diff options
Diffstat (limited to 'src/devices/bus/c64/sw8k.cpp')
-rw-r--r-- | src/devices/bus/c64/sw8k.cpp | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/src/devices/bus/c64/sw8k.cpp b/src/devices/bus/c64/sw8k.cpp new file mode 100644 index 00000000000..9b0cce8c55d --- /dev/null +++ b/src/devices/bus/c64/sw8k.cpp @@ -0,0 +1,114 @@ +// license:BSD-3-Clause +// copyright-holders:Curt Coder +/********************************************************************** + + C64 switchable 8K cartridge emulation + +**********************************************************************/ + +/* + + 4040 + Fast Hack'em + + PCB Layout + ---------- + + |===========================| + |=| | + |=| SW1 | + |=| ROM0 | + |=| | + |=| | + |=| ROM1 | + |=| | + |=| | + |===========================| + + ROM0,1 - National Semiconductor NMC27C64Q 8Kx8 EPROM + SW1 - ROM selection switch + +*/ + +#include "sw8k.h" + + + +//************************************************************************** +// DEVICE DEFINITIONS +//************************************************************************** + +const device_type C64_SW8K = &device_creator<c64_switchable_8k_cartridge_device>; + + +//------------------------------------------------- +// INPUT_PORTS( c64_easyflash ) +//------------------------------------------------- + +static INPUT_PORTS_START( c64_switchable_8k ) + PORT_START("SW") + PORT_DIPNAME( 0x01, 0x00, "ROM Select" ) + PORT_DIPSETTING( 0x00, "ROM 0" ) + PORT_DIPSETTING( 0x01, "ROM 1" ) +INPUT_PORTS_END + + +//------------------------------------------------- +// input_ports - device-specific input ports +//------------------------------------------------- + +ioport_constructor c64_switchable_8k_cartridge_device::device_input_ports() const +{ + return INPUT_PORTS_NAME( c64_switchable_8k ); +} + + + +//************************************************************************** +// LIVE DEVICE +//************************************************************************** + +//------------------------------------------------- +// c64_switchable_8k_cartridge_device - constructor +//------------------------------------------------- + +c64_switchable_8k_cartridge_device::c64_switchable_8k_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) : + device_t(mconfig, C64_SW8K, "C64 Switchable 8K cartridge", tag, owner, clock, "c64_sw8k", __FILE__), + device_c64_expansion_card_interface(mconfig, *this), + m_sw(*this, "SW") +{ +} + + +//------------------------------------------------- +// device_start - device-specific startup +//------------------------------------------------- + +void c64_switchable_8k_cartridge_device::device_start() +{ +} + + +//------------------------------------------------- +// device_reset - device-specific reset +//------------------------------------------------- + +void c64_switchable_8k_cartridge_device::device_reset() +{ + m_bank = m_sw->read(); +} + + +//------------------------------------------------- +// c64_cd_r - cartridge data read +//------------------------------------------------- + +UINT8 c64_switchable_8k_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]; + } + + return data; +} |