(MESS) concept: Add 5.25" DSDD raw image support and preliminary pseudo-DMA to buffered controller. [R. Belmont]

.gitattributes

@@ -3723,6 +3723,8 @@ src/lib/formats/coco_dsk.c svneol=native#text/plain
 src/lib/formats/coco_dsk.h svneol=native#text/plain
 src/lib/formats/comx35_dsk.c svneol=native#text/plain
 src/lib/formats/comx35_dsk.h svneol=native#text/plain
+src/lib/formats/concept_dsk.c svneol=native#text/plain
+src/lib/formats/concept_dsk.h svneol=native#text/plain
 src/lib/formats/coupedsk.c svneol=native#text/plain
 src/lib/formats/coupedsk.h svneol=native#text/plain
 src/lib/formats/cpis_dsk.c svneol=native#text/plain

src/emu/bus/a2bus/corvfdc02.c

@@ -5,11 +5,13 @@
     Implemention of the Corvus Systems CORVUS02 floppy controller
     aka the "Buffered Floppy Controller"
  
-    Boot PROM 0.8 says 8" DSDD or 5.25" DSDD
+    Boot PROM 0.8 says 8" SSDD or 5.25" DSDD; we stick with 5.25" here
+    and let the FDC01 handle 8".
  
 *********************************************************************/
 
 #include "corvfdc02.h"
+#include "formats/concept_dsk.h"
 
 /***************************************************************************
     PARAMETERS
@@ -25,11 +27,11 @@ const device_type A2BUS_CORVFDC02 = &device_creator<a2bus_corvfdc02_device>;
 #define FDC02_FDC_TAG		"fdc02_fdc"
 
 FLOPPY_FORMATS_MEMBER( a2bus_corvfdc02_device::corv_floppy_formats )
+	FLOPPY_CONCEPT_525DSDD_FORMAT,
 	FLOPPY_IMD_FORMAT
 FLOPPY_FORMATS_END
 
 static SLOT_INTERFACE_START( corv_floppies )
-	SLOT_INTERFACE( "8dsdd", FLOPPY_8_DSDD )
 	SLOT_INTERFACE( "525dsqd", FLOPPY_525_QD )
 SLOT_INTERFACE_END
 
@@ -121,6 +123,7 @@ void a2bus_corvfdc02_device::device_reset()
 	m_fdc_local_status = 2;
 	m_fdc_local_command = 0;
 	m_curfloppy = NULL;
+	m_in_drq = false;
 }
 
 /*-------------------------------------------------
@@ -142,7 +145,7 @@ UINT8 a2bus_corvfdc02_device::read_c0nx(address_space &space, UINT8 offset)
 
 		case 3: 
 //			printf("Read buffer @ %x = %02x\n", m_bufptr, m_buffer[m_bufptr]);
-			return m_buffer[m_bufptr];
+			return m_buffer[m_bufptr--];
 
 		case 4:	// local status
 			if (m_curfloppy)
@@ -182,7 +185,7 @@ void a2bus_corvfdc02_device::write_c0nx(address_space &space, UINT8 offset, UINT
 			break;
 
 		case 3:	// buffer write
-//			printf("%02x to buffer @ %x\n", data, m_bufptr);
+//			printf("%02x to buffer[%x]\n", data, m_bufptr);
 			m_buffer[m_bufptr--] = data;
 			break;
 
@@ -261,6 +264,21 @@ WRITE_LINE_MEMBER(a2bus_corvfdc02_device::intrq_w)
 
 WRITE_LINE_MEMBER(a2bus_corvfdc02_device::drq_w)
 {
-//	printf("DRQ: %d\n", state);
+	if (state)
+	{
+		// pseudo-DMA direction?
+		if (m_fdc_local_command & 0x40)
+		{
+			m_buffer[m_bufptr] = m_fdc->dma_r(); 
+//			printf("DMA %02x to buffer[%x]\n", m_buffer[m_bufptr], m_bufptr);
+			m_bufptr--;
+			m_bufptr &= 0x1ff;
+		}
+		else
+		{
+			m_fdc->dma_w(m_buffer[m_bufptr++]);
+			m_bufptr &= 0x1ff;
+		}
+	}
 }
 

src/emu/bus/a2bus/corvfdc02.h

@@ -57,6 +57,7 @@ private:
 	UINT16 m_bufptr;
 	UINT8 m_buffer[2048];	// 1x6116 SRAM
 	floppy_image_device *m_curfloppy;
+	bool m_in_drq;
 };
 
