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Diffstat (limited to 'src/devices/bus/nes/disksys.cpp')
-rw-r--r--src/devices/bus/nes/disksys.cpp91
1 files changed, 57 insertions, 34 deletions
diff --git a/src/devices/bus/nes/disksys.cpp b/src/devices/bus/nes/disksys.cpp
index 2eae2960536..582f63a3b21 100644
--- a/src/devices/bus/nes/disksys.cpp
+++ b/src/devices/bus/nes/disksys.cpp
@@ -13,8 +13,6 @@
TODO:
- convert floppy drive + fds format to modern code!
- - add sound bits
- - stop IRQ from using HOLD_LINE
***********************************************************************************************************/
@@ -26,12 +24,11 @@
#include "speaker.h"
#ifdef NES_PCB_DEBUG
- #define VERBOSE 1
+#define VERBOSE (LOG_GENERAL)
#else
- #define VERBOSE 0
+#define VERBOSE (0)
#endif
-
-#define LOG_MMC(x) do { if (VERBOSE) logerror x; } while (0)
+#include "logmacro.h"
//-----------------------------------------------
@@ -65,9 +62,9 @@ void nes_disksys_device::device_add_mconfig(machine_config &config)
ROM_START( disksys )
ROM_REGION(0x2000, "drive", 0)
- ROM_SYSTEM_BIOS( 0, "2c33a-01a", "Famicom Disk System Bios")
+ ROM_SYSTEM_BIOS( 0, "2c33a-01a", "Famicom Disk System BIOS")
ROMX_LOAD( "rp2c33a-01a.bin", 0x0000, 0x2000, CRC(5e607dcf) SHA1(57fe1bdee955bb48d357e463ccbf129496930b62), ROM_BIOS(0)) // newer, Nintendo logo has no shadow
- ROM_SYSTEM_BIOS( 1, "2c33-01", "Famicom Disk System Bios, older")
+ ROM_SYSTEM_BIOS( 1, "2c33-01", "Famicom Disk System BIOS, older")
ROMX_LOAD( "rp2c33-01.bin", 0x0000, 0x2000, CRC(1c7ae5d5) SHA1(af5af53f66982e749643fdf8b2acbb7d4d3ed229), ROM_BIOS(1)) // older, Nintendo logo has shadow
ROM_END
@@ -110,7 +107,7 @@ nes_disksys_device::nes_disksys_device(const machine_config &mconfig, const char
, m_disk(*this, "floppy0")
, m_sound(*this, "rp2c33snd")
, irq_timer(nullptr)
- , m_irq_count(0), m_irq_count_latch(0), m_irq_enable(0), m_irq_transfer(0), m_fds_motor_on(0), m_fds_door_closed(0), m_fds_current_side(0), m_fds_head_position(0), m_fds_status0(0), m_read_mode(0), m_drive_ready(0)
+ , m_irq_count(0), m_irq_count_latch(0), m_irq_enable(0), m_irq_repeat(0), m_irq_transfer(0), m_disk_reg_enable(0), m_fds_motor_on(0), m_fds_door_closed(0), m_fds_current_side(0), m_fds_head_position(0), m_fds_status0(0), m_read_mode(0), m_drive_ready(0)
, m_fds_sides(0), m_fds_last_side(0), m_fds_count(0)
{
}
@@ -123,7 +120,7 @@ void nes_disksys_device::device_start()
m_disk->floppy_install_load_proc(nes_disksys_device::load_proc);
m_disk->floppy_install_unload_proc(nes_disksys_device::unload_proc);
- irq_timer = timer_alloc(TIMER_IRQ);
+ irq_timer = timer_alloc(FUNC(nes_disksys_device::irq_timer_tick), this);
irq_timer->adjust(attotime::zero, 0, clocks_to_attotime(1));
save_item(NAME(m_fds_motor_on));
@@ -134,9 +131,11 @@ void nes_disksys_device::device_start()
save_item(NAME(m_read_mode));
save_item(NAME(m_drive_ready));
save_item(NAME(m_irq_enable));
+ save_item(NAME(m_irq_repeat));
save_item(NAME(m_irq_transfer));
save_item(NAME(m_irq_count));
save_item(NAME(m_irq_count_latch));
+ save_item(NAME(m_disk_reg_enable));
save_item(NAME(m_fds_last_side));
save_item(NAME(m_fds_count));
@@ -159,7 +158,9 @@ void nes_disksys_device::pcb_reset()
m_irq_count = 0;
m_irq_count_latch = 0;
m_irq_enable = 0;
+ m_irq_repeat = 0;
m_irq_transfer = 0;
+ m_disk_reg_enable = 0;
m_fds_count = 0;
m_fds_last_side = 0;
@@ -182,7 +183,7 @@ void nes_disksys_device::pcb_reset()
void nes_disksys_device::write_h(offs_t offset, uint8_t data)
{
- LOG_MMC(("Famicom Disk System write_h, offset %04x, data: %02x\n", offset, data));
+ LOG("Famicom Disk System write_h, offset %04x, data: %02x\n", offset, data);
if (offset < 0x6000)
m_prgram[offset + 0x2000] = data;
@@ -190,7 +191,7 @@ void nes_disksys_device::write_h(offs_t offset, uint8_t data)
uint8_t nes_disksys_device::read_h(offs_t offset)
{
- LOG_MMC(("Famicom Disk System read_h, offset: %04x\n", offset));
+ LOG("Famicom Disk System read_h, offset: %04x\n", offset);
if (offset < 0x6000)
return m_prgram[offset + 0x2000];
@@ -200,25 +201,29 @@ uint8_t nes_disksys_device::read_h(offs_t offset)
void nes_disksys_device::write_m(offs_t offset, uint8_t data)
{
- LOG_MMC(("Famicom Disk System write_m, offset: %04x, data: %02x\n", offset, data));
+ LOG("Famicom Disk System write_m, offset: %04x, data: %02x\n", offset, data);
m_prgram[offset] = data;
}
uint8_t nes_disksys_device::read_m(offs_t offset)
{
- LOG_MMC(("Famicom Disk System read_m, offset: %04x\n", offset));
+ LOG("Famicom Disk System read_m, offset: %04x\n", offset);
return m_prgram[offset];
}
-void nes_disksys_device::hblank_irq(int scanline, int vblank, int blanked)
+void nes_disksys_device::hblank_irq(int scanline, bool vblank, bool blanked)
{
+ // FIXME: This looks like a gross hack that ties the disk byte transfer IRQ to the PPU. Seriously?
