diff --git a/src/devices/bus/nes/mmc3_clones.cpp b/src/devices/bus/nes/mmc3_clones.cpp
index 4c0da2b4fa2..0fc9b3c1c93 100644
--- a/src/devices/bus/nes/mmc3_clones.cpp
+++ b/src/devices/bus/nes/mmc3_clones.cpp
@@ -2934,11 +2934,11 @@ void nes_bmc_f600_device::write_l(offs_t offset, u8 data)
 		m_reg = offset;
 
 		m_prg_base = (m_reg & 0x38) << 1;
-		m_prg_mask = 0x1f >> (BIT(m_reg, 5) ? 1 : 0);
+		m_prg_mask = 0x1f >> BIT(m_reg, 5);
 		set_prg(m_prg_base, m_prg_mask);
 
 		m_chr_base = (m_reg & 0x07) << 7;
-		m_chr_mask = 0xff >> (BIT(m_reg, 2) ? 0 : 1);
+		m_chr_mask = 0xff >> BIT(~m_reg, 2);
 		set_chr(m_chr_source, m_chr_base, m_chr_mask);
 	}
 }
diff --git a/src/mame/konami/rungun.cpp b/src/mame/konami/rungun.cpp
index db7dd28a097..1ba3e9d13be 100644
--- a/src/mame/konami/rungun.cpp
+++ b/src/mame/konami/rungun.cpp
@@ -182,7 +182,7 @@ uint16_t rungun_state::sysregs_r(offs_t offset, uint16_t mem_mask)
 			*/
 			{
 				uint8_t field_bit = m_screen->frame_number() & 1;
-				if (m_single_screen_mode == true)
+				if (m_single_screen_mode)
 					field_bit = 1;
 				return (m_system->read() & 0xfdff) | (field_bit << 9);
 			}
@@ -419,10 +419,10 @@ uint32_t rungun_state::screen_update_rng(screen_device &screen, bitmap_ind16 &bi
 	bitmap.fill(m_palette->black_pen(), cliprect);
 	screen.priority().fill(0, cliprect);
 	m_current_display_bank = m_screen->frame_number() & 1;
-	if (m_single_screen_mode == true)
+	if (m_single_screen_mode)
 		m_current_display_bank = 0;
 
-	if (m_video_priority_mode == false)
+	if (!m_video_priority_mode)
 	{
 		m_k053936->zoom_draw(screen, bitmap, cliprect, m_936_tilemap[m_current_display_bank], 0, 0, 1);
 		m_k055673->k053247_sprites_draw(bitmap, cliprect);
@@ -463,7 +463,7 @@ void rungun_state::sprite_dma_trigger(void)
 {
 	uint32_t src_address;
 
-	if (m_single_screen_mode == true)
+	if (m_single_screen_mode)
 		src_address = 1*0x2000;
 	else
 		src_address = m_current_display_bank*0x2000;