/********************************************************************** Berkeley Softworks GeoRAM emulation Copyright MESS Team. Visit http://mamedev.org for licensing and usage restrictions. **********************************************************************/ #include "c64_georam.h" //************************************************************************** // DEVICE DEFINITIONS //************************************************************************** const device_type C64_GEORAM = &device_creator; //************************************************************************** // LIVE DEVICE //************************************************************************** //------------------------------------------------- // c64_georam_cartridge_device - constructor //------------------------------------------------- c64_georam_cartridge_device::c64_georam_cartridge_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) : device_t(mconfig, C64_GEORAM, "C64 GeoRAM cartridge", tag, owner, clock), device_c64_expansion_card_interface(mconfig, *this) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void c64_georam_cartridge_device::device_start() { // allocate memory c64_ram_pointer(machine(), 0x80000); // state saving save_item(NAME(m_bank)); } //------------------------------------------------- // device_reset - device-specific reset //------------------------------------------------- void c64_georam_cartridge_device::device_reset() { m_bank = 0; } //------------------------------------------------- // c64_cd_r - cartridge data read //------------------------------------------------- UINT8 c64_georam_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 (!io1) { offs_t addr = (m_bank << 8) | (offset & 0xff); data = m_ram[addr]; } return data; } //------------------------------------------------- // c64_cd_w - cartridge data write //------------------------------------------------- void c64_georam_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) { offs_t addr = (m_bank << 8) | (offset & 0xff); m_ram[addr] = data; } else if (!io2) { if (BIT(offset, 0)) { m_bank = ((data & 0x1f) << 6) | (m_bank & 0x3f); } else { m_bank = (m_bank & 0x7c0) | (data & 0x3f); } } }