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Diffstat (limited to 'src/devices/bus/odyssey2/rom.c')
-rw-r--r--src/devices/bus/odyssey2/rom.c96
1 files changed, 96 insertions, 0 deletions
diff --git a/src/devices/bus/odyssey2/rom.c b/src/devices/bus/odyssey2/rom.c
new file mode 100644
index 00000000000..2e364e59b9c
--- /dev/null
+++ b/src/devices/bus/odyssey2/rom.c
@@ -0,0 +1,96 @@
+// license:BSD-3-Clause
+// copyright-holders:Fabio Priuli
+/***********************************************************************************************************
+
+
+ Magnavox Odyssey cart emulation
+
+
+ ***********************************************************************************************************/
+
+
+#include "emu.h"
+#include "rom.h"
+
+
+//-------------------------------------------------
+// o2_rom_device - constructor
+//-------------------------------------------------
+
+const device_type O2_ROM_STD = &device_creator<o2_rom_device>;
+const device_type O2_ROM_12K = &device_creator<o2_rom12_device>;
+const device_type O2_ROM_16K = &device_creator<o2_rom16_device>;
+
+
+o2_rom_device::o2_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),
+ device_o2_cart_interface( mconfig, *this )
+{
+}
+
+o2_rom_device::o2_rom_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, O2_ROM_STD, "Odyssey 2 Standard Carts", tag, owner, clock, "o2_rom", __FILE__),
+ device_o2_cart_interface( mconfig, *this )
+{
+}
+
+o2_rom12_device::o2_rom12_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : o2_rom_device(mconfig, O2_ROM_12K, "Odyssey 2 12K Carts", tag, owner, clock, "o2_rom12", __FILE__)
+{
+}
+
+o2_rom16_device::o2_rom16_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : o2_rom_device(mconfig, O2_ROM_16K, "Odyssey 2 16K Carts", tag, owner, clock, "o2_rom16", __FILE__)
+{
+}
+
+
+//-------------------------------------------------
+// device_start/device_reset - device-specific startup
+//-------------------------------------------------
+
+void o2_rom_device::device_start()
+{
+ save_item(NAME(m_bank_base));
+}
+
+void o2_rom_device::device_reset()
+{
+ m_bank_base = 0;
+}
+
+/*-------------------------------------------------
+ mapper specific handlers
+ -------------------------------------------------*/
+
+void o2_rom_device::write_bank(int bank)
+{
+ m_bank_base = bank;
+}
+
+READ8_MEMBER(o2_rom_device::read_rom04)
+{
+ return m_rom[(offset + (m_bank_base & 0x03) * 0x800) & (m_rom_size - 1)];
+}
+READ8_MEMBER(o2_rom_device::read_rom0c)
+{
+ return m_rom[(offset + (m_bank_base & 0x03) * 0x800) & (m_rom_size - 1)];
+}
+
+READ8_MEMBER(o2_rom12_device::read_rom04)
+{
+ return m_rom[offset + (m_bank_base & 0x03) * 0xc00];
+}
+READ8_MEMBER(o2_rom12_device::read_rom0c)
+{
+ return m_rom[offset + 0x800 + (m_bank_base & 0x03) * 0xc00];
+}
+
+READ8_MEMBER(o2_rom16_device::read_rom04)
+{
+ return m_rom[offset + 0x400 + (m_bank_base & 0x03) * 0x1000];
+}
+READ8_MEMBER(o2_rom16_device::read_rom0c)
+{
+ return m_rom[offset + 0xc00 + (m_bank_base & 0x03) * 0x1000];
+}