MEGA65: the start of cartridge support #380

targets/mega65/Makefile

@@ -1,6 +1,6 @@
 ## A work-in-progess MEGA65 (Commodore-65 clone origins) emulator
 ## Part of the Xemu project, please visit: https://github.com/lgblgblgb/xemu
-## Copyright (C)2016-2022 LGB (Gábor Lénárt) <[email protected]>
+## Copyright (C)2016-2023 LGB (Gábor Lénárt) <[email protected]>
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -20,7 +20,7 @@ TARGET		= mega65
 PRG_TARGET	= xmega65
 EMU_DESCRIPTION	= MEGA65
 
-SRCS_TARGET_xmega65	= configdb.c mega65.c sdcard.c uart_monitor.c hypervisor.c m65_snapshot.c memory_mapper.c io_mapper.c vic4.c vic4_palette.c ethernet65.c input_devices.c memcontent.c ui.c fat32.c sdcontent.c audio65.c inject.c dma65.c rom.c hdos.c matrix_mode.c
+SRCS_TARGET_xmega65	= configdb.c mega65.c sdcard.c uart_monitor.c hypervisor.c m65_snapshot.c memory_mapper.c io_mapper.c vic4.c vic4_palette.c ethernet65.c input_devices.c memcontent.c ui.c fat32.c sdcontent.c audio65.c inject.c dma65.c rom.c hdos.c matrix_mode.c cart.c
 SRCS_COMMON_xmega65	= emutools.c cpu65.c cia6526.c emutools_hid.c sid.c f011_core.c c64_kbd_mapping.c emutools_config.c emutools_snapshot.c emutools_files.c emutools_umon.c emutools_socketapi.c ethertap.c d81access.c emutools_gui.c basic_text.c opl3.c lodepng.c
 CFLAGS_TARGET_xmega65	= $(SDL2_CFLAGS) $(MATH_CFLAGS) $(SOCKET_CFLAGS) $(XEMUGUI_CFLAGS)
 LDFLAGS_TARGET_xmega65	= $(SDL2_LIBS) $(MATH_LIBS) $(SOCKET_LIBS) $(XEMUGUI_LIBS)

targets/mega65/cart.c

@@ -0,0 +1,84 @@
+/* A work-in-progess MEGA65 (Commodore 65 clone origins) emulator
+   Part of the Xemu project, please visit: https://github.com/lgblgblgb/xemu
+   Copyright (C)2016-2023 LGB (Gábor Lénárt) <[email protected]>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+#include "xemu/emutools.h"
+#include "cart.h"
+#include "xemu/emutools_files.h"
+
+static Uint8 cart_mem[0x10000];
+static int loaded = 0;
+
+
+void cart_init ( void )
+{
+	memset(cart_mem, 0xFF, sizeof cart_mem);
+}
+
+
+Uint8 cart_read_byte  ( unsigned int addr )
+{
+	Uint8 data = 0xFF;
+	if (addr < sizeof(cart_mem))
+		data = cart_mem[addr];
+	DEBUGPRINT("CART: reading byte ($%02X) at $%X" NL, data, addr + 0x4000000);
+	return data;
+}
+
+
+void cart_write_byte ( unsigned int addr, Uint8 data )
+{
+	DEBUGPRINT("CART: writing byte ($%02X) at $%X" NL, data, addr + 0x4000000);
+}
+
+
+int cart_load_bin ( const char *fn, const unsigned int addr, const char *cry )
+{
+	if (!fn || !*fn)
+		return 0;
+	loaded = 0;
+	if (addr >= sizeof(cart_mem)) {
+		if (cry)
+			ERROR_WINDOW("%s\nOutside of 64K range\n%s", cry, fn);
+		return -1;
+	}
+	const int ret = xemu_load_file(fn, cart_mem + addr, 1, sizeof(cart_mem) - addr, cry);
+	if (ret <= 0)
+		return -1;
+	DEBUGPRINT("CART: %d byte(s) loaded at offset $%04X from file %s" NL, ret, addr, fn);
+	loaded = 1;
+	return 0;
+}
+
+
+int cart_detect_id ( void )
+{
+	static const Uint8 cart_id[] = {'M', '6', '5'};
+	return memcmp(cart_mem + 0x8007, cart_id, sizeof cart_id);
+}
+
+
+int cart_is_loaded ( void )
+{
+	return loaded;
+}
+
+
+void cart_copy_from ( const Uint16 cart_addr, Uint8 *target, const Uint16 size )
+{
+	memcpy(target, cart_mem + cart_addr, size);
+}

