From c41d2e4e1cc52036a757facab198d49ed371ca02 Mon Sep 17 00:00:00 2001
From: Wilbert Pol <wilbert@jdg.info>
Date: Sat, 4 May 2013 18:34:31 +0000
Subject: [PATCH] (MESS) electron.c: Added cartridge support.  [Wilbert Pol]

---
 src/mess/drivers/electron.c  | 13 ++++++++-
 src/mess/includes/electron.h |  1 +
 src/mess/machine/electron.c  | 51 ++++++++++++++++++++++++++++++++++++
 3 files changed, 64 insertions(+), 1 deletion(-)

diff --git a/src/mess/drivers/electron.c b/src/mess/drivers/electron.c
index 87d34b9031d..1b9f52bd620 100644
--- a/src/mess/drivers/electron.c
+++ b/src/mess/drivers/electron.c
@@ -13,9 +13,11 @@ Incomplete:
     - Graphics (seems to be wrong for several games)
     - 1 MHz bus is not emulated
     - Bus claiming by ULA is not implemented
+    - Currently the cartridge support always loads the upper rom in page 12
+      and the lower rom in page 0. This might need further documentation in
+      the software list and loading code.
 
 Missing:
-    - Support for ROM images
     - Support for floppy disks
     - Other peripherals
     - Keyboard is missing the 'Break' key
@@ -26,6 +28,7 @@ Missing:
 #include "cpu/m6502/m6502.h"
 #include "includes/electron.h"
 #include "imagedev/cassette.h"
+#include "imagedev/cartslot.h"
 #include "formats/uef_cas.h"
 #include "sound/beep.h"
 
@@ -196,6 +199,14 @@ static MACHINE_CONFIG_START( electron, electron_state )
 	MCFG_SOUND_ROUTE( ALL_OUTPUTS, "mono", 1.00 )
 
 	MCFG_CASSETTE_ADD( "cassette", electron_cassette_interface )
+
+	MCFG_CARTSLOT_ADD("cart")
+	MCFG_CARTSLOT_EXTENSION_LIST("bin")
+	MCFG_CARTSLOT_NOT_MANDATORY
+	MCFG_CARTSLOT_LOAD(electron_state, electron_cart)
+	MCFG_CARTSLOT_INTERFACE("electron_cart")
+	/* software lists */
+	MCFG_SOFTWARE_LIST_ADD("cart_list","electron_cart")
 MACHINE_CONFIG_END
 
 
diff --git a/src/mess/includes/electron.h b/src/mess/includes/electron.h
index 2fbdb5acea9..52c1249397f 100644
--- a/src/mess/includes/electron.h
+++ b/src/mess/includes/electron.h
@@ -90,6 +90,7 @@ public:
 	inline UINT8 read_vram( UINT16 addr );
 	inline void electron_plot_pixel(bitmap_ind16 &bitmap, int x, int y, UINT32 color);
 	void electron_interrupt_handler(int mode, int interrupt);
+	DECLARE_DEVICE_IMAGE_LOAD_MEMBER( electron_cart );
 };
 
 
diff --git a/src/mess/machine/electron.c b/src/mess/machine/electron.c
index f2884fa78ed..f27a14ece4d 100644
--- a/src/mess/machine/electron.c
+++ b/src/mess/machine/electron.c
@@ -338,3 +338,54 @@ void electron_state::machine_start()
 	machine().scheduler().timer_set(attotime::zero, timer_expired_delegate(FUNC(electron_state::setup_beep),this));
 	m_tape_timer = machine().scheduler().timer_alloc(timer_expired_delegate(FUNC(electron_state::electron_tape_timer_handler),this));
 }
+
+DEVICE_IMAGE_LOAD_MEMBER( electron_state, electron_cart )
+{
+	UINT8 *user1 = memregion("user1")->base() + 0x4000;
+
+	if (image.software_entry() == NULL)
+	{
+		UINT32 filesize = image.length();
+
+		if ( filesize != 16384 )
+		{
+			image.seterror(IMAGE_ERROR_UNSPECIFIED, "Invalid size. Only size 16384 is supported");
+			return IMAGE_INIT_FAIL;
+		}
+
+		if (image.fread( user1 + 12 * 16384, filesize) != filesize)
+		{
+			image.seterror(IMAGE_ERROR_UNSPECIFIED, "Error loading file");
+			return IMAGE_INIT_FAIL;
+		}
+
+		return IMAGE_INIT_PASS;
+	}
+
+	int upsize = image.get_software_region_length("uprom");
+	int losize = image.get_software_region_length("lorom");
+
+	if ( upsize != 16384 && upsize != 0 )
+	{
+		image.seterror(IMAGE_ERROR_UNSPECIFIED, "Invalid size for uprom");
+		return IMAGE_INIT_FAIL;
+	}
+
+	if ( losize != 16384 && losize != 0 )
+	{
+		image.seterror(IMAGE_ERROR_UNSPECIFIED, "Invalid size for lorom");
+		return IMAGE_INIT_FAIL;
+	}
+
+	if ( upsize )
+	{
+		memcpy( user1 + 12 * 16384, image.get_software_region("uprom"), upsize );
+	}
+
+	if ( losize )
+	{
+		memcpy( user1 + 0 * 16384, image.get_software_region("lorom"), losize );
+	}
+
+	return IMAGE_INIT_PASS;
+}