coco3: Make banked cartridges actually work

hash/coco_cart.xml

@@ -937,6 +937,7 @@ Compiled by K1W1 and Cowering (from GoodCoCo)
 		<info name="developer" value="Epyx" />
 		<info name="serial" value="26-3100" />
 		<part name="cart" interface="coco_cart">
+			<feature name="slot" value="banked_16k" />
 			<dataarea name="rom" size="32768">
 				<rom name="mind-roll (1988)(26-3100)(epyx)[!].rom" size="32768" crc="83bd6056" sha1="f7b505383ca5739a98a5130549d534c38cb1bd2f" offset="0" />
 			</dataarea>
@@ -1076,6 +1077,7 @@ Compiled by K1W1 and Cowering (from GoodCoCo)
 		<info name="developer" value="Activision" />
 		<info name="serial" value="26-3165" />
 		<part name="cart" interface="coco_cart">
+			<feature name="slot" value="banked_16k" />
 			<dataarea name="rom" size="65536">
 				<rom name="predator (1989) (26-3165) (activision).rom" size="65536" crc="a9680ede" sha1="551d8d95fd310b2d72b1e22028a517c325fe9ab4" offset="0" />
 			</dataarea>
@@ -1160,6 +1162,7 @@ Compiled by K1W1 and Cowering (from GoodCoCo)
 		<info name="serial" value="26-3164" />
 		<sharedfeat name="compatibility" value="COCO3" />
 		<part name="cart" interface="coco_cart">
+			<feature name="slot" value="banked_16k" />
 			<dataarea name="rom" size="131072">
 				<rom name="robocop (1988)(26-3164)(data east).rom" size="131072" crc="dd94dd06" sha1="82ad8a207a446d99455926bd27d4490578de2b41" offset="0" />
 			</dataarea>

src/devices/bus/coco/coco_pak.cpp

@@ -24,6 +24,11 @@ ROM_START( coco_pak )
 	// this region is filled by cococart_slot_device::call_load()
 ROM_END
 
+ROM_START( coco_pak_banked )
+	ROM_REGION(0x20000, CARTSLOT_TAG, ROMREGION_ERASE00)
+	// this region is filled by cococart_slot_device::call_load()
+ROM_END
+
 
 //-------------------------------------------------
 //  INPUT_PORTS( coco_cart_autostart )
@@ -136,6 +141,7 @@ DEFINE_DEVICE_TYPE(COCO_PAK_BANKED, coco_pak_banked_device, "cocopak_banked", "C
 
 coco_pak_banked_device::coco_pak_banked_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock)
 	: coco_pak_device(mconfig, type, tag, owner, clock)
+	, m_pos(0)
 {
 }
 coco_pak_banked_device::coco_pak_banked_device(const machine_config &mconfig, const char *tag, device_t *owner, uint32_t clock)
@@ -143,39 +149,58 @@ coco_pak_banked_device::coco_pak_banked_device(const machine_config &mconfig, co
 {
 }
 
-/*-------------------------------------------------
+//-------------------------------------------------
-    device_reset - device-specific startup
+//  rom_region - device-specific ROM region
--------------------------------------------------*/
+//-------------------------------------------------
+
+const tiny_rom_entry *coco_pak_banked_device::device_rom_region() const
+{
+	return ROM_NAME( coco_pak_banked );
+}
+
+//-------------------------------------------------
+//  device_start - device-specific startup
+//-------------------------------------------------
+
+void coco_pak_banked_device::device_start()
+{
+	coco_pak_device::device_start();
+
+	save_item(NAME(m_pos));
+}
+
+//-------------------------------------------------
+//  device_reset - device-specific startup
+//-------------------------------------------------
 
 void coco_pak_banked_device::device_reset()
 {
 	coco_pak_device::device_reset();
 
-	banked_pak_set_bank(0);
+	m_pos = 0;
+	cart_base_changed();
 }
 
-/*-------------------------------------------------
+//-------------------------------------------------
-    banked_pak_set_bank - function to set the bank
+//  get_cart_base
--------------------------------------------------*/
+//-------------------------------------------------
 
-void coco_pak_banked_device::banked_pak_set_bank(uint32_t bank)
+uint8_t *coco_pak_banked_device::get_cart_base()
 {
-	uint64_t pos;
-	uint32_t i;
 	uint8_t *rom = memregion(CARTSLOT_TAG)->base();
 	uint32_t rom_length = memregion(CARTSLOT_TAG)->bytes();
 
-	if (m_cart->exists()) {
+	return &rom[(m_pos * 0x4000) % rom_length];
-		pos = (bank * 0x4000) % m_cart->length();
-
-		for (i = 0; i < rom_length / 0x4000; i++)
-		{
-			m_cart->fseek(pos, SEEK_SET);
-			m_cart->fread(&rom[i * 0x4000], 0x4000);
-		}
-	}
 }
 
+//-------------------------------------------------
+//  get_cart_size
+//-------------------------------------------------
+
+uint32_t coco_pak_banked_device::get_cart_size()
+{
+	return 0x4000;
+}
 
 //-------------------------------------------------
 //  scs_write
@@ -187,7 +212,11 @@ WRITE8_MEMBER(coco_pak_banked_device::scs_write)
 	{
 		case 0:
 			// set the bank
-			banked_pak_set_bank(data);
+			if (m_pos != data)
+			{
+				m_pos = data;
+				cart_base_changed();
+			}
 			break;
 	}
 }

src/devices/bus/coco/coco_pak.h

@@ -53,11 +53,15 @@ protected:
 	coco_pak_banked_device(const machine_config &mconfig, device_type type, const char *tag, device_t *owner, uint32_t clock);
 