 // device type definition

src/lib/formats/concept_dsk.c

@@ -0,0 +1,155 @@
+// license:BSD-3-Clause
+// copyright-holders:Olivier Galibert, R. Belmont
+/*********************************************************************
+
+    formats/concept_dsk.c
+
+    Formats for Corvus Concept
+
+    5.25" DSDD is PC MFM, 77 tracks, double-sided, with 9 sectors per track
+
+*********************************************************************/
+
+#include "emu.h"
+#include "flopimg.h"
+#include "formats/concept_dsk.h"
+
+/* 9 sectors / track, 512 bytes per sector */
+const floppy_image_format_t::desc_e cc525dsdd_format::cc_9_desc[] = {
+	{ MFM, 0x4e, 80 },
+	{ MFM, 0x00, 12 },
+	{ RAW, 0x5224, 3 },
+	{ MFM, 0xfc, 1 },
+	{ MFM, 0x4e, 50 },
+	{ MFM, 0x00, 12 },
+	{ SECTOR_LOOP_START, 1, 9 },
+	{   CRC_CCITT_START, 1 },
+	{     RAW, 0x4489, 3 },
+	{     MFM, 0xfe, 1 },
+	{     TRACK_ID },
+	{     HEAD_ID },
+	{     SECTOR_ID },
+	{     SIZE_ID },
+	{   CRC_END, 1 },
+	{   CRC, 1 },
+	{   MFM, 0x4e, 22 },
+	{   MFM, 0x00, 12 },
+	{   CRC_CCITT_START, 2 },
+	{     RAW, 0x4489, 3 },
+	{     MFM, 0xfb, 1 },
+	{     SECTOR_DATA, -1 },
+	{   CRC_END, 2 },
+	{   CRC, 2 },
+	{   MFM, 0x4e, 84 },
+	{   MFM, 0x00, 12 },
+	{ SECTOR_LOOP_END },
+	{ MFM, 0x4e, 170 },
+	{ END }
+};
+
+cc525dsdd_format::cc525dsdd_format()
+{
+}
+
+const char *cc525dsdd_format::name() const
+{
+	return "img";
+}
+
+const char *cc525dsdd_format::description() const
+{
+	return "Corvus Concept 5.25\" DSDD floppy disk image";
+}
+
+const char *cc525dsdd_format::extensions() const
+{
+	return "img";
+}
+
+bool cc525dsdd_format::supports_save() const
+{
+	return true;
+}
+
+void cc525dsdd_format::find_size(io_generic *io, UINT8 &track_count, UINT8 &head_count, UINT8 &sector_count)
+{
+	UINT64 size = io_generic_size(io);
+
+	track_count = 77;
+	head_count = 2;
+	sector_count = 9;
+
+	UINT32 expected_size = 512 * track_count*head_count*sector_count;
+	if (size == expected_size)
+	{
+		return;
+	}
+
+	track_count = head_count = sector_count = 0;
+}
+
+int cc525dsdd_format::identify(io_generic *io, UINT32 form_factor)
+{
+	UINT8 track_count, head_count, sector_count;
+	find_size(io, track_count, head_count, sector_count);
+
+	if(track_count)
+		return 50;
+	return 0;
+}
+
+bool cc525dsdd_format::load(io_generic *io, UINT32 form_factor, floppy_image *image)
+{
+	UINT8 track_count, head_count, sector_count;
+	find_size(io, track_count, head_count, sector_count);
+
+	UINT8 sectdata[10*512];
+	desc_s sectors[10];
+	for(int i=0; i<sector_count; i++) {
+		sectors[i+1].data = sectdata + 512*i;
+		sectors[i+1].size = 512;
+		sectors[i+1].sector_id = i+1;
+	}
+
+	int track_size = sector_count*512;
+	for(int track=0; track < track_count; track++) {
+		for(int head=0; head < head_count; head++) {
+			io_generic_read(io, sectdata, (track*head_count + head)*track_size, track_size);
+			generate_track(cc_9_desc, track, head, sectors, sector_count, 100000, image);
+		}
+	}
+
+	image->set_variant(floppy_image::DSDD);
+
+	return true;
+}
+
+bool cc525dsdd_format::save(io_generic *io, floppy_image *image)
+{
+	int track_count, head_count, sector_count;
+	get_geometry_mfm_pc(image, 2000, track_count, head_count, sector_count);
+
+	if(track_count != 77)
+		track_count = 77;
+
+	// Happens for a fully unformatted floppy
+	if(!head_count)
+		head_count = 2;
+
+	if(sector_count != 9)
+		sector_count = 9;
+
+	UINT8 sectdata[9*512];
+	int track_size = sector_count*512;
+
+	for(int track=0; track < track_count; track++) {
+		for(int head=0; head < head_count; head++) {
+			get_track_data_mfm_pc(track, head, image, 2000, 512, sector_count, sectdata);
+			io_generic_write(io, sectdata, (track*head_count + head)*track_size, track_size);
+		}
+	}
+
+	return true;
+}
+
+const floppy_format_type FLOPPY_CONCEPT_525DSDD_FORMAT = &floppy_image_format_creator<cc525dsdd_format>;

src/lib/formats/concept_dsk.h

@@ -0,0 +1,36 @@
+/*********************************************************************
+
+    formats/concept_dsk.h
+
+    Formats for Corvus Concept
+
+*********************************************************************/
+
+#ifndef CONCEPT_DSK_H_
+#define CONCEPT_DSK_H_
+
+#include "flopimg.h"
+
+class cc525dsdd_format : public floppy_image_format_t
+{
+public:
+	cc525dsdd_format();
+
+	virtual int identify(io_generic *io, UINT32 form_factor);
+	virtual bool load(io_generic *io, UINT32 form_factor, floppy_image *image);
+	virtual bool save(io_generic *io, floppy_image *image);
+
+	virtual const char *name() const;
+	virtual const char *description() const;
+	virtual const char *extensions() const;
+	virtual bool supports_save() const;
+
+	static const desc_e cc_9_desc[];
+
+private:
+	void find_size(io_generic *io, UINT8 &track_count, UINT8 &head_count, UINT8 &sector_count);
+};
+
+extern const floppy_format_type FLOPPY_CONCEPT_525DSDD_FORMAT;
+
+#endif /* CONCEPT_DSK_H_ */

src/lib/lib.mak

@@ -126,6 +126,7 @@ FORMATSOBJS = \
 	$(LIBOBJ)/formats/coco_cas.o    \
 	$(LIBOBJ)/formats/coco_dsk.o    \
 	$(LIBOBJ)/formats/comx35_dsk.o  \
+	$(LIBOBJ)/formats/concept_dsk.o \
 	$(LIBOBJ)/formats/coupedsk.o    \
 	$(LIBOBJ)/formats/cpis_dsk.o    \
 	$(LIBOBJ)/formats/cqm_dsk.o     \