diff --git a/src/mame/machine/namcond1.cpp b/src/mame/machine/namcond1.cpp
index 891c08d23f7..3155577d111 100644
--- a/src/mame/machine/namcond1.cpp
+++ b/src/mame/machine/namcond1.cpp
@@ -85,7 +85,7 @@ WRITE16_MEMBER(namcond1_state::cuskey_w)
 
 		case (0x0c>>1):
 			m_ygv608->set_gfxbank((data & 0x0002) >> 1); // i think
-			// bit 0 used in abcheck
+			// bit 0 used in abcheck during garbage screens, tile/color select of some kind?
 			break;
 
 		default :