diff --git a/Source/HBIOS/tms.asm b/Source/HBIOS/tms.asm
index 114fd001..d8116d14 100644
--- a/Source/HBIOS/tms.asm
+++ b/Source/HBIOS/tms.asm
@@ -1214,7 +1214,11 @@ TMS_INITVDU_REG_1:
 	.DB	$00		; REG 6 - NO SPRITE GENERATOR TABLE
 	.DB	$F0		; REG 7 - WHITE ON BLACK
 	.DB	$88		; REG 8 - COLOUR BUS INPUT, DRAM 64K
+#IF (TICKFREQ == 50)
+	.DB	$02		; REG 9
+#ELSE
 	.DB	$00		; REG 9
+#ENDIF
 	.DB	$00		; REG 10 - COLOUR TABLE A14-A16 (TMS_FNTVADDR - $1000)
 ;
 #ELSE 		; _______TMS9918 REGISTER SET_______