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-rw-r--r--src/mess/machine/c64_magic_formel.c277
1 files changed, 277 insertions, 0 deletions
diff --git a/src/mess/machine/c64_magic_formel.c b/src/mess/machine/c64_magic_formel.c
new file mode 100644
index 00000000000..cb6c78ed5b8
--- /dev/null
+++ b/src/mess/machine/c64_magic_formel.c
@@ -0,0 +1,277 @@
+/**********************************************************************
+
+ Magic Formel cartridge emulation
+
+ Copyright MESS Team.
+ Visit http://mamedev.org for licensing and usage restrictions.
+
+**********************************************************************/
+
+#include "c64_magic_formel.h"
+
+
+
+//**************************************************************************
+// MACROS/CONSTANTS
+//**************************************************************************
+
+#define MC6821_TAG "mc6821"
+
+#define PA4 (m_pb7_ff ? m_ram_oe : 0)
+
+
+//**************************************************************************
+// DEVICE DEFINITIONS
+//**************************************************************************
+
+const device_type C64_MAGIC_FORMEL = &device_creator<c64_magic_formel_cartridge_device>;
+
+
+//-------------------------------------------------
+// pia6821_interface pia_intf
+//-------------------------------------------------
+
+WRITE8_MEMBER( c64_magic_formel_cartridge_device::pia_pa_w )
+{
+ /*
+
+ bit description
+
+ PA0 ROM A13
+ PA1 ROM A14
+ PA2 ROM A15
+ PA3 ROM _OE
+ PA4 RAM _OE
+ PA5
+ PA6
+ PA7
+
+ */
+
+ logerror("PA %02x\n",data);
+ m_rom_bank = data & 0x0f;
+
+ m_rom_oe = BIT(data, 3);
+
+ m_ram_oe = BIT(data, 4);
+}
+
+WRITE8_MEMBER( c64_magic_formel_cartridge_device::pia_pb_w )
+{
+ /*
+
+ bit description
+
+ PB0 RAM A10
+ PB1 RAM A11
+ PB2 RAM A9
+ PB3 RAM A8
+ PB4 RAM A12
+ PB5
+ PB6
+ PB7 ROMH enable
+
+ */
+ logerror("PB %02x\n",data);
+ m_ram_bank = data & 0x1f;
+
+ m_pb7 = BIT(data, 7);
+
+ if (!m_pb7)
+ {
+ m_pb7_ff = 1;
+ }
+}
+
+WRITE_LINE_MEMBER( c64_magic_formel_cartridge_device::pia_cb2_w )
+{
+ if (!state)
+ {
+ m_cb2_ff = 1;
+ }
+}
+
+static const pia6821_interface pia_intf =
+{
+ DEVCB_NULL, // input A
+ DEVCB_NULL, // input B
+ DEVCB_NULL, // input CA1
+ DEVCB_NULL, // input CB1
+ DEVCB_NULL, // input CA2
+ DEVCB_NULL, // input CB2
+ DEVCB_DEVICE_MEMBER(DEVICE_SELF_OWNER, c64_magic_formel_cartridge_device, pia_pa_w), // output A
+ DEVCB_DEVICE_MEMBER(DEVICE_SELF_OWNER, c64_magic_formel_cartridge_device, pia_pb_w), // output B
+ DEVCB_NULL, // output CA2
+ DEVCB_DEVICE_LINE_MEMBER(DEVICE_SELF_OWNER, c64_magic_formel_cartridge_device, pia_cb2_w), // output CB2
+ DEVCB_NULL, // irq A
+ DEVCB_NULL // irq B
+};
+
+
+//-------------------------------------------------
+// MACHINE_CONFIG_FRAGMENT( c64_magic_formel )
+//-------------------------------------------------
+
+static MACHINE_CONFIG_FRAGMENT( c64_magic_formel )
+ MCFG_PIA6821_ADD(MC6821_TAG, pia_intf)
+MACHINE_CONFIG_END
+
+
+//-------------------------------------------------
+// machine_config_additions - device-specific
+// machine configurations
+//-------------------------------------------------
+
+machine_config_constructor c64_magic_formel_cartridge_device::device_mconfig_additions() const
+{
+ return MACHINE_CONFIG_NAME( c64_magic_formel );
+}
+
+
+//-------------------------------------------------
+// INPUT_PORTS( c64_magic_formel )
