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-rw-r--r--blastem.c131
1 files changed, 88 insertions, 43 deletions
diff --git a/blastem.c b/blastem.c
index 13afd26..8ea6b01 100644
--- a/blastem.c
+++ b/blastem.c
@@ -235,12 +235,18 @@ m68k_context * sync_components(m68k_context * context, uint32_t address)
m68k_context * vdp_port_write(uint32_t vdp_port, m68k_context * context, uint16_t value)
{
+ if (vdp_port & 0x2700E0) {
+ printf("machine freeze due to write to address %X\n", 0xC00000 | vdp_port);
+ exit(1);
+ }
+ vdp_port &= 0x1F;
//printf("vdp_port write: %X, value: %X, cycle: %d\n", vdp_port, value, context->current_cycle);
sync_components(context, 0);
vdp_context * v_context = context->video_context;
if (vdp_port < 0x10) {
int blocked;
if (vdp_port < 4) {
+ uint32_t before_cycle = v_context->cycles;
while (vdp_data_port_write(v_context, value) < 0) {
while(v_context->flags & FLAG_DMA_RUN) {
vdp_run_dma_done(v_context, mclks_per_frame);
@@ -293,25 +299,46 @@ m68k_context * vdp_port_write(uint32_t vdp_port, m68k_context * context, uint16_
return context;
}
-m68k_context * vdp_port_read(uint32_t vdp_port, m68k_context * context)
+m68k_context * vdp_port_write_b(uint32_t vdp_port, m68k_context * context, uint8_t value)
+{
+ return vdp_port_write(vdp_port, context, value | value << 8);
+}
+
+uint16_t vdp_port_read(uint32_t vdp_port, m68k_context * context)
{
+ if (vdp_port & 0x2700E0) {
+ printf("machine freeze due to read from address %X\n", 0xC00000 | vdp_port);
+ exit(1);
+ }
+ vdp_port &= 0x1F;
+ uint16_t value;
sync_components(context, 0);
vdp_context * v_context = context->video_context;
if (vdp_port < 0x10) {
if (vdp_port < 4) {
- context->value = vdp_data_port_read(v_context);
+ value = vdp_data_port_read(v_context);
} else if(vdp_port < 8) {
- context->value = vdp_control_port_read(v_context);
+ value = vdp_control_port_read(v_context);
} else {
- context->value = vdp_hv_counter_read(v_context);
- //printf("HV Counter: %X at cycle %d\n", context->value, v_context->cycles);
+ value = vdp_hv_counter_read(v_context);
+ //printf("HV Counter: %X at cycle %d\n", value, v_context->cycles);
}
context->current_cycle = v_context->cycles/MCLKS_PER_68K;
} else {
printf("Illegal read from PSG or test register port %X\n", vdp_port);
exit(1);
}
- return context;
+ return value;
+}
+
+uint8_t vdp_port_read_b(uint32_t vdp_port, m68k_context * context)
+{
+ uint16_t value = vdp_port_read(vdp_port, context);
+ if (vdp_port & 1) {
+ return value;
+ } else {
+ return value >> 8;
+ }
}
#define TH 0x40
@@ -351,7 +378,7 @@ void io_data_write(io_port * pad, m68k_context * context, uint8_t value)
pad->output = value;
}
-void io_data_read(io_port * pad, m68k_context * context)
+uint8_t io_data_read(io_port * pad, m68k_context * context)
{
uint8_t control = pad->control | 0x80;
uint8_t th = control & pad->output;
@@ -377,10 +404,11 @@ void io_data_read(io_port * pad, m68k_context * context)
input = pad->input[GAMEPAD_TH0] | 0xC;
}
}
- context->value = ((~input) & (~control)) | (pad->output & control);
+ uint8_t value = ((~input) & (~control)) | (pad->output & control);
/*if (pad->input[GAMEPAD_TH0] || pad->input[GAMEPAD_TH1]) {
- printf ("value: %X\n", context->value);
