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Diffstat (limited to 'src/devices/bus/msx_slot/rom.c')
-rw-r--r--src/devices/bus/msx_slot/rom.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/src/devices/bus/msx_slot/rom.c b/src/devices/bus/msx_slot/rom.c
new file mode 100644
index 00000000000..609201f60d1
--- /dev/null
+++ b/src/devices/bus/msx_slot/rom.c
@@ -0,0 +1,66 @@
+// license:BSD-3-Clause
+// copyright-holders:Wilbert Pol
+#include "emu.h"
+#include "rom.h"
+
+
+const device_type MSX_SLOT_ROM = &device_creator<msx_slot_rom_device>;
+
+
+msx_slot_rom_device::msx_slot_rom_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, MSX_SLOT_ROM, "MSX Internal ROM", tag, owner, clock, "msx_slot_rom", __FILE__)
+ , msx_internal_slot_interface()
+ , m_region(NULL)
+ , m_region_offset(0)
+ , m_rom(NULL)
+{
+}
+
+
+msx_slot_rom_device::msx_slot_rom_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, UINT32 clock, const char *shortname, const char *source)
+ : device_t(mconfig, type, name, tag, owner, clock, shortname, source)
+ , msx_internal_slot_interface()
+ , m_region(NULL)
+ , m_region_offset(0)
+ , m_rom(NULL)
+{
+}
+
+
+void msx_slot_rom_device::set_rom_start(device_t &device, const char *region, UINT32 offset)
+{
+ msx_slot_rom_device &dev = downcast<msx_slot_rom_device &>(device);
+
+ dev.m_region = region;
+ dev.m_region_offset = offset;
+}
+
+
+void msx_slot_rom_device::device_start()
+{
+ assert(m_region != NULL );
+
+ memory_region *m_rom_region = owner()->memregion(m_region);
+
+ // Sanity checks
+ if (m_rom_region == NULL )
+ {
+ fatalerror("Rom slot '%s': Unable to find memory region '%s'\n", tag(), m_region);
+ }
+ if (m_rom_region->bytes() < m_region_offset + m_size)
+ {
+ fatalerror("Memory region '%s' is too small for rom slot '%s'\n", m_region, tag());
+ }
+
+ m_rom = m_rom_region->base() + m_region_offset;
+}
+
+
+READ8_MEMBER(msx_slot_rom_device::read)
+{
+ if ( offset >= m_start_address && offset < m_end_address )
+ {
+ return m_rom[ offset - m_start_address ];
+ }
+ return 0xFF;
+}