summaryrefslogtreecommitdiffstatshomepage
path: root/src/devices/bus/gameboy
diff options
context:
space:
mode:
author Miodrag Milanovic <mmicko@gmail.com>2016-06-29 08:34:30 +0200
committer Miodrag Milanovic <mmicko@gmail.com>2016-06-29 08:34:30 +0200
commit63f9a01f8c5d43b9cfe68c2d401a84647d19c10e (patch)
treea1f1874aa84850bddbebd2b0e0bfc3e1c77ce8c4 /src/devices/bus/gameboy
parent1f6f1bfd6cfb748d9c5e159d6bd014bab8d30944 (diff)
Cleanup and version bumpmame0175
Diffstat (limited to 'src/devices/bus/gameboy')
-rw-r--r--src/devices/bus/gameboy/mbc.cpp33
-rw-r--r--src/devices/bus/gameboy/mbc.h2
2 files changed, 17 insertions, 18 deletions
diff --git a/src/devices/bus/gameboy/mbc.cpp b/src/devices/bus/gameboy/mbc.cpp
index 3192bcda9ce..cf5a6f44a98 100644
--- a/src/devices/bus/gameboy/mbc.cpp
+++ b/src/devices/bus/gameboy/mbc.cpp
@@ -452,7 +452,7 @@ void gb_rom_mbc3_device::update_rtc()
{
system_time curtime;
machine().current_datetime(curtime);
-
+
m_rtc_regs[0] = curtime.local_time.second;
m_rtc_regs[1] = curtime.local_time.minute;
m_rtc_regs[2] = curtime.local_time.hour;
@@ -700,7 +700,7 @@ WRITE8_MEMBER(gb_rom_m161_device::write_bank)
{
// the mapper (74HC161A) only has data lines D2..D0
data &= 0x07;
-
+
// A15 is connected to #LOAD and overwritten by QD (m_load_disable)
switch (offset & 0x8000)
{
@@ -719,31 +719,30 @@ WRITE8_MEMBER(gb_rom_m161_device::write_bank)
READ8_MEMBER(gb_rom_mmm01_device::read_rom)
{
-
UINT16 romb = m_romb & ~m_romb_nwe;
UINT16 romb_base = m_romb & (0x1e0 | m_romb_nwe);
UINT8 ramb_masked = ((offset & 0x4000) | m_mode ? m_ramb : m_ramb & ~0x03);
-
+
// zero-adjust RA18..RA14
romb = (romb ? romb : 0x01);
// if unmapped, force
romb = (m_map ? romb : 0x01);
-
+
// RB 0 logic
if (!(offset & 0x4000))
romb = 0x00;
-
+
// combine with base
romb |= romb_base;
-
+
// multiplex with AA14..AA13
if (m_mux)
romb = (romb & ~0x60) | ((ramb_masked & 0x03) << 5);
-
+
// if unmapped, force
if (!m_map)
romb |= 0x1fe;
-
+
return m_rom[rom_bank_map[romb] * 0x4000 + (offset & 0x3fff)];
}
@@ -751,7 +750,7 @@ WRITE8_MEMBER(gb_rom_mmm01_device::write_bank)
{
// the mapper only has data lines D6..D0
data &= 0x7f;
-
+
// the mapper only uses inputs A15..A13
switch (offset & 0xe000)
{
@@ -765,7 +764,7 @@ WRITE8_MEMBER(gb_rom_mmm01_device::write_bank)
case 0x2000: // RA20..RA19 RA18..RA14
if (!m_map)
m_romb = (m_romb & ~0x60) | (data & 0x60);
-
+
m_romb = (m_romb & (~0x1f | m_romb_nwe)) | (data & (0x1f & ~m_romb_nwe));
break;
case 0x4000: // Mode #WE, RA22..RA21, AA16..AA15, AA14..AA13
@@ -774,7 +773,7 @@ WRITE8_MEMBER(gb_rom_mmm01_device::write_bank)
m_romb = (m_romb & ~0x180) | ((data & 0x30) << 3);
m_ramb = (m_ramb & ~0x0c) | (data & 0x0c);
}
-
+
m_ramb = (m_ramb & (~0x03 | m_ramb_nwe)) | (data & (0x03 & ~m_ramb_nwe));
break;
case 0x6000: // Mux, RA18..RA15 #WE/Mask, ???, MBC1 Mode
@@ -783,7 +782,7 @@ WRITE8_MEMBER(gb_rom_mmm01_device::write_bank)
// m_romb_nwe is aligned to RA14, hence >> 1 instead of >> 2
m_romb_nwe = (data & 0x3c) >> 1;
}
-
+
if (!m_mode_nwe)
m_mode = data & 0x01;
break;
@@ -796,11 +795,11 @@ READ8_MEMBER(gb_rom_mmm01_device::read_ram)
{
UINT8 ramb_masked = ((offset & 0x4000) | m_mode ? m_ramb : m_ramb & ~0x03);
UINT8 ramb = ramb_masked;
-
+
// multiplex with RA20..RA19
if (m_mux)
ramb = (ramb & ~0x03) | ((m_romb & 0x60) >> 5);
-
+
if (!m_ram.empty() && m_ram_enable)
{
return m_ram[ram_bank_map[ramb] * 0x2000 + (offset & 0x1fff)];
@@ -813,11 +812,11 @@ WRITE8_MEMBER(gb_rom_mmm01_device::write_ram)
{
UINT8 ramb_masked = ((offset & 0x4000) | m_mode ? m_ramb : m_ramb & ~0x03);
UINT8 ramb = ramb_masked;
-
+
// multiplex with RA20..RA19
if (m_mux)
ramb = (ramb & ~0x03) | ((m_romb & 0x60) >> 5);
-
+
if (!m_ram.empty() && m_ram_enable)
{
m_ram[ram_bank_map[ramb] * 0x2000 + (offset & 0x1fff)] = data;
diff --git a/src/devices/bus/gameboy/mbc.h b/src/devices/bus/gameboy/mbc.h
index 1dcc43875bd..827d42c392d 100644
--- a/src/devices/bus/gameboy/mbc.h
+++ b/src/devices/bus/gameboy/mbc.h
@@ -195,7 +195,7 @@ public:
virtual DECLARE_WRITE8_MEMBER(write_bank) override;
virtual DECLARE_READ8_MEMBER(read_ram) override;
virtual DECLARE_WRITE8_MEMBER(write_ram) override;
-
+
UINT16 m_romb;
UINT8 m_romb_nwe;
UINT8 m_ramb;