Merge pull request #5490 from 68bit/ss30-piaide

SS-30 PIA IDE hard disk interface

scripts/src/bus.lua

@@ -1736,6 +1736,8 @@ if (BUSES["SS50"]~=null) then
 		MAME_DIR .. "src/devices/bus/ss50/mps2.h",
 		MAME_DIR .. "src/devices/bus/ss50/mpt.cpp",
 		MAME_DIR .. "src/devices/bus/ss50/mpt.h",
+		MAME_DIR .. "src/devices/bus/ss50/piaide.cpp",
+		MAME_DIR .. "src/devices/bus/ss50/piaide.h",
 	}
 end
 

src/devices/bus/ss50/interface.cpp

@@ -85,6 +85,7 @@
 #include "bus/ss50/mps.h"
 #include "bus/ss50/mps2.h"
 #include "bus/ss50/mpt.h"
+#include "bus/ss50/piaide.h"
 
 //**************************************************************************
 //  GLOBAL VARIABLES
@@ -225,4 +226,5 @@ void ss50_default_2rs_devices(device_slot_interface &device)
 	device.option_add("mps", SS50_MPS);
 	device.option_add("mps2", SS50_MPS2);
 	device.option_add("mpt", SS50_MPT);
+	device.option_add("piaide", SS50_PIAIDE);
 }

