0x02: /* Port B Data */ case 0x02: /* Port B Data */
case 0x03: /* Port C Data */ case 0x03: /* Port C Data */
io_reg[offset] = value & (0x80 | io_reg[offset+3]); io_reg[offset] = data;
if(port[offset-1].data_w) port[offset-1].data_w(data);
port[offset-1].data_w(value);
return; return;
case 0x04: /* Port A Ctrl */ case 0x04: /* Port A Ctrl */
case 0x05: /* Port B Ctrl */ case 0x05: /* Port B Ctrl */
case 0x06: /* Port C Ctrl */ case 0x06: /* Port C Ctrl */
io_reg[offset] = value; if (data != io_reg[offset])
io_reg[offset-3] &= (0x80 | value); {
io_reg[offset] = data;
port[offset-4].data_w(io_reg[offset-3]);
}
return; return;
case 0x07: /* Port A TxData */ case 0x07: /* Port A TxData */
case 0x0A: /* Port B TxData */ case 0x0A: /* Port B TxData */
case 0x0D: /* Port C TxData */ case 0x0D: /* Port C TxData */
io_reg[offset] = value; io_reg[offset] = data;
return; return;
case 0x09: /* Port A S-Ctrl */ case 0x09: /* Port A S-Ctrl */
case 0x0C: /* Port B S-Ctrl */ case 0x0C: /* Port B S-Ctrl */
case 0x0F: /* Port C S-Ctrl */ case 0x0F: /* Port C S-Ctrl */
io_reg[offset] = value & 0xF8; io_reg[offset] = data & 0xF8;
return; return;
default: /* Read-only ports */ default: /* Read-only ports */
@ -174,7 +185,7 @@ void io_write(uint32 offset, uint32 value)
} }
} }
uint32 io_read(uint32 offset) unsigned int io_read(unsigned int offset)
{ {
switch(offset) switch(offset)
{ {
@ -182,13 +193,12 @@ uint32 io_read(uint32 offset)
case 0x02: /* Port B Data */ case 0x02: /* Port B Data */
case 0x03: /* Port C Data */ case 0x03: /* Port C Data */
{ {
uint8 input = 0x7F; unsigned int mask = 0x80 | io_reg[offset + 3];
if(port[offset-1].data_r) unsigned int data = port[offset-1].data_r();
input = port[offset-1].data_r(); return (io_reg[offset] & mask) | (data & ~mask);
return (io_reg[offset] | ((~io_reg[offset+3]) & input));
} }
default: /* return register value */ default: /* return register value */
return (io_reg[offset]); return io_reg[offset];
} }
} }

4
source/gen_io.h
View File

@ -37,8 +37,8 @@ extern int old_system[2];
/* Function prototypes */ /* Function prototypes */
extern void io_init(void); extern void io_init(void);
extern void io_reset(void); extern void io_reset(void);
extern void io_write(uint32 offset, uint32 value); extern void io_write(unsigned int offset, unsigned int data);
extern uint32 io_read(uint32 offset); extern unsigned int io_read(unsigned int offset);
#endif /* _IO_H_ */ #endif /* _IO_H_ */