+ printf ("value: %X\n", value);
}*/
+ return value;
}
uint32_t zram_counter = 0;
@@ -596,8 +624,9 @@ m68k_context * io_write_w(uint32_t location, m68k_context * context, uint16_t va
#define NO_DISK 0x20
uint8_t version_reg = NO_DISK | USA;
-m68k_context * io_read(uint32_t location, m68k_context * context)
+uint8_t io_read(uint32_t location, m68k_context * context)
{
+ uint8_t value;
genesis_context *gen = context->system;
if (location < 0x10000) {
if (busack_cycle <= context->current_cycle) {
@@ -607,15 +636,15 @@ m68k_context * io_read(uint32_t location, m68k_context * context)
if (!(busack==Z80_REQ_BUSY || reset)) {
location &= 0x7FFF;
if (location < 0x4000) {
- context->value = z80_ram[location & 0x1FFF];
+ value = z80_ram[location & 0x1FFF];
} else if (location < 0x6000) {
ym_run(gen->ym, context->current_cycle);
- context->value = ym_read_status(gen->ym);
+ value = ym_read_status(gen->ym);
} else {
- context->value = 0xFF;
+ value = 0xFF;
}
} else {
- context->value = 0xFF;
+ value = 0xFF;
}
} else {
location &= 0x1FFF;
@@ -624,23 +653,24 @@ m68k_context * io_read(uint32_t location, m68k_context * context)
{
case 0x0:
//version bits should be 0 for now since we're not emulating TMSS
- //Not sure about the other bits
- context->value = version_reg;
+ value = version_reg;
break;
case 0x1:
- io_data_read(&gamepad_1, context);
+ value = io_data_read(&gamepad_1, context);
break;
case 0x2:
- io_data_read(&gamepad_2, context);
+ value = io_data_read(&gamepad_2, context);
break;
case 0x3://PORT C Data
break;
case 0x4:
- context->value = gamepad_1.control;
+ value = gamepad_1.control;
break;
case 0x5:
- context->value = gamepad_2.control;
+ value = gamepad_2.control;
break;
+ default:
+ value = 0xFF;
}
} else {
if (location == 0x1100) {
@@ -648,20 +678,22 @@ m68k_context * io_read(uint32_t location, m68k_context * context)
busack = new_busack;
busack_cycle = CYCLE_NEVER;
}
- context->value = Z80_RES_BUSACK || busack;
- dprintf("Byte read of BUSREQ returned %d @ %d (reset: %d, busack: %d, busack_cycle %d)\n", context->value, context->current_cycle, reset, busack, busack_cycle);
+ value = Z80_RES_BUSACK || busack;
+ dprintf("Byte read of BUSREQ returned %d @ %d (reset: %d, busack: %d, busack_cycle %d)\n", value, context->current_cycle, reset, busack, busack_cycle);
} else if (location == 0x1200) {
- context->value = !reset;
+ value = !reset;
} else {
+ value = 0xFF;
printf("Byte read of unknown IO location: %X\n", location);
}
}
}
- return context;
+ return value;
}
-m68k_context * io_read_w(uint32_t location, m68k_context * context)
+uint16_t io_read_w(uint32_t location, m68k_context * context)
{
+ uint16_t value;
genesis_context * gen = context->system;
if (location < 0x10000) {
if (busack_cycle <= context->current_cycle) {
@@ -670,7 +702,6 @@ m68k_context * io_read_w(uint32_t location, m68k_context * context)
}
if (!(busack==Z80_REQ_BUSY || reset)) {
location &= 0x7FFF;
- uint16_t value;
if (location < 0x4000) {
value = z80_ram[location & 0x1FFE];
} else if (location < 0x6000) {
@@ -679,9 +710,9 @@ m68k_context * io_read_w(uint32_t location, m68k_context * context)
} else {
value = 0xFF;
}
- context->value = value | (value << 8);
+ value = value | (value << 8);
