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Diffstat (limited to 'src/devices/bus/msx/slot/panasonic08.cpp')
-rw-r--r--src/devices/bus/msx/slot/panasonic08.cpp132
1 files changed, 132 insertions, 0 deletions
diff --git a/src/devices/bus/msx/slot/panasonic08.cpp b/src/devices/bus/msx/slot/panasonic08.cpp
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+++ b/src/devices/bus/msx/slot/panasonic08.cpp
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+// license:BSD-3-Clause
+// copyright-holders:Wilbert Pol
+/*
+
+ Emulation of the firmware mapper as found in Panasonic FS-A1WX andFS-A1WSX machines.
+
+TODO:
+- SRAM has only 2 4KB pages
+- SRAM is not accessible at 4000-7fff?
+*/
+
+#include "emu.h"
+#include "panasonic08.h"
+
+
+DEFINE_DEVICE_TYPE(MSX_SLOT_PANASONIC08, msx_slot_panasonic08_device, "msx_slot_panasonic08", "MSX Internal Panasonic08")
+
+
+msx_slot_panasonic08_device::msx_slot_panasonic08_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
+ : device_t(mconfig, MSX_SLOT_PANASONIC08, tag, owner, clock)
+ , msx_internal_slot_interface(mconfig, *this)
+ , m_nvram(*this, "nvram")
+ , m_rom_region(*this, finder_base::DUMMY_TAG)
+ , m_bank(*this, "bank%u", 0U)
+ , m_view{ {*this, "view0"}, {*this, "view1"}, {*this, "view2"}, {*this, "view3"}, {*this, "view4"}, {*this, "view5"} }
+ , m_region_offset(0)
+ , m_control(0)
+{
+}
+
+void msx_slot_panasonic08_device::device_add_mconfig(machine_config &config)
+{
+ NVRAM(config, m_nvram, nvram_device::DEFAULT_ALL_0);
+}
+
+void msx_slot_panasonic08_device::device_start()
+{
+ // Sanity checks
+ if (m_rom_region->bytes() < m_region_offset + 0x200000)
+ {
+ fatalerror("Memory region '%s' is too small for the panasonic08 firmware\n", m_rom_region.finder_tag());
+ }
+
+ m_sram.resize(SRAM_SIZE);
+
+ m_nvram->set_base(&m_sram[0], SRAM_SIZE);
+
+ save_item(NAME(m_selected_bank));
+ save_item(NAME(m_control));
+
+ for (int i = 0; i < 6; i++)
+ {
+ m_bank[i]->configure_entries(0, 0x100, m_rom_region->base() + m_region_offset, 0x2000);
+ m_bank[i]->configure_entry(0x80, m_sram.data());
+ m_bank[i]->configure_entry(0x81, m_sram.data() + 0x2000);
+ m_bank[i]->configure_entry(0x82, m_sram.data());
+ m_bank[i]->configure_entry(0x83, m_sram.data() + 0x2000);
+ }
+
+ page(0)->install_view(0x0000, 0x1fff, m_view[0]);
+ m_view[0][0].install_read_bank(0x0000, 0x1fff, m_bank[0]);
+ m_view[0][1].install_readwrite_bank(0x0000, 0x1fff, m_bank[0]);
+
+ page(0)->install_view(0x2000, 0x3fff, m_view[1]);
+ m_view[1][0].install_read_bank(0x2000, 0x3fff, m_bank[1]);
+ m_view[1][1].install_readwrite_bank(0x2000, 0x3fff, m_bank[1]);
+
+ // no sram writing in 4000-7fff?
+ page(1)->install_read_bank(0x4000, 0x5fff, m_bank[2]);
+
+ page(1)->install_view(0x6000, 0x7fff, m_view[3]);
+ m_view[3][0].install_read_bank(0x6000, 0x7fff, m_bank[3]);
+ m_view[3][1].install_read_bank(0x6000, 0x7fff, m_bank[3]);
+ m_view[3][1].install_read_handler(0x7ff0, 0x7ff7, emu::rw_delegate(*this, FUNC(msx_slot_panasonic08_device::bank_r)));
+ page(1)->install_write_handler(0x6000, 0x6000, emu::rw_delegate(*this, FUNC(msx_slot_panasonic08_device::bank_w<0>)));
+ page(1)->install_write_handler(0x6400, 0x6400, emu::rw_delegate(*this, FUNC(msx_slot_panasonic08_device::bank_w<1>)));
+ page(1)->install_write_handler(0x6800, 0x6800, emu::rw_delegate(*this, FUNC(msx_slot_panasonic08_device::bank_w<2>)));
+ page(1)->install_write_handler(0x6c00, 0x6c00, emu::rw_delegate(*this, FUNC(msx_slot_panasonic08_device::bank_w<3>)));
+ page(1)->install_write_handler(0x7000, 0x7000, emu::rw_delegate(*this, FUNC(msx_slot_panasonic08_device::bank_w<4>)));
+ page(1)->install_write_handler(0x7800, 0x7800, emu::rw_delegate(*this, FUNC(msx_slot_panasonic08_device::bank_w<5>)));
+ page(1)->install_write_handler(0x7ff9, 0x7ff9, emu::rw_delegate(*this, FUNC(msx_slot_panasonic08_device::control_w)));
+
+ page(2)->install_view(0x8000, 0x9fff, m_view[4]);
+ m_view[4][0].install_read_bank(0x8000, 0x9fff, m_bank[4]);
+ m_view[4][1].install_readwrite_bank(0x8000, 0x9fff, m_bank[4]);
+
+ page(2)->install_view(0xa000, 0xbfff, m_view[5]);
+ m_view[5][0].install_read_bank(0xa000, 0xbfff, m_bank[5]);
+ m_view[5][1].install_readwrite_bank(0xa000, 0xbfff, m_bank[5]);
+}
+
+void msx_slot_panasonic08_device::device_reset()
+{
+ m_control = 0;
+ for (int i = 0 ; i < 6; i++)
+ {
+ m_selected_bank[i] = 0;
+ m_bank[i]->set_entry(0);
+ if (i != 2)
+ m_view[i].select(0);
+ }
+}
+
+template <int Bank>
+void msx_slot_panasonic08_device::set_view()
+{
+ bool ram_active = (m_selected_bank[Bank] >= 0x80 && m_selected_bank[Bank] < 0x84);
+ if (Bank == 3)
+ m_view[3].select(BIT(m_control, 2) ? 1 : 0);
+ else if (Bank != 2)
+ m_view[Bank].select(ram_active ? 1 : 0);
+}
+
+template <int Bank>
+void msx_slot_panasonic08_device::bank_w(u8 data)
+{
+ m_selected_bank[Bank] = data;
+ m_bank[Bank]->set_entry(data);
+ set_view<Bank>();
+}
+
+u8 msx_slot_panasonic08_device::bank_r(offs_t offset)
+{
+ return (offset < 6) ? m_selected_bank[offset] : 0;
+}
+
+void msx_slot_panasonic08_device::control_w(u8 data)
+{
+ // writing $04 enables read back of banking registers at 7ff0-7ff5
+ m_control = data;
+ set_view<3>();
+}