src/devices/bus/ss50/piaide.cpp

@@ -0,0 +1,179 @@
+// license:BSD-3-Clause
+// copyright-holders:68bit
+/**********************************************************************
+
+    PIA IDE Hard Disk Interface
+
+    Note this interface does appear to have used an 8 bit IDE data path, and
+    does appear to have discarded every second byte of storage - this does not
+    appear to be mis-implementation here. FLEX uses 256 byte sectors so half
+    of the IDE 512 byte sector give the required fit.
+
+    Some emulators appear to have stripped out that second unused byte when
+    writing their disk images. So their disk images will need to be filled
+    when importing these images for use with this device. Also some emulators
+    appear tolerant of trailing unused data and their images might need to be
+    truncated to the length defined by the disk geomentry.
+
+    The FLEX drivers for the PIA IDE appear to translate FLEX virtual track
+    and sector ID's into a target geometry. The disk geometry will likely need
+    to be defined and that can be done by using the MAME CHD disk format. The
+    range of FLEX tracks and sectors is limited to 0 to 255 so it needs to use
+    that full virtual range get the largest usable partitions. The drivers
+    support multiple partitions that appears as multiple disks to FLEX to make
+    use of more storage.
+
+    A similar (compatible) interface appears to have been used by the 'PT69'
+    SBC and drivers and disks targeting the PT69 have also run with this
+    device. The 'PT69' appears to place the PIA at 0xe010 to 0xe013 and it's
+    supporting ROM based at 0xf000, in contrast to the MAME swtpc09i machine
+    which places the PIA IDE in IO6 at 0xe060 (so that the DC5 FDC can remain
+    at IO1) and places the supporting ROM at $e800. The MAME swtpc09i machine
+    has booted some PT69 disk images with some minor software changes.
+
+**********************************************************************/
+
+#include "emu.h"
+#include "piaide.h"
+
+#include "machine/6821pia.h"
+#include "machine/idectrl.h"
+
+//**************************************************************************
+//  TYPE DEFINITIONS
+//**************************************************************************
+
+// ======================> ss50_piaide_device
+
+class ss50_piaide_device : public device_t, public ss50_card_interface
+{
+public:
+	// construction/destruction
+	ss50_piaide_device(const machine_config &mconfig, const char *tag, device_t *owner, u32 clock)
+		: device_t(mconfig, SS50_PIAIDE, tag, owner, clock)
+		, ss50_card_interface(mconfig, *this)
+		, m_pia(*this, "pia")
+		, m_ide(*this, "ide")
+	{
+	}
+
+protected:
+	// device-specific overrides
+	virtual void device_add_mconfig(machine_config &config) override;
+	virtual void device_start() override { }
+
+	// interface-specific overrides
+	virtual uint8_t register_read(offs_t offset) override;
+	virtual void register_write(offs_t offset, uint8_t data) override;
+
+private:
+	optional_device<pia6821_device> m_pia;
+	optional_device<ide_controller_device> m_ide;
+
+	uint8_t m_pia_porta;
+	uint8_t m_pia_portb;
+
+	DECLARE_READ8_MEMBER(pia_a_r);
+	DECLARE_READ8_MEMBER(pia_b_r);
+	DECLARE_WRITE8_MEMBER(pia_a_w);
+	DECLARE_WRITE8_MEMBER(pia_b_w);
+
+};
+
+//-------------------------------------------------
+//  device_add_mconfig - add device-specific
+//  machine configuration
+//-------------------------------------------------
+
+void ss50_piaide_device::device_add_mconfig(machine_config &config)
+{
+	PIA6821(config, m_pia, 0);
+	m_pia->readpa_handler().set(FUNC(ss50_piaide_device::pia_a_r));
+	m_pia->readpb_handler().set(FUNC(ss50_piaide_device::pia_b_r));
+	m_pia->writepa_handler().set(FUNC(ss50_piaide_device::pia_a_w));
+	m_pia->writepb_handler().set(FUNC(ss50_piaide_device::pia_b_w));
+
+	IDE_CONTROLLER(config, m_ide).options(ata_devices, "hdd", nullptr, false);
+}
+
+//-------------------------------------------------
+//  register_read - read from a port register
+//-------------------------------------------------
+
+uint8_t ss50_piaide_device::register_read(offs_t offset)
+{
+	return m_pia->read(offset & 3);
+}
+
+//-------------------------------------------------
+//  register_write - write to a port register
+//-------------------------------------------------
+
+void ss50_piaide_device::register_write(offs_t offset, uint8_t data)
+{
+	m_pia->write(offset & 3, data);
+}
+
+/******* MC6821 PIA on IDE Board *******/
+/* Read/Write handlers for pia ide */
+
+READ8_MEMBER( ss50_piaide_device::pia_a_r )
+{
+	return m_pia_porta;
+}
+
+READ8_MEMBER( ss50_piaide_device::pia_b_r )
+{
+	return m_pia_portb;
+}
+
+WRITE8_MEMBER( ss50_piaide_device::pia_a_w )
+{
+	m_pia_porta = data;
+}
+
+WRITE8_MEMBER( ss50_piaide_device::pia_b_w )
+{
+	uint16_t tempidedata;
+
+	m_pia_portb = data;
+
+	// Pass through a 16 bit accessor to the IDE bus.
+	uint8_t low = (data & 0x04) >> 2;
+	uint8_t high = (data & 0x18) >> 3;
+	uint16_t ide_mem_mask = low ? 0xff00 : 0x00ff;
+
+	if ((data & 0x40)&&(!(data&0x20)))  //cs0=0 cs1=1 bit 5&6
+	{
+		if (!(data & 0x02))  //rd line bit 1
+		{
+			tempidedata = m_ide->read_cs0(high, ide_mem_mask);
+			logerror("ide_bus_r: offset $%02X data %04X\n", (data&0x1c)>>2, tempidedata);
+			m_pia_porta = low ? tempidedata >> 8 : tempidedata & 0x00ff;
+		}
+		else if (!(data & 0x01))  //wr line bit 0
+		{
+			uint16_t ide_data = low ? m_pia_porta << 8: m_pia_porta;
+			m_ide->write_cs0(high, ide_data, ide_mem_mask);
+			logerror("ide_bus_w: offset $%02X data %04X\n", (data&0x1c)>>2, m_pia_porta);
+		}
+	}
+	else if ((data & 0x20)&&(!(data&0x40)))  //cs0=1 cs1=0 bit 5&6
+	{
+		if (!(data & 0x02))  //rd line bit 1
+		{
+			tempidedata = m_ide->read_cs1(high, ide_mem_mask);
+			logerror("ide_bus_r: offset $%02X data %04X\n", (data&0x1c)>>2, tempidedata);
+			m_pia_porta = low ? tempidedata >> 8 : tempidedata & 0x00ff;
+		}
+		else if (!(data & 0x01))  //wr line bit 0
+		{
+			uint16_t ide_data = low ? m_pia_porta << 8: m_pia_porta;
+			m_ide->write_cs1(high, ide_data, ide_mem_mask);
+			logerror("ide_bus_w: offset $%02X data %04X\n", (data&0x1c)>>2, m_pia_porta);
+		}
+	}
+}
+
+// device type definition
+DEFINE_DEVICE_TYPE_PRIVATE(SS50_PIAIDE, ss50_card_interface, ss50_piaide_device, "ss50_piaide", "PIA IDE Hard Disk Interface")

src/devices/bus/ss50/piaide.h

@@ -0,0 +1,15 @@
+// license:BSD-3-Clause
+// copyright-holders:68bit
+/**********************************************************************
+
+    PIA IDE Hard Disk Interface
+
+**********************************************************************/
+#ifndef MAME_DEVICE_BUS_SS50_PIAIDE_H
+#define MAME_DEVICE_BUS_SS50_PIAIDE_H
+
+#include "interface.h"
+
+DECLARE_DEVICE_TYPE(SS50_PIAIDE, ss50_card_interface)
+
+#endif // MAME_DEVICE_BUS_SS50_PIAIDE_H