} else {
- context->value = 0xFFFF;
+ value = 0xFFFF;
}
} else {
location &= 0x1FFF;
@@ -691,45 +722,47 @@ m68k_context * io_read_w(uint32_t location, m68k_context * context)
case 0x0:
//version bits should be 0 for now since we're not emulating TMSS
//Not sure about the other bits
- context->value = 0;
+ value = version_reg;
break;
case 0x1:
- io_data_read(&gamepad_1, context);
+ value = io_data_read(&gamepad_1, context);
break;
case 0x2:
- io_data_read(&gamepad_2, context);
+ value = io_data_read(&gamepad_2, context);
break;
case 0x3://PORT C Data
break;
case 0x4:
- context->value = gamepad_1.control;
+ value = gamepad_1.control;
break;
case 0x5:
- context->value = gamepad_2.control;
+ value = gamepad_2.control;
break;
case 0x6:
//PORT C Control
- context->value = 0;
+ value = 0;
break;
+ default:
+ value = 0;
}
- context->value = context->value | (context->value << 8);
- //printf("Word read to %X returned %d\n", location, context->value);
+ value = value | (value << 8);
+ //printf("Word read to %X returned %d\n", location, value);
} else {
if (location == 0x1100) {
if (busack_cycle <= context->current_cycle) {
busack = new_busack;
busack_cycle = CYCLE_NEVER;
}
- context->value = (Z80_RES_BUSACK || busack) << 8;
- //printf("Word read of BUSREQ returned %d\n", context->value);
+ value = (Z80_RES_BUSACK || busack) << 8;
+ //printf("Word read of BUSREQ returned %d\n", value);
} else if (location == 0x1200) {
- context->value = (!reset) << 8;
+ value = (!reset) << 8;
} else {
printf("Word read of unknown IO location: %X\n", location);
}
}
}
- return context;
+ return value;
}
z80_context * z80_write_ym(uint16_t location, z80_context * context, uint8_t value)
@@ -1000,7 +1033,19 @@ void init_run_cpu(genesis_context * gen, int debug, FILE * address_log)
m68k_context context;
x86_68k_options opts;
gen->m68k = &context;
- init_x86_68k_opts(&opts);
+ memmap_chunk memmap[] = {
+ {0, 0x400000, 0xFFFFFF, 0, MMAP_READ | MMAP_WRITE, cart,
+ NULL, NULL, NULL, NULL},
+ {0xE00000, 0x1000000, 0xFFFF, 0, MMAP_READ | MMAP_WRITE | MMAP_CODE, ram,
+ NULL, NULL, NULL, NULL},
+ {0xC00000, 0xE00000, 0x1FFFFF, 0, 0, NULL,
+ (read_16_fun)vdp_port_read, (write_16_fun)vdp_port_write,
+ (read_8_fun)vdp_port_read_b, (write_8_fun)vdp_port_write_b},
+ {0xA00000, 0xA12000, 0x1FFFF, 0, 0, NULL,
+ (read_16_fun)io_read_w, (write_16_fun)io_write_w,
+ (read_8_fun)io_read, (write_8_fun)io_write}
+ };
+ init_x86_68k_opts(&opts, memmap, sizeof(memmap)/sizeof(memmap_chunk));
opts.address_log = address_log;
init_68k_context(&context, opts.native_code_map, &opts);
@@ -1068,11 +1113,11 @@ int detect_specific_region(char region)
void detect_region()
{
- if (detect_specific_region('U')) {
+ if (detect_specific_region('U')|| detect_specific_region('B') || detect_specific_region('4')) {
version_reg = NO_DISK | USA;
} else if (detect_specific_region('J')) {
version_reg = NO_DISK | JAP;
- } if (detect_specific_region('E') || detect_specific_region('A') || detect_specific_region('B') || detect_specific_region('4')) {
+ } else if (detect_specific_region('E') || detect_specific_region('A')) {
version_reg = NO_DISK | EUR;
}
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-06-19 15:36:43 +0000