diff options
Diffstat (limited to 'src/devices/bus/einstein/pipe/silicon_disc.cpp')
-rw-r--r-- | src/devices/bus/einstein/pipe/silicon_disc.cpp | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/src/devices/bus/einstein/pipe/silicon_disc.cpp b/src/devices/bus/einstein/pipe/silicon_disc.cpp new file mode 100644 index 00000000000..354ada1c594 --- /dev/null +++ b/src/devices/bus/einstein/pipe/silicon_disc.cpp @@ -0,0 +1,119 @@ +// license: GPL-2.0+ +// copyright-holders: Dirk Best +/*************************************************************************** + + Silicon Disc + +***************************************************************************/ + +#include "emu.h" +#include "silicon_disc.h" + + +//************************************************************************** +// DEVICE DEFINITIONS +//************************************************************************** + +DEFINE_DEVICE_TYPE(EINSTEIN_SILICON_DISC, einstein_silicon_disc_device, "einstein_sd", "Einstein Silicon Disc") + +//------------------------------------------------- +// device_address_map +//------------------------------------------------- + +DEVICE_ADDRESS_MAP_START(map, 8, einstein_silicon_disc_device) + AM_RANGE(0x08, 0x08) AM_MIRROR(0xff00) AM_WRITE(sector_low_w) + AM_RANGE(0x09, 0x09) AM_MIRROR(0xff00) AM_WRITE(sector_high_w) +ADDRESS_MAP_END + +//------------------------------------------------- +// rom_region - device-specific ROM region +//------------------------------------------------- + +ROM_START( silicon_disc ) + ROM_REGION(0x2000, "rom", 0) + ROM_LOAD("sd11.bin", 0x0000, 0x2000, CRC(0e4f5e6d) SHA1(d0bc01e533d8963c596154435c5b2d156a96d470)) +ROM_END + +const tiny_rom_entry *einstein_silicon_disc_device::device_rom_region() const +{ + return ROM_NAME( silicon_disc ); +} + + +//************************************************************************** +// LIVE DEVICE +//************************************************************************** + +//------------------------------------------------- +// einstein_silicon_disc_device - constructor +//------------------------------------------------- + +einstein_silicon_disc_device::einstein_silicon_disc_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : + device_t(mconfig, EINSTEIN_SILICON_DISC, tag, owner, clock), + device_tatung_pipe_interface(mconfig, *this), + m_rom(*this, "rom"), + m_bios(*this, ":bios"), + m_sector(0) +{ +} + +//------------------------------------------------- +// device_start - device-specific startup +//------------------------------------------------- + +void einstein_silicon_disc_device::device_start() +{ + // setup ram + m_ram = std::make_unique<uint8_t[]>(0x40000); + memset(m_ram.get(), 0xff, 0x40000); + + // register for save states + save_pointer(NAME(m_ram.get()), 0x40000); + save_item(NAME(m_sector)); +} + +//------------------------------------------------- +// device_reset - device-specific reset +//------------------------------------------------- + +void einstein_silicon_disc_device::device_reset() +{ + // copy our rom into the main bios region so it will get picked up by the bank switching + // not really part of the pipe interface cartridge but here for convenience, in reality + // the rom gets put directly onto the main motherboard into the second empty socket + memcpy(m_bios->base() + 0x4000, m_rom->base(), 0x2000); + + // install i/o ports + io_space().install_device(0xf0, 0xff, *this, &einstein_silicon_disc_device::map); + io_space().install_readwrite_handler(0xfa, 0xfa, 0, 0, 0xff00, + read8_delegate(FUNC(einstein_silicon_disc_device::ram_r), this), + write8_delegate(FUNC(einstein_silicon_disc_device::ram_w), this)); +} + + +//************************************************************************** +// IMPLEMENTATION +//************************************************************************** + +WRITE8_MEMBER( einstein_silicon_disc_device::sector_low_w ) +{ + m_sector &= 0xff00; + m_sector |= data; +} + +WRITE8_MEMBER( einstein_silicon_disc_device::sector_high_w ) +{ + m_sector &= 0x00ff; + m_sector |= ((data & 0x07) << 8); +} + +// a8 to a14 are used to specify the byte in a 128-byte sector +READ8_MEMBER( einstein_silicon_disc_device::ram_r ) +{ + return m_ram[(m_sector * 0x80) | ((offset >> 8) & 0x7f)]; +} + +WRITE8_MEMBER( einstein_silicon_disc_device::ram_w ) +{ + m_ram[(m_sector * 0x80) | ((offset >> 8) & 0x7f)] = data; +} |