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Diffstat (limited to 'src/emu/bus/c64/system3.c')
-rw-r--r-- | src/emu/bus/c64/system3.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/src/emu/bus/c64/system3.c b/src/emu/bus/c64/system3.c new file mode 100644 index 00000000000..4aeb6c8b459 --- /dev/null +++ b/src/emu/bus/c64/system3.c @@ -0,0 +1,93 @@ +// license:BSD-3-Clause +// copyright-holders:Curt Coder +/********************************************************************** + + System 3 cartridge emulation + + Copyright MESS Team. + Visit http://mamedev.org for licensing and usage restrictions. + +**********************************************************************/ + +#include "system3.h" + + + +//************************************************************************** +// DEVICE DEFINITIONS +//************************************************************************** + +const device_type C64_SYSTEM3 = &device_creator<c64_system3_cartridge_device>; + + + +//************************************************************************** +// LIVE DEVICE +//************************************************************************** + +//------------------------------------------------- +// c64_system3_cartridge_device - constructor +//------------------------------------------------- + +c64_system3_cartridge_device::c64_system3_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) : + device_t(mconfig, C64_SYSTEM3, "C64 System 3 cartridge", tag, owner, clock, "c64_system3", __FILE__), + device_c64_expansion_card_interface(mconfig, *this) +{ +} + + +//------------------------------------------------- +// device_start - device-specific startup +//------------------------------------------------- + +void c64_system3_cartridge_device::device_start() +{ + // state saving + save_item(NAME(m_bank)); +} + + +//------------------------------------------------- +// device_reset - device-specific reset +//------------------------------------------------- + +void c64_system3_cartridge_device::device_reset() +{ + m_bank = 0; +} + + +//------------------------------------------------- +// c64_cd_r - cartridge data read +//------------------------------------------------- + +UINT8 c64_system3_cartridge_device::c64_cd_r(address_space &space, offs_t offset, UINT8 data, int sphi2, int ba, int roml, int romh, int io1, int io2) +{ + if (!roml) + { + offs_t addr = (m_bank << 13) | (offset & 0x1fff); + data = m_roml[addr]; + } + else if (!io1) + { + m_bank = offset & 0x3f; + m_game = 1; + data = 0; + } + + return data; +} + + +//------------------------------------------------- +// c64_cd_w - cartridge data write +//------------------------------------------------- + +void c64_system3_cartridge_device::c64_cd_w(address_space &space, offs_t offset, UINT8 data, int sphi2, int ba, int roml, int romh, int io1, int io2) +{ + if (!io1) + { + m_bank = offset & 0x3f; + m_game = 0; + } +} |