// license:BSD-3-Clause // copyright-holders:R. Belmont /********************************************************************* a2hsscsi.c Implementation of the Apple II High Speed SCSI Card This uses an ASIC called "Sandwich II"; the card itself is sometimes known as "Cocoon". Notes: C0n0-C0n7 = NCR5380 registers in normal order C0n8 = DMA address low C0n9 = DMA address high C0nA = DMA count low C0nB = DMA count high C0nC = DMA control C0nD = Enable DMA / reset 5380 C0nE = Priority (read bits 5-7) / Fire watchdog (write bit 7) / RAM bank (write bits 0-3) C0nF = DMA speed (bit 7 = 0 for fast, 1 for slow) / ROM bank (write bits 0-4) DMA control register (C0nC): 0x01 = pseudo-DMA enable 0x02 = DMA enable 0x04 = test mode 0x08 = disable stop-DMA-on-IRQ 0x10 = DMA direction (read only) 0x20 = 5380 IRQ enable 0x40 = system DMA status (read only) 0x80 = DMA stopped due to IRQ Enable DMA / reset 5380 register (C0nD): 0x01 = Resume DMA after rollover or IRQ 0x02 = Reset the 5380 0x40 = Clear test mode 0x80 = Set test mode *********************************************************************/ #include "emu.h" #include "a2hsscsi.h" #include "machine/nscsi_cd.h" #include "machine/nscsi_hd.h" /*************************************************************************** PARAMETERS ***************************************************************************/ //************************************************************************** // GLOBAL VARIABLES //************************************************************************** const device_type A2BUS_HSSCSI = &device_creator; #define SCSI_ROM_REGION "scsi_rom" #define SCSI_BUS_TAG "scsibus" #define SCSI_5380_TAG "scsibus:7:ncr5380" static MACHINE_CONFIG_FRAGMENT( ncr5380 ) MCFG_DEVICE_CLOCK(10000000) MCFG_NCR5380N_DRQ_HANDLER(DEVWRITELINE("^^", a2bus_hsscsi_device, drq_w)) MACHINE_CONFIG_END static SLOT_INTERFACE_START( hsscsi_devices ) SLOT_INTERFACE("cdrom", NSCSI_CDROM) SLOT_INTERFACE("harddisk", NSCSI_HARDDISK) SLOT_INTERFACE_INTERNAL("ncr5380", NCR5380N) SLOT_INTERFACE_END static MACHINE_CONFIG_FRAGMENT( hsscsi ) MCFG_NSCSI_BUS_ADD(SCSI_BUS_TAG) MCFG_NSCSI_ADD("scsibus:0", hsscsi_devices, nullptr, false) MCFG_NSCSI_ADD("scsibus:1", hsscsi_devices, nullptr, false) MCFG_NSCSI_ADD("scsibus:2", hsscsi_devices, nullptr, false) MCFG_NSCSI_ADD("scsibus:3", hsscsi_devices, nullptr, false) MCFG_NSCSI_ADD("scsibus:4", hsscsi_devices, nullptr, false) MCFG_NSCSI_ADD("scsibus:5", hsscsi_devices, nullptr, false) MCFG_NSCSI_ADD("scsibus:6", hsscsi_devices, "harddisk", false) MCFG_NSCSI_ADD("scsibus:7", hsscsi_devices, "ncr5380", true) MCFG_DEVICE_CARD_MACHINE_CONFIG("ncr5380", ncr5380) MACHINE_CONFIG_END ROM_START( hsscsi ) ROM_REGION(0x8000, SCSI_ROM_REGION, 0) ROM_LOAD( "341-0803.bin", 0x0000, 0x8000, CRC(2c15618b) SHA1(7d32227299933bfc1b7f8bc2062906fdfe530674) ) ROM_END /*************************************************************************** FUNCTION PROTOTYPES ***************************************************************************/ //------------------------------------------------- // machine_config_additions - device-specific // machine configurations //------------------------------------------------- machine_config_constructor a2bus_hsscsi_device::device_mconfig_additions() const { return MACHINE_CONFIG_NAME( hsscsi ); } //------------------------------------------------- // rom_region - device-specific ROM region //------------------------------------------------- const tiny_rom_entry *a2bus_hsscsi_device::device_rom_region() const { return ROM_NAME( hsscsi ); } //************************************************************************** // LIVE DEVICE //************************************************************************** a2bus_hsscsi_device::a2bus_hsscsi_device(const machine_config &mconfig, device_type type, const char *name, const char *tag, device_t *owner, uint32_t clock, const char *shortname, const char *source) : device_t(mconfig, type, name, tag, owner, clock, shortname, source), device_a2bus_card_interface(mconfig, *this), m_ncr5380(*this, SCSI_5380_TAG), m_scsibus(*this, SCSI_BUS_TAG), m_rom(nullptr), m_rambank(0), m_rombank(0), m_drq(0), m_bank(0), m_816block(false), m_c0ne(0), m_c0nf(0) { } a2bus_hsscsi_device::a2bus_hsscsi_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock) : device_t(mconfig, A2BUS_HSSCSI, "Apple