diff --git a/src/mame/drivers/cischeat.cpp b/src/mame/drivers/cischeat.cpp
index aa276fa8806..493973b97c0 100644
--- a/src/mame/drivers/cischeat.cpp
+++ b/src/mame/drivers/cischeat.cpp
@@ -893,7 +893,7 @@ void captflag_state::oki2_map(address_map &map)
 void cischeat_state::bigrun_map2(address_map &map)
 {
 	map(0x000000, 0x03ffff).rom();                                                 // ROM
-	map(0x040000, 0x047fff).ram().share("share1");                              // Shared RAM (with Main CPU)
+	map(0x040000, 0x043fff).ram().share("share1");                              // Shared RAM (with Main CPU)
 	map(0x080000, 0x0807ff).ram().share("roadram.0");   // Road RAM
 	map(0x0c0000, 0x0c3fff).ram();                                                 // RAM
 }
@@ -901,7 +901,7 @@ void cischeat_state::bigrun_map2(address_map &map)
 void cischeat_state::bigrun_map3(address_map &map)
 {
 	map(0x000000, 0x03ffff).rom();                                                 // ROM
-	map(0x040000, 0x047fff).ram().share("share2");                              // Shared RAM (with Main CPU)
+	map(0x040000, 0x043fff).ram().share("share2");                              // Shared RAM (with Main CPU)
 	map(0x080000, 0x0807ff).ram().share("roadram.1");   // Road RAM
 	map(0x0c0000, 0x0c3fff).ram();                                                 // RAM
 }
@@ -940,7 +940,7 @@ void cischeat_state::cischeat_map3(address_map &map)
 void cischeat_state::f1gpstar_map2(address_map &map)
 {
 	map(0x000000, 0x03ffff).rom();                                                 // ROM
-	map(0x080000, 0x0807ff).ram().share("share1");                              // Shared RAM (with Main CPU)
+	map(0x080000, 0x087fff).ram().share("share1");                              // Shared RAM (with Main CPU)
 	map(0x100000, 0x1007ff).ram().share("roadram.0");   // Road RAM
 	map(0x180000, 0x183fff).ram();                                                 // RAM
 	map(0x200000, 0x200001).nopw();                                            // watchdog
@@ -949,7 +949,7 @@ void cischeat_state::f1gpstar_map2(address_map &map)
 void cischeat_state::f1gpstar_map3(address_map &map)
 {
 	map(0x000000, 0x03ffff).rom();                                                 // ROM
-	map(0x080000, 0x0807ff).ram().share("share2");                              // Shared RAM (with Main CPU)
+	map(0x080000, 0x087fff).ram().share("share2");                              // Shared RAM (with Main CPU)
 	map(0x100000, 0x1007ff).ram().share("roadram.1");   // Road RAM
 	map(0x180000, 0x183fff).ram();                                                 // RAM
 	map(0x200000, 0x200001).nopw();                                            // watchdog
diff --git a/src/mame/drivers/cps3.cpp b/src/mame/drivers/cps3.cpp
index ab0408d1a1c..a73d17699e3 100644
--- a/src/mame/drivers/cps3.cpp
+++ b/src/mame/drivers/cps3.cpp
@@ -2139,7 +2139,7 @@ void cps3_state::cps3_map(address_map &map)
 	map(0x03000000, 0x030003ff).ram(); // 'FRAM' (sfiii and warzard memory test mode ONLY, and only odd bytes)
 
 	map(0x04000000, 0x0407ffff).ram().share("spriteram"); // Sprite RAM
-	map(0x04080000, 0x040bffff).rw(FUNC(cps3_state::colourram_r), FUNC(cps3_state::colourram_w)).share("colourram");  // Colour RAM 0x20000 colours
+	map(0x04080000, 0x040bffff).rw(FUNC(cps3_state::colourram_r), FUNC(cps3_state::colourram_w));  // Colour RAM 0x20000 colours
 	// PPU registers
 	map(0x040c0000, 0x040c0007).nopr(); // ?? warzard reads this but not use values, dev/debug leftovers ?
 	map(0x040c000c, 0x040c000d).r(FUNC(cps3_state::dma_status_r));
diff --git a/src/mame/drivers/crvision.cpp b/src/mame/drivers/crvision.cpp
index ef0177bb6e7..0a9a8fb977a 100644
--- a/src/mame/drivers/crvision.cpp
+++ b/src/mame/drivers/crvision.cpp
@@ -164,8 +164,8 @@ void crvision_state::crvision_map(address_map &map)
 	map(0x1000, 0x1003).mirror(0x0ffc).rw(m_pia, FUNC(pia6821_device::read), FUNC(pia6821_device::write));
 	map(0x2000, 0x2001).mirror(0x0ffe).r(TMS9929_TAG, FUNC(tms9928a_device::read));
 	map(0x3000, 0x3001).mirror(0x0ffe).w(TMS9929_TAG, FUNC(tms9928a_device::write));
-	map(0x4000, 0x7fff).bankr(BANK_ROM2);
-	map(0x8000, 0xbfff).bankr(BANK_ROM1);
+	map(0x4000, 0x7fff).rom().share(BANK_ROM2);
+	map(0x8000, 0xbfff).rom().share(BANK_ROM1);
 //  map(0xc000, 0xe7ff).bankrw(3);
 	map(0xe800, 0xe800).w(m_cent_data_out, FUNC(output_latch_device::write));
 	map(0xe801, 0xe801).r("cent_status_in", FUNC(input_buffer_device::read));
@@ -184,8 +184,8 @@ void laser2001_state::lasr2001_map(address_map &map)
 	map(0x1000, 0x1003).mirror(0x0ffc).rw(m_pia, FUNC(pia6821_device::read), FUNC(pia6821_device::write));
 	map(0x2000, 0x2001).mirror(0x0ffe).r(TMS9929_TAG, FUNC(tms9928a_device::read));
 	map(0x3000, 0x3001).mirror(0x0ffe).w(TMS9929_TAG, FUNC(tms9928a_device::write));
-	map(0x4000, 0x7fff).bankrw(BANK_ROM2);
-	map(0x8000, 0xbfff).bankrw(BANK_ROM1);
+	map(0x4000, 0x7fff).ram().share(BANK_ROM2);
+	map(0x8000, 0xbfff).ram().share(BANK_ROM1);
 	map(0xc000, 0xffff).rom().region(M6502_TAG, 0);
 }
 
diff --git a/src/mame/includes/cps3.h b/src/mame/includes/cps3.h
index 6b789a56765..1db58e099dd 100644
--- a/src/mame/includes/cps3.h
+++ b/src/mame/includes/cps3.h
@@ -38,7 +38,7 @@ public:
 				 {*this, "simm7.%u", 0U}}
 		, m_mainram(*this, "mainram")
 		, m_spriteram(*this, "spriteram")
-		, m_colourram(*this, "colourram")
+		, m_colourram(*this, "colourram", 0x40000, ENDIANNESS_BIG)
 		, m_ppu_gscroll(*this, "ppu_gscroll_regs")
 		, m_tilemap_regs(*this, "ppu_tmap_regs")
 		, m_ppu_crtc_zoom(*this, "ppu_crtc_zoom")
@@ -92,7 +92,7 @@ protected:
 
 	required_shared_ptr<u32> m_mainram;
 	required_shared_ptr<u32> m_spriteram;
-	required_shared_ptr<u16> m_colourram;
+	memory_share_creator<u16> m_colourram;
 	required_shared_ptr<u32> m_ppu_gscroll;
 	required_shared_ptr<u32> m_tilemap_regs;
 	required_shared_ptr<u32> m_ppu_crtc_zoom;