if (m_irq_transfer)
- hold_irq_line();
+ {
+ set_irq_line(ASSERT_LINE);
+ m_fds_status0 |= 0x02;
+ }
}
void nes_disksys_device::write_ex(offs_t offset, uint8_t data)
{
- LOG_MMC(("Famicom Disk System write_ex, offset: %04x, data: %02x\n", offset, data));
+ LOG("Famicom Disk System write_ex, offset: %04x, data: %02x\n", offset, data);
if (offset >= 0x20 && offset < 0x60)
{
@@ -236,12 +241,25 @@ void nes_disksys_device::write_ex(offs_t offset, uint8_t data)
m_irq_count_latch = (m_irq_count_latch & 0x00ff) | (data << 8);
break;
case 0x02:
- m_irq_count = m_irq_count_latch;
- m_irq_enable = BIT(data, 1);
+ if (m_disk_reg_enable)
+ {
+ m_irq_repeat = BIT(data, 0);
+ m_irq_enable = BIT(data, 1);
+ if (m_irq_enable)
+ m_irq_count = m_irq_count_latch;
+ else
+ set_irq_line(CLEAR_LINE);
+ }
break;
case 0x03:
// bit0 - Enable disk I/O registers
// bit1 - Enable sound I/O registers
+ m_disk_reg_enable = BIT(data, 0);
+ if (!m_disk_reg_enable)
+ {
+ m_irq_enable = 0;
+ set_irq_line(CLEAR_LINE);
+ }
m_sound_en = BIT(data, 1);
break;
case 0x04:
@@ -249,6 +267,9 @@ void nes_disksys_device::write_ex(offs_t offset, uint8_t data)
// TEST!
if (m_fds_data && m_fds_current_side && !m_read_mode)
m_fds_data[(m_fds_current_side - 1) * 65500 + m_fds_head_position++] = data;
+ // clear the byte transfer flag
+ m_fds_status0 &= ~0x02;
+ set_irq_line(CLEAR_LINE);
break;
case 0x05:
// $4025 - FDS Control
@@ -295,7 +316,7 @@ void nes_disksys_device::write_ex(offs_t offset, uint8_t data)
uint8_t nes_disksys_device::read_ex(offs_t offset)
{
- LOG_MMC(("Famicom Disk System read_ex, offset: %04x\n", offset));
+ LOG("Famicom Disk System read_ex, offset: %04x\n", offset);
uint8_t ret = 0x00;
if (offset >= 0x20 && offset < 0x60)
@@ -317,8 +338,9 @@ uint8_t nes_disksys_device::read_ex(offs_t offset)
// bit6 - End of Head (1 when disk head is on the most inner track)
// bit7 - Disk Data Read/Write Enable (1 when disk is readable/writable)
ret = m_fds_status0 | 0x80;
- // clear the disk IRQ detect flag
- m_fds_status0 &= ~0x01;
+ // clear the disk IRQ detect and byte transfer flags
+ m_fds_status0 &= ~0x03;
+ set_irq_line(CLEAR_LINE);
break;
case 0x11:
// $4031 - data latch
@@ -337,6 +359,9 @@ uint8_t nes_disksys_device::read_ex(offs_t offset)
}
else
ret = 0;
+ // clear the byte transfer flag
+ m_fds_status0 &= ~0x02;
+ set_irq_line(CLEAR_LINE);
break;
case 0x12:
// $4032 - disk status 1:
@@ -377,23 +402,22 @@ uint8_t nes_disksys_device::read_ex(offs_t offset)
}
//-------------------------------------------------
-// device_timer - handler timer events
+// irq_timer_tick - handle IRQ timer
//-------------------------------------------------
-void nes_disksys_device::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr)
+TIMER_CALLBACK_MEMBER(nes_disksys_device::irq_timer_tick)
{
- if (id == TIMER_IRQ)
+ if (m_irq_enable)
{
- if (m_irq_enable && m_irq_count)
- {
+ if (m_irq_count)
m_irq_count--;
- if (!m_irq_count)
- {
- hold_irq_line();
+ else
+ {
+ set_irq_line(ASSERT_LINE);
+ m_irq_count = m_irq_count_latch;
+ if (!m_irq_repeat)
m_irq_enable = 0;
- m_fds_status0 |= 0x01;
- m_irq_count_latch = 0; // used in Kaettekita Mario Bros
- }
+ m_fds_status0 |= 0x01;
}
}
}
@@ -433,7 +457,6 @@ void nes_disksys_device::load_disk(device_image_interface &image)
// if there is an header, skip it
image.fseek(header, SEEK_SET);
image.fread(m_fds_data.get(), 65500 * m_fds_sides);
- return;
}
void nes_disksys_device::unload_disk(device_image_interface &image)