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Diffstat (limited to 'src/devices/bus/msx_cart/fs_sr022.c')
-rw-r--r--src/devices/bus/msx_cart/fs_sr022.c71
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;
+ }
+}