diff options
Diffstat (limited to 'src/devices/bus/msx_cart/fs_sr022.c')
-rw-r--r-- | src/devices/bus/msx_cart/fs_sr022.c | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/src/devices/bus/msx_cart/fs_sr022.c b/src/devices/bus/msx_cart/fs_sr022.c new file mode 100644 index 00000000000..c3aee7b9b81 --- /dev/null +++ b/src/devices/bus/msx_cart/fs_sr022.c @@ -0,0 +1,71 @@ +// license:BSD-3-Clause +// copyright-holders:Wilbert Pol +#include "emu.h" +#include "fs_sr022.h" + + +const device_type MSX_CART_FS_SR022 = &device_creator<msx_cart_fs_sr022>; + + +msx_cart_fs_sr022::msx_cart_fs_sr022(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) + : device_t(mconfig, MSX_CART_FS_SR022, "MSX Cartridge - FS-SR022", tag, owner, clock, "msx_cart_fs_sr022", __FILE__) + , msx_cart_interface(mconfig, *this) + , m_bunsetsu_rom(NULL) + , m_bunsetsu_address(0) +{ +} + + +void msx_cart_fs_sr022::device_start() +{ + save_item(NAME(m_bunsetsu_address)); +} + + +void msx_cart_fs_sr022::device_reset() +{ + m_bunsetsu_address = 0; +} + + +void msx_cart_fs_sr022::initialize_cartridge() +{ + if (get_rom_size() != 0x40000) + { + fatalerror("fs_sr022: Invalid ROM size\n"); + } + m_bunsetsu_rom = get_rom_base() + 0x20000; +} + + +READ8_MEMBER(msx_cart_fs_sr022::read_cart) +{ + if (offset >= 0x4000 && offset < 0xc000) + { + if (offset == 0xbfff) { + return m_bunsetsu_rom[m_bunsetsu_address++ & 0x1ffff]; + } + + return get_rom_base()[offset - 0x4000]; + } + return 0xff; +} + + +WRITE8_MEMBER(msx_cart_fs_sr022::write_cart) +{ + switch (offset) + { + case 0xbffc: + m_bunsetsu_address = (m_bunsetsu_address & 0xffff00) | data; + break; + + case 0xbffd: + m_bunsetsu_address = (m_bunsetsu_address & 0xff00ff) | (data << 8); + break; + + case 0xbffe: + m_bunsetsu_address = (m_bunsetsu_address & 0x00ffff) | (data << 16); + break; + } +} |