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-rw-r--r--src/devices/bus/a2bus/a2hsscsi.cpp323
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diff --git a/src/devices/bus/a2bus/a2hsscsi.cpp b/src/devices/bus/a2bus/a2hsscsi.cpp
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+// 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 "a2hsscsi.h"
+#include "includes/apple2.h"
+#include "machine/nscsi_cd.h"
+#include "machine/nscsi_hd.h"
+
+/***************************************************************************
+ PARAMETERS
+***************************************************************************/
+
+//**************************************************************************
+// GLOBAL VARIABLES
+//**************************************************************************
+
+const device_type A2BUS_HSSCSI = &device_creator<a2bus_hsscsi_device>;
+
+#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, 0, false)
+ MCFG_NSCSI_ADD("scsibus:1", hsscsi_devices, 0, false)
+ MCFG_NSCSI_ADD("scsibus:2", hsscsi_devices, 0, false)
+ MCFG_NSCSI_ADD("scsibus:3", hsscsi_devices, 0, false)
+ MCFG_NSCSI_ADD("scsibus:4", hsscsi_devices, 0, false)
+ MCFG_NSCSI_ADD("scsibus:5", hsscsi_devices, 0, 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 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 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)
+{
+}
+
+a2bus_hsscsi_device::a2bus_hsscsi_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 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)
+{
+}
+
+//-------------------------------------------------
+// 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 a2bus_hsscsi_device::read_c0nx(address_space &space, UINT8 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 offset, UINT8 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 a2bus_hsscsi_device::read_cnxx(address_space &space, UINT8 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 offset, UINT8 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 a2bus_hsscsi_device::read_c800(address_space &space, UINT16 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 offset, UINT8 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);
+}