diff --git a/src/mame/drivers/dkmb.cpp b/src/mame/drivers/dkmb.cpp
index 53d42cca80d..6534feed830 100644
--- a/src/mame/drivers/dkmb.cpp
+++ b/src/mame/drivers/dkmb.cpp
@@ -1,5 +1,5 @@
 // license:BSD-3-Clause
-// copyright-holders:
+// copyright-holders:David Haywood
 
 /*
 Donkey Kong / Donkey Kong Jr / Mario Bros
@@ -36,16 +36,21 @@ class dkmb_state : public driver_device
 public:
 	dkmb_state(const machine_config &mconfig, device_type type, const char *tag)
 		: driver_device(mconfig, type, tag),
-		m_maincpu(*this, "maincpu")
+		m_maincpu(*this, "maincpu"),
+		m_framebuffer(*this, "framebuffer")
 	{ }
 
 	void dkmb(machine_config &config);
 
+	DECLARE_READ64_MEMBER(unk_2060000_r);
+	DECLARE_READ64_MEMBER(unk_20c0010_r);
+
 protected:
 	virtual void machine_start() override;
 
 private:
 	required_device<cpu_device> m_maincpu;
+	required_shared_ptr<uint64_t> m_framebuffer;
 
 	uint32_t screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect);
 
@@ -59,12 +64,53 @@ void dkmb_state::machine_start()
 
 uint32_t dkmb_state::screen_update(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect)
 {
+	int count = 0;
+	for (int y = 0; y < 256; y++)
+	{
+		uint32_t* dst = &bitmap.pix32(y);
+
+		for (int x = 0; x < 1024 / 2; x++)
+		{
+			uint64_t val = m_framebuffer[count];
+
+			dst[(x * 2) + 0] = (val >> 32) & 0x00ffffff;
+			dst[(x * 2) + 1] = (val >> 0)  & 0x00ffffff;
+
+			count++;
+		}
+	}
+
 	return 0;
 }
 
+
+READ64_MEMBER(dkmb_state::unk_2060000_r)
+{
+	return ((u64)machine().rand()) << 56;
+}
+
+READ64_MEMBER(dkmb_state::unk_20c0010_r)
+{
+	return ((u64)machine().rand()) << 56;
+}
+
 void dkmb_state::main_map(address_map &map)
 {
-	map(0x00ff0000, 0x00ffffff).ram();
+	map(0x00000000, 0x000fffff).ram(); // copies code to RAM and runs it from here
+	map(0x00100000, 0x001fffff).ram().share("framebuffer"); // seems to be a 1024x256 ARGB bitmap, with 320 entries used for each line and 224 lines, so framebuffer? (but then gets overwritten with data not of that format?)
+
+	map(0x00e00000, 0x00ffffff).ram(); // size uncertain
+
+	map(0x02080000, 0x02080007).ram(); // write
+	map(0x02060000, 0x02060007).r(FUNC(dkmb_state::unk_2060000_r)); // read
+	map(0x020c0000, 0x020c0007).ram(); // write
+	map(0x020c0010, 0x020c0017).r(FUNC(dkmb_state::unk_20c0010_r)); // read
+
+    map(0x04090000, 0x0409ffff).ram(); // size uncertain
+
+	// map(0xff000000, 0xff0fffff) // looks like flash ROM access, mirror of main ROM or just checking if extra exist?
+	// map(0xff800000, 0xff8fffff) // looks like flash ROM access, mirror of main ROM or just checking if extra exist?
+
 	map(0xffe00000, 0xffffffff).rom().region("maincpu", 0);
 }
 
@@ -83,8 +129,8 @@ MACHINE_CONFIG_START(dkmb_state::dkmb)
 	MCFG_SCREEN_ADD("screen", RASTER)  // wrong
 	MCFG_SCREEN_REFRESH_RATE(60)
 	MCFG_SCREEN_UPDATE_DRIVER(dkmb_state, screen_update)
-	MCFG_SCREEN_SIZE(640, 480)
-	MCFG_SCREEN_VISIBLE_AREA(0, 256, 0, 240)
+	MCFG_SCREEN_SIZE(1024, 256)
+	MCFG_SCREEN_VISIBLE_AREA(0, 1024-1, 0, 256-1)
 
 	MCFG_PALETTE_ADD("palette", 65536)
 
@@ -95,10 +141,18 @@ MACHINE_CONFIG_END
 
 ROM_START( dkmb )
 	ROM_REGION64_BE(0x200000, "maincpu", 0)
-	ROM_LOAD("donkeykong.u14", 0x00000, 0x200000, CRC(7895fe2d) SHA1(134174c02ce3c5d28a890ca57dc36677873b1dc8) )
+	ROM_LOAD("donkeykong.u14", 0x00000, 0x200000, CRC(7895fe2d) SHA1(134174c02ce3c5d28a890ca57dc36677873b1dc8) ) // what type of ROM is this?
 
 	ROM_REGION( 0x1000, "pic", 0 )
-	ROM_LOAD("12c508.u12", 0x000, 0x09db, CRC(3adb3e33) SHA1(36a96886d83b64633eea83e57bdfa8a20c6d4f6a) )
+	/*
+		Intel HEX format dump.  When converted to binary using
+		"srec_cat.exe 12c508.u12 -intel -o 12c508.bin -binary"
+		this contains only the string
+		"Copyright 2001 Core Technologies why are you looking in here?"
+		in the first 0x80 bytes, which is the unprotected area of the PIC.
+		the rest is blank, therefore protected and a bad dump
+	*/
+	ROM_LOAD("12c508.u12", 0x000, 0x09db, BAD_DUMP CRC(3adb3e33) SHA1(36a96886d83b64633eea83e57bdfa8a20c6d4f6a) )
 ROM_END
 
 GAME( 2003, dkmb, 0, dkmb, dkmb, dkmb_state, empty_init, ROT270, "Namco / Nintendo / Cosmodog", "Donkey Kong / Donkey Kong Jr / Mario Bros", MACHINE_IS_SKELETON )