 	// device-level overrides
+	virtual const tiny_rom_entry *device_rom_region() const override;
+	virtual void device_start() override;
 	virtual void device_reset() override;
+	virtual uint8_t *get_cart_base() override;
+	virtual uint32_t get_cart_size() override;
 	virtual DECLARE_WRITE8_MEMBER(scs_write) override;
 
 private:
-	void banked_pak_set_bank(uint32_t bank);
+	uint8_t m_pos;
 };
 
 #endif // MAME_BUS_COCO_COCO_PAK_H

src/devices/bus/coco/cococart.cpp

@@ -379,6 +379,18 @@ uint8_t* cococart_slot_device::get_cart_base()
 }
 
 
+//-------------------------------------------------
+//  get_cart_size
+//-------------------------------------------------
+
+uint32_t cococart_slot_device::get_cart_size()
+{
+	if (m_cart != nullptr)
+		return m_cart->get_cart_size();
+	return 0;
+}
+
+
 //-------------------------------------------------
 //  set_cart_base_update
 //-------------------------------------------------
@@ -401,16 +413,16 @@ image_init_result cococart_slot_device::call_load()
 		offs_t read_length;
 		if (!loaded_through_softlist())
 		{
-			read_length = fread(m_cart->get_cart_base(), 0x8000);
+			read_length = fread(m_cart->get_cart_base(), m_cart->get_cart_size());
 		}
 		else
 		{
 			read_length = get_software_region_length("rom");
 			memcpy(m_cart->get_cart_base(), get_software_region("rom"), read_length);
 		}
-		while(read_length < 0x8000)
+		while(read_length < m_cart->get_cart_size())
 		{
-			offs_t len = std::min(read_length, 0x8000 - read_length);
+			offs_t len = std::min(read_length, m_cart->get_cart_size() - read_length);
 			memcpy(m_cart->get_cart_base() + read_length, m_cart->get_cart_base(), len);
 			read_length += len;
 		}
@@ -522,6 +534,16 @@ uint8_t* device_cococart_interface::get_cart_base()
 }
 
 
+//-------------------------------------------------
+//  get_cart_size
+//-------------------------------------------------
+
+uint32_t device_cococart_interface::get_cart_size()
+{
+	return 0x8000;
+}
+
+
 //-------------------------------------------------
 //  set_cart_base_update
 //-------------------------------------------------

src/devices/bus/coco/cococart.h

@@ -119,7 +119,8 @@ public:
 	void twiddle_q_lines();
 
 	// cart base
-	uint8_t* get_cart_base();
+	uint8_t *get_cart_base();
+	uint32_t get_cart_size();
 	void set_cart_base_update(cococart_base_update_delegate update);
 
 private:
@@ -184,6 +185,7 @@ public:
 	virtual void set_sound_enable(bool sound_enable);
 
 	virtual uint8_t* get_cart_base();
+	virtual uint32_t get_cart_size();
 	void set_cart_base_update(cococart_base_update_delegate update);
 
 	virtual void interface_config_complete() override;

src/mame/video/gime.cpp

@@ -173,6 +173,7 @@ void gime_device::device_start(void)
 	// set up ROM/RAM pointers
 	m_rom = machine().root_device().memregion(m_maincpu_tag)->base();
 	m_cart_rom = m_cart_device->get_cart_base();
+	m_cart_size = m_cart_device->get_cart_size();
 
 	// populate palettes
 	m_composite_phase_invert = false;
@@ -348,6 +349,7 @@ void gime_device::device_pre_save()
 void gime_device::device_post_load()
 {
 	super::device_post_load();
+	update_cart_rom();
 	update_memory();
 	update_cpu_clock();
 
@@ -566,11 +568,15 @@ void gime_device::update_memory(int bank)
 		block = rom_map[m_gime_registers[0] & 3][(block & 0x3F) - 0x3C];
 
 		// are we in onboard ROM or cart ROM?
-		uint8_t *rom_ptr = (block & 4) ? m_cart_rom : m_rom;
+		if (BIT(block, 2) && m_cart_rom != nullptr)
-		// TODO: make this unmapped
+		{
-		if (rom_ptr==nullptr) rom_ptr = m_rom;
+			// perform the look up
-		// perform the look up
+			memory = &m_cart_rom[((block & 3) * 0x2000) % m_cart_size];
-		memory = &rom_ptr[(block & 3) * 0x2000];
+		}
+		else
+		{
+			memory = &m_rom[(block & 3) * 0x2000];
+		}
 		is_read_only = true;
 	}
 	else
@@ -608,6 +614,7 @@ uint8_t *gime_device::memory_pointer(uint32_t address)
 void gime_device::update_cart_rom(void)
 {
 	m_cart_rom = m_cart_device->get_cart_base();
+	m_cart_size = m_cart_device->get_cart_size();
 	update_memory();
 }
 

src/mame/video/gime.h

@@ -196,12 +196,13 @@ private:
 	cococart_slot_device *      m_cart_device;
 	memory_bank *               m_read_banks[9];
 	memory_bank *               m_write_banks[9];
-	uint8_t *                     m_rom;
+	uint8_t *                   m_rom;
-	uint8_t *                     m_cart_rom;
+	uint8_t *                   m_cart_rom;
+	uint32_t                    m_cart_size;
 	pixel_t                     m_composite_palette[64];
 	pixel_t                     m_composite_bw_palette[64];
 	pixel_t                     m_rgb_palette[64];
-	uint8_t                       m_dummy_bank[0x2000];
+	uint8_t                     m_dummy_bank[0x2000];
 
 	const char *m_maincpu_tag;  /* tag of main CPU */
 	const char *m_ram_tag;      /* tag of RAM device */