targets/mega65/cart.h

@@ -0,0 +1,30 @@
+/* A work-in-progess MEGA65 (Commodore 65 clone origins) emulator
+   Part of the Xemu project, please visit: https://github.com/lgblgblgb/xemu
+   Copyright (C)2016-2023 LGB (Gábor Lénárt) <[email protected]>
+
+This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
+
+#ifndef XEMU_MEGA65_CART_H_INCLUDED
+#define XEMU_MEGA65_CART_H_INCLUDED
+
+extern void  cart_init       ( void );
+extern Uint8 cart_read_byte  ( unsigned int addr );
+extern void  cart_write_byte ( unsigned int addr, Uint8 data );
+extern int   cart_load_bin   ( const char *fn, const unsigned int addr, const char *cry );
+extern void  cart_copy_from  ( const Uint16 cart_addr, Uint8 *target, const Uint16 size );
+extern int   cart_detect_id  ( void );
+extern int   cart_is_loaded  ( void );
+
+#endif

targets/mega65/configdb.c

@@ -75,6 +75,7 @@ static const struct xemutools_configdef_str_st str_options[] = {
 #endif
 	{ "gui",	NULL, "Select GUI type for usage. Specify some insane str to get a list", &configdb.selectedgui },
 	{ "importbas",	NULL, "Import and RUN BASIC65 program from TEXT file", &configdb.importbas },
+	{ "cartbin8000",NULL, "Load binary cartridge image from $8000", &configdb.cartbin8000 },
 	{ NULL }
 };
 
@@ -151,6 +152,7 @@ static const void *do_not_save_opts[] = {
 	&emu_is_sleepless, &emu_is_headless, &configdb.testing,
 	&configdb.dumpmem, &configdb.dumpscreen, &configdb.screenshot_and_exit,
 	&configdb.testing, &configdb.hyperdebug, &configdb.hyperdebugfreezer, &configdb.usestubrom, &configdb.useinitrom, &configdb.useutilmenu,
+	&configdb.cartbin8000,
 	NULL
 };
 

targets/mega65/configdb.h

@@ -97,6 +97,7 @@ struct configdb_st {
 	// $60/$61/$62 = qmtecha100t/qmtecha200t/qmtecha325t, $21/$22=megaphoner1/megaphoner4
 	int	mega65_model;
 	int	colour_effect;
+	char	*cartbin8000;
 	int	hicked;
 	int	prgmode;
 	int	rtc_hour_offset;

targets/mega65/mega65.c

@@ -42,6 +42,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
 #include "configdb.h"
 #include "xemu/emutools_socketapi.h"
 #include "rom.h"
+#include "cart.h"
 
 // "Typical" size in default settings (video standard is PAL, default border settings).
 // See also vic4.h
@@ -355,6 +356,7 @@ static void mega65_init ( void )
 	} while (0);
 	// *** Initializes memory subsystem of MEGA65 emulation itself
 	memory_init();
+	cart_load_bin(configdb.cartbin8000, 0x8000, "Cannot load binary cartridge image from $8000");
 	// Load contents of NVRAM.
 	// Also store as "nvram_original" so we can sense on shutdown of the emu, if we need to up-date the on-disk version
 	// If we fail to load it (does not exist?) it will be written out anyway on exit.

targets/mega65/memory_mapper.c

@@ -35,6 +35,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
 #include "ethernet65.h"
 #include "audio65.h"
 #include "sdcard.h"
+#include "cart.h"
 #include <string.h>
 
 #define ALLOW_CPU_CUSTOM_FUNCTIONS_INCLUDE
@@ -338,6 +339,14 @@ DEFINE_WRITER(i2c_io_writer) {
 			break;
 	}
 }
+// "Slow device" ~ cardridge space
+DEFINE_READER(slowdev_reader) {
+	return cart_read_byte(GET_READER_OFFSET());
+}
+DEFINE_WRITER(slowdev_writer) {
+	cart_write_byte(GET_WRITER_OFFSET(), data);
+}
+
 // Not implemented yet, just here, since freezer accesses this memory area, and without **some** dummy
 // support, it would cause "unhandled memory access" warning in Xemu.
 DEFINE_READER(mem1541_reader) {
@@ -372,7 +381,7 @@ static const struct m65_memory_map_st m65_memory_map[] = {
 	{ 0xFFD7000, 0xFFD7FFF, i2c_io_reader, i2c_io_writer },			// I2C devices
 	{ 0x8000000, 0x8000000 + SLOW_RAM_SIZE - 1, slow_ram_reader, slow_ram_writer },		// "slow RAM" also called "hyper RAM" (not to be confused with hypervisor RAM!)
 	{ 0x8000000 + SLOW_RAM_SIZE, 0xFDFFFFF, dummy_reader, dummy_writer },			// ununsed big part of the "slow RAM" or so ...
-	{ 0x4000000, 0x7FFFFFF, dummy_reader, dummy_writer },		// slow RAM memory area, not exactly known what it's for, let's define as "dummy"
+	{ 0x4000000, 0x7FFFFFF, slowdev_reader, slowdev_writer },		// slow RAM memory area ~ cartridge
 	{ 0xFE00000, 0xFE000FF, opl3_reader, opl3_writer },
 	{ 0x60000, 0xFFFFF, dummy_reader, dummy_writer },			// upper "unused" area of C65 (!) memory map. It seems C65 ROMs want it (Expansion RAM?) so we define as unused.
 	{ 0xFFDB000, 0xFFDFFFF, mem1541_reader, mem1541_writer },		// 1541's 16K ROM + 4K RAM, not so much used currently, but freezer seems to access it, for example ...
@@ -498,6 +507,7 @@ void memory_init ( void )
 	memset(D6XX_registers, 0, sizeof D6XX_registers);
 	memset(D7XX, 0xFF, sizeof D7XX);
 	memset(i2c_regs, 0, sizeof i2c_regs);
+	cart_init();
 	rom_protect = 0;
 	in_hypervisor = 0;
 	for (a = 0; a < MEM_SLOTS; a++) {

