diff --git a/src/mame/drivers/ympsr340.cpp b/src/mame/drivers/ympsr340.cpp
index 762c62ba8ae..9cea741e737 100644
--- a/src/mame/drivers/ympsr340.cpp
+++ b/src/mame/drivers/ympsr340.cpp
@@ -182,7 +182,7 @@ static INPUT_PORTS_START(psr340)
 	PORT_BIT(0x20, IP_ACTIVE_HIGH, IPT_OTHER) PORT_NAME("7") PORT_CODE(KEYCODE_7)
 
 	PORT_START("SD")
-	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_OTHER) PORT_NAME("O.T.S 5") PORT_CODE(KEYCODE_T)
+	PORT_BIT(0x01, IP_ACTIVE_HIGH, IPT_OTHER) PORT_NAME("O.T.S. 5") PORT_CODE(KEYCODE_T)
 	PORT_BIT(0x02, IP_ACTIVE_HIGH, IPT_OTHER) PORT_NAME("Harmony") PORT_CODE(KEYCODE_Z)
 	PORT_BIT(0x04, IP_ACTIVE_HIGH, IPT_OTHER) PORT_NAME("Sync Start") PORT_CODE(KEYCODE_X)
 	PORT_BIT(0x08, IP_ACTIVE_HIGH, IPT_OTHER) PORT_NAME("Utility") PORT_CODE(KEYCODE_C)