+//-------------------------------------------------
+
+INPUT_CHANGED_MEMBER( c64_magic_formel_cartridge_device::freeze )
+{
+ if (!newval && (m_pb7_ff & m_cb2_ff))
+ {
+ m_cb2_ff = 0;
+
+ m_slot->nmi_w(ASSERT_LINE);
+ }
+ else
+ {
+ m_slot->nmi_w(CLEAR_LINE);
+ }
+}
+
+static INPUT_PORTS_START( c64_magic_formel )
+ PORT_START("FREEZE")
+ PORT_BIT( 0x01, IP_ACTIVE_LOW, IPT_SPECIAL ) PORT_NAME("Freeze") PORT_CHANGED_MEMBER(DEVICE_SELF, c64_magic_formel_cartridge_device, freeze, 0)
+INPUT_PORTS_END
+
+
+//-------------------------------------------------
+// input_ports - device-specific input ports
+//-------------------------------------------------
+
+ioport_constructor c64_magic_formel_cartridge_device::device_input_ports() const
+{
+ return INPUT_PORTS_NAME( c64_magic_formel );
+}
+
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// c64_magic_formel_cartridge_device - constructor
+//-------------------------------------------------
+
+c64_magic_formel_cartridge_device::c64_magic_formel_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) :
+ device_t(mconfig, C64_MAGIC_FORMEL, "C64 Magic Formel cartridge", tag, owner, clock),
+ device_c64_expansion_card_interface(mconfig, *this),
+ m_pia(*this, MC6821_TAG),
+ m_rom_bank(0),
+ m_ram_bank(0),
+ m_pb7_ff(0),
+ m_cb2_ff(0),
+ m_rom_oe(0),
+ m_ram_oe(0),
+ m_pb7(1)
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void c64_magic_formel_cartridge_device::device_start()
+{
+ // state saving
+ save_item(NAME(m_rom_bank));
+ save_item(NAME(m_ram_bank));
+ save_item(NAME(m_pb7_ff));
+ save_item(NAME(m_cb2_ff));
+ save_item(NAME(m_rom_oe));
+ save_item(NAME(m_ram_oe));
+ save_item(NAME(m_pb7));
+}
+
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void c64_magic_formel_cartridge_device::device_reset()
+{
+ m_rom_bank = 0;
+ m_ram_bank = 0;
+ m_pb7_ff = 0;
+ m_cb2_ff = 0;
+ m_rom_oe = 0;
+ m_ram_oe = 0;
+ m_pb7 = 1;
+}
+
+
+//-------------------------------------------------
+// c64_cd_r - cartridge data read
+//-------------------------------------------------
+
+UINT8 c64_magic_formel_cartridge_device::c64_cd_r(address_space &space, offs_t offset, int ba, int roml, int romh, int io1, int io2)
+{
+ UINT8 data = 0;
+
+ if (!romh && !m_rom_oe)
+ {
+ UINT8 bank = m_pb7_ff ? m_rom_bank : 0;
+ offs_t addr = (bank << 13) | (offset & 0x1fff);
+ data = m_romh[addr];
+ }
+ else if (!io1 && !PA4)
+ {
+ offs_t addr = (m_ram_bank << 8) | (offset & 0xff);
+ data = m_ram[addr];
+ }
+
+ return data;
+}
+
+
+//-------------------------------------------------
+// c64_cd_w - cartridge data write
+//-------------------------------------------------
+
+void c64_magic_formel_cartridge_device::c64_cd_w(address_space &space, offs_t offset, UINT8 data, int ba, int roml, int romh, int io1, int io2)
+{
+ if (!io1)
+ {
+ offs_t addr = (m_ram_bank << 8) | (offset & 0xff);
+ m_ram[addr] = data;
+ }
+ else if (!io2 && !(m_cb2_ff & PA4))
+ {
+ offs_t addr = (offset >> 6) & 0x03;
+ UINT8 new_data = (BIT(data, 1) << 7) | (offset & 0x3f);
+ m_pia->write(space, addr, new_data);
+ }
+ else if (offset == 0x0001)
+ {
+ m_pb7_ff = 0;
+ }
+}
+
+
+//-------------------------------------------------
+// c64_game_r - GAME read
+//-------------------------------------------------
+
+int c64_magic_formel_cartridge_device::c64_game_r(offs_t offset, int ba, int rw, int hiram)
+{
+ return !(ba & rw & ((offset & 0xe000) == 0xe000) & !(m_pb7 & m_cb2_ff));
+}