targets/mega65/ui.c

@@ -40,6 +40,7 @@ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
 #include "hypervisor.h"
 #include "xemu/cpu65.h"
 #include "xemu/emutools_config.h"
+#include "cart.h"
 
 
 // Used by UI CBs to maintain configDB persistence
@@ -653,10 +654,46 @@ static void ui_cb_colour_effect ( const struct menu_st *m, int *query )
 	vic4_set_emulation_colour_effect(VOIDPTR_TO_INT(m->user_data));
 }
 
+static void ui_cb_load_bin_cart ( const struct menu_st *m, int *query )
+{
+	char fnbuf[PATH_MAX + 1];
+	static char dir[PATH_MAX + 1] = "";
+	_check_file_selection_default_override(dir);
+	if (!xemugui_file_selector(
+		XEMUGUI_FSEL_OPEN | XEMUGUI_FSEL_FLAG_STORE_DIR,
+		"Select binary cartridge",
+		dir,
+		fnbuf,
+		sizeof fnbuf
+	)) {
+		if (!cart_load_bin(fnbuf, VOIDPTR_TO_INT(m->user_data), "Cannot load binary cartridge"))
+			xemucfg_set_str(&configdb.cartbin8000, fnbuf);
+	} else
+		DEBUGPRINT("UI: file selection for PRG injection was cancelled." NL);
+}
+
+static void ui_start_cartridge ( void )
+{
+	if (!cart_is_loaded()) {
+		ERROR_WINDOW("No cartridge is loaded yet.");
+		return;
+	}
+	if (cart_detect_id()) {
+		INFO_WINDOW("Cartridge signature M65 not detected. Start with your own risk.");
+	}
+	cart_copy_from(0x8000, main_ram + 0x8000, 0x2000);
+	INFO_WINDOW("Copied. Type BANK0:SYS$8000 to start");
+}
+
 
 /**** MENU SYSTEM ****/
 
 
+static const struct menu_st menu_cartridge[] = {
+	{ "Load BIN cartridge to $8000",XEMUGUI_MENUID_CALLABLE,	ui_cb_load_bin_cart, (void*)0x8000 },
+	{ "Start cartridge",		XEMUGUI_MENUID_CALLABLE,	xemugui_cb_call_user_data, ui_start_cartridge },
+	{ NULL }
+};
 static const struct menu_st menu_colour_effects[] = {
 	{ "Normal colours",		XEMUGUI_MENUID_CALLABLE | XEMUGUI_MENUFLAG_QUERYBACK,	ui_cb_colour_effect, (void*)0 },
 	{ "Grayscale",			XEMUGUI_MENUID_CALLABLE | XEMUGUI_MENUFLAG_QUERYBACK,	ui_cb_colour_effect, (void*)1 },
@@ -857,6 +894,7 @@ static const struct menu_st menu_disks[] = {
 	{ "Drive-8",			XEMUGUI_MENUID_SUBMENU,		NULL, menu_drv8    },
 	{ "Drive-9",			XEMUGUI_MENUID_SUBMENU,		NULL, menu_drv9    },
 	{ "SD-card",			XEMUGUI_MENUID_SUBMENU,		NULL, menu_sdcard  },
+	{ "Cartridge",			XEMUGUI_MENUID_SUBMENU,		NULL, menu_cartridge },
 	{ NULL }
 };
 static const struct menu_st menu_audio_stereo[] = {
@@ -942,7 +980,7 @@ static const struct menu_st menu_main[] = {
 	{ "Display",			XEMUGUI_MENUID_SUBMENU,		NULL, menu_display	},
 	{ "Input devices",		XEMUGUI_MENUID_SUBMENU,		NULL, menu_inputdevices	},
 	{ "Audio",			XEMUGUI_MENUID_SUBMENU,		NULL, menu_audio	},
-	{ "Disks",			XEMUGUI_MENUID_SUBMENU,		NULL, menu_disks	},
+	{ "Disks / Cart",		XEMUGUI_MENUID_SUBMENU,		NULL, menu_disks	},
 	{ "Reset / ROM switching",	XEMUGUI_MENUID_SUBMENU,		NULL, menu_reset	},
 	{ "Debug / Advanced",		XEMUGUI_MENUID_SUBMENU,		NULL, menu_debug	},
 	{ "Configuration",		XEMUGUI_MENUID_SUBMENU,		NULL, menu_config	},