II High-Speed SCSI Card", tag, owner, clock, "a2hsscsi", __FILE__), device_a2bus_card_interface(mconfig, *this), m_ncr5380(*this, SCSI_5380_TAG), m_scsibus(*this, SCSI_BUS_TAG), m_rom(nullptr), m_rambank(0), m_rombank(0), m_drq(0), m_bank(0), m_816block(false), m_c0ne(0), m_c0nf(0) { } //------------------------------------------------- // device_start - device-specific startup //------------------------------------------------- void a2bus_hsscsi_device::device_start() { // set_a2bus_device makes m_slot valid set_a2bus_device(); m_rom = device().machine().root_device().memregion(this->subtag(SCSI_ROM_REGION).c_str())->base(); memset(m_ram, 0, 8192); save_item(NAME(m_ram)); save_item(NAME(m_rambank)); save_item(NAME(m_rombank)); save_item(NAME(m_bank)); save_item(NAME(m_drq)); save_item(NAME(m_816block)); } void a2bus_hsscsi_device::device_reset() { m_rambank = 0; m_rombank = 0; m_c0ne = m_c0nf = 0; m_816block = false; } /*------------------------------------------------- read_c0nx - called for reads from this card's c0nx space -------------------------------------------------*/ uint8_t a2bus_hsscsi_device::read_c0nx(address_space &space, uint8_t offset) { switch (offset) { case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: // printf("Read 5380 @ %x\n", offset); return m_ncr5380->read(space, offset); case 0xc: return 0x00; // indicate watchdog? case 0xe: // code at cf32 wants to RMW this without killing the ROM bank return m_c0ne; case 0xf: return m_c0nf; default: printf("Read c0n%x (PC=%x)\n", offset, space.device().safe_pc()); break; } return 0xff; } /*------------------------------------------------- write_c0nx - called for writes to this card's c0nx space -------------------------------------------------*/ void a2bus_hsscsi_device::write_c0nx(address_space &space, uint8_t offset, uint8_t data) { switch (offset) { case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7: // printf("%02x to 5380 reg %x\n", data, offset); m_ncr5380->write(space, offset, data); break; #if 0 case 8: // DMA address low break; case 9: // DMA address high break; case 0xa: // DMA count low break; case 0xb: // DMA count high break; case 0xc: // DMA control break; #endif case 0xd: // DMA enable / reset printf("%02x to DMA enable/reset\n", data); if (data & 0x2) { // printf("Resetting SCSI: %02x at %x\n", data, space.device().safe_pc()); m_ncr5380->reset(); } break; case 0xe: m_c0ne = data; m_rombank = (data & 0x1f) * 0x400; printf("c0ne to %x (ROM bank %x)\n", data & 0x1f, m_rombank); break; case 0xf: m_c0nf = data; m_rambank = (data & 0x7) * 0x400; printf("c0nf to %x (RAM bank %x)\n", data & 0x7, m_rambank); break; default: printf("Write %02x to c0n%x (PC=%x)\n", data, offset, space.device().safe_pc()); break; } } /*------------------------------------------------- read_cnxx - called for reads from this card's cnxx space -------------------------------------------------*/ uint8_t a2bus_hsscsi_device::read_cnxx(address_space &space, uint8_t offset) { // one slot image at the start of the ROM, it appears return m_rom[offset]; } void a2bus_hsscsi_device::write_cnxx(address_space &space, uint8_t offset, uint8_t data) { // printf("Write %02x to cn%02x (PC=%x)\n", data, offset, space.device().safe_pc()); } /*------------------------------------------------- read_c800 - called for reads from this card's c800 space -------------------------------------------------*/ uint8_t a2bus_hsscsi_device::read_c800(address_space &space, uint16_t offset) { // bankswitched RAM at c800-cbff // bankswitched ROM at cc00-cfff if (offset < 0x400) { // printf("Read RAM at %x = %02x\n", offset+m_rambank, m_ram[offset + m_rambank]); if (m_816block) { return m_ncr5380->dma_r(); } return m_ram[offset + m_rambank]; } else { return m_rom[(offset-0x400) + m_rombank]; } } /*------------------------------------------------- write_c800 - called for writes to this card's c800 space -------------------------------------------------*/ void a2bus_hsscsi_device::write_c800(address_space &space, uint16_t offset, uint8_t data) { if (offset < 0x400) { // printf("%02x to RAM at %x\n", data, offset+m_rambank); if (m_816block) { m_ncr5380->dma_w(data); } else { m_ram[offset + m_rambank] = data; } } } WRITE_LINE_MEMBER( a2bus_hsscsi_device::drq_w ) { m_drq = (state ? 0x80 : 0x00); }