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Diffstat (limited to 'src/devices/bus/msx/cart/holy_quran.cpp')
-rw-r--r--src/devices/bus/msx/cart/holy_quran.cpp138
1 files changed, 138 insertions, 0 deletions
diff --git a/src/devices/bus/msx/cart/holy_quran.cpp b/src/devices/bus/msx/cart/holy_quran.cpp
new file mode 100644
index 00000000000..74df118b46b
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+++ b/src/devices/bus/msx/cart/holy_quran.cpp
@@ -0,0 +1,138 @@
+// license:BSD-3-Clause
+// copyright-holders:Wilbert Pol
+/******************************************************************************
+
+Al-Alamiah Al-Qur'an Al-Karim
+Only works on Arabian MSXes.
+
+GCMK-16X PCB, 2 ROM chips, Yamaha XE297A0 mapper chip.
+
+******************************************************************************/
+
+#include "emu.h"
+#include "holy_quran.h"
+
+namespace {
+
+class msx_cart_holy_quran_device : public device_t, public msx_cart_interface
+{
+public:
+ msx_cart_holy_quran_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
+ : device_t(mconfig, MSX_CART_HOLY_QURAN, tag, owner, clock)
+ , msx_cart_interface(mconfig, *this)
+ , m_rombank(*this, "rombank%u", 0U)
+ , m_view1(*this, "view1")
+ , m_view2(*this, "view2")
+ { }
+
+ virtual std::error_condition initialize_cartridge(std::string &message) override;
+
+protected:
+ // device_t implementation
+ virtual void device_start() override { }
+ virtual void device_reset() override;
+
+private:
+ static constexpr size_t BANK_SIZE = 0x2000;
+
+ u8 read(offs_t offset);
+ u8 read2(offs_t offset);
+ template <int Bank> void bank_w(u8 data);
+
+ memory_bank_array_creator<4> m_rombank;
+ memory_view m_view1;
+ memory_view m_view2;
+
+ std::vector<u8> m_decrypted;
+ u8 m_bank_mask;
+};
+
+std::error_condition msx_cart_holy_quran_device::initialize_cartridge(std::string &message)
+{
+ if (!cart_rom_region())
+ {
+ message = "msx_cart_holy_quran_device: Required region 'rom' was not found.";
+ return image_error::INTERNAL;
+ }
+
+ const u32 size = cart_rom_region()->bytes();
+ const u16 banks = size / BANK_SIZE;
+
+ if (size > 256 * BANK_SIZE || size < 0x10000 || size != banks * BANK_SIZE || (~(banks - 1) % banks))
+ {
+ message = "msx_cart_holy_quran_device: Region 'rom' has unsupported size.";
+ return image_error::INVALIDLENGTH;
+ }
+
+ m_bank_mask = banks - 1;
+
+ m_decrypted.resize(size);
+
+ // protection uses a simple rotation on databus, some lines inverted
+ u8 *rom = cart_rom_region()->base();
+ for (u32 i = 0; i < size; i++)
+ m_decrypted[i] = bitswap<8>(rom[i],6,2,4,0,1,5,7,3) ^ 0x4d;
+
+ for (int i = 0; i < 4; i++)
+ m_rombank[i]->configure_entries(0, banks, m_decrypted.data(), BANK_SIZE);
+
+ page(1)->install_view(0x4000, 0x7fff, m_view1);
+ m_view1[0].install_read_handler(0x4000, 0x7fff, emu::rw_delegate(*this, FUNC(msx_cart_holy_quran_device::read)));
+ m_view1[1].install_read_bank(0x4000, 0x5fff, m_rombank[0]);
+ m_view1[1].install_read_bank(0x6000, 0x7fff, m_rombank[1]);
+ m_view1[1].install_write_handler(0x5000, 0x5000, emu::rw_delegate(*this, FUNC(msx_cart_holy_quran_device::bank_w<0>)));
+ m_view1[1].install_write_handler(0x5400, 0x5400, emu::rw_delegate(*this, FUNC(msx_cart_holy_quran_device::bank_w<1>)));
+ m_view1[1].install_write_handler(0x5800, 0x5800, emu::rw_delegate(*this, FUNC(msx_cart_holy_quran_device::bank_w<2>)));
+ m_view1[1].install_write_handler(0x5c00, 0x5c00, emu::rw_delegate(*this, FUNC(msx_cart_holy_quran_device::bank_w<3>)));
+
+ page(2)->install_view(0x8000, 0xbfff, m_view2);
+ m_view2[0].install_read_handler(0x8000, 0xbfff, emu::rw_delegate(*this, FUNC(msx_cart_holy_quran_device::read2)));
+ m_view2[1].install_read_bank(0x8000, 0x9fff, m_rombank[2]);
+ m_view2[1].install_read_bank(0xa000, 0xbfff, m_rombank[3]);
+
+ return std::error_condition();
+}
+
+void msx_cart_holy_quran_device::device_reset()
+{
+ m_view1.select(0);
+ m_view2.select(0);
+ for (int i = 0; i < 4; i++)
+ m_rombank[i]->set_entry(0);
+}
+
+u8 msx_cart_holy_quran_device::read(offs_t offset)
+{
+ u8 data = cart_rom_region()->base()[offset];
+ // The decryption should actually start working after the first M1 cycle executing something from the cartridge.
+ if (offset + 0x4000 == ((cart_rom_region()->base()[3] << 8) | cart_rom_region()->base()[2]) && !machine().side_effects_disabled())
+ {
+ // Switch to decrypted contents
+ m_view1.select(1);
+ m_view2.select(1);
+ }
+ return data;
+}
+
+u8 msx_cart_holy_quran_device::read2(offs_t offset)
+{
+ u8 data = cart_rom_region()->base()[offset + 0x4000];
+ // The decryption should actually start working after the first M1 cycle executing something from the cartridge.
+ if (offset + 0x8000 == ((cart_rom_region()->base()[3] << 8) | cart_rom_region()->base()[2]) && !machine().side_effects_disabled())
+ {
+ // Switch to decrypted contents
+ m_view1.select(1);
+ m_view2.select(1);
+ }
+ return data;
+}
+
+template <int Bank>
+void msx_cart_holy_quran_device::bank_w(u8 data)
+{
+ m_rombank[Bank]->set_entry(data & m_bank_mask);
+}
+
+} // anonymous namespace
+
+DEFINE_DEVICE_TYPE_PRIVATE(MSX_CART_HOLY_QURAN, msx_cart_interface, msx_cart_holy_quran_device, "msx_cart_holy_quran", "MSX Cartridge - Holy Quran")