diff --git a/Source/HBIOS/cfg_nabu.asm b/Source/HBIOS/cfg_nabu.asm
index 786d7390..372a26cd 100644
--- a/Source/HBIOS/cfg_nabu.asm
+++ b/Source/HBIOS/cfg_nabu.asm
@@ -192,7 +192,7 @@ CVDUENABLE	.EQU	FALSE		; CVDU: ENABLE CVDU VIDEO/KBD DRIVER (CVDU.ASM)
 GDCENABLE	.EQU	FALSE		; GDC: ENABLE 7220 GDC VIDEO/KBD DRIVER (GDC.ASM)
 TMSENABLE	.EQU	TRUE		; TMS: ENABLE TMS9918 VIDEO/KBD DRIVER (TMS.ASM)
 TMSMODE		.EQU	TMSMODE_NABU80	; TMS: DRIVER MODE: TMSMODE_[SCG|N8|MBC|MSX|MSX9958|MSXKBD|COLECO|DUO|NABU40|NABU80]
-TMSTIMENABLE	.EQU	FALSE		; TMS: ENABLE TIMER INTERRUPTS (REQUIRES IM1)
+TMSTIMENABLE	.EQU	TRUE		; TMS: ENABLE TIMER INTERRUPTS (REQUIRES IM1)
 VGAENABLE	.EQU	FALSE		; VGA: ENABLE VGA VIDEO/KBD DRIVER (VGA.ASM)
 VRCENABLE	.EQU	FALSE		; VRC: ENABLE VGARC VIDEO/KBD DRIVER (VRC.ASM)
 SCONENABLE	.EQU	FALSE		; SCON: ENABLE S100 CONSOLE DRIVER (SCON.ASM)
diff --git a/Source/HBIOS/nabu.asm b/Source/HBIOS/nabu.asm
index ec3a1cf7..bb4db4f4 100644
--- a/Source/HBIOS/nabu.asm
+++ b/Source/HBIOS/nabu.asm
@@ -81,7 +81,11 @@ NABU_SETPSG:
 	LD	A,14			; PSG R14 (PORT A DATA)
 	OUT	(NABU_RSEL),A		; SELECT IT
 #IF (INTMODE > 0)
+  #IF (TMSTIMENABLE == TRUE)
+	LD	A,%00110000		; ENABLE NABU KB & VDP INTS
+  #ELSE
 	LD	A,%00100000		; ENABLE NABU KB INTS
+  #ENDIF
 #ELSE
 	XOR	A
 #ENDIF
diff --git a/Source/HBIOS/tms.asm b/Source/HBIOS/tms.asm
index 0fd7fac3..7b0d7815 100644
--- a/Source/HBIOS/tms.asm
+++ b/Source/HBIOS/tms.asm
@@ -120,7 +120,7 @@ TMS_CMDREG	.EQU	$A1		; READ STATUS / WRITE REG SEL
 ;
 		DEVECHO	", IO="
 		DEVECHO	TMS_DATREG
-#IF TMSTIMENABLE
+#IF (TMSTIMENABLE & (INTMODE > 0))
 		DEVECHO	", INTERRUPTS ENABLED"
 #ENDIF
 		DEVECHO	"\n"
@@ -268,17 +268,26 @@ TMS_INIT1:
 	CALL	NABUKB_INIT		; INITIALIZE NABU KEYBOARD DRIVER
 #ENDIF
 
-#IF (INTMODE == 1 & TMSTIMENABLE)
+#IF (TMSTIMENABLE & (INTMODE > 0))
+;
+  #IF (INTMODE == 1)
 	; ADD IM1 INT CALL LIST ENTRY
-	LD	HL, TMS_TSTINT		; GET INT VECTOR
+	LD	HL,TMS_TSTINT		; GET INT VECTOR
 	CALL	HB_ADDIM1		; ADD TO IM1 CALL LIST
-
+  #ELSE
+	; INSTALL VECTOR
+	LD	HL,TMS_TSTINT
+	LD	(IVT(INT_VDP)),HL	; IVT INDEX
+  #ENDIF
+;
 	LD	A, (TMS_INITVDU_REG_1)
 	SET	TMSINTEN,A		; SET INTERRUPT ENABLE BIT
 	LD	(TMS_INITVDU_REG_1),A
 	LD	C, TMSCTRL1
 	CALL	TMS_SET
+;
 #ENDIF
+
 ;
 	; ADD OURSELVES TO VDA DISPATCH TABLE
 	LD	BC,TMS_FNTBL		; BC := FUNCTION TABLE ADDRESS
@@ -534,12 +543,14 @@ TMS_READ:
 ;----------------------------------------------------------------------
 ;
 TMS_SET:
+	HB_DI
 	OUT	(TMS_CMDREG),A		; WRITE IT
 	TMS_IODELAY
 	LD	A,C			; GET THE DESIRED REGISTER
 	OR	$80			; SET BIT 7
 	OUT	(TMS_CMDREG),A		; SELECT THE DESIRED REGISTER
 	TMS_IODELAY
+	HB_EI
 	RET
 ;
 ;----------------------------------------------------------------------
@@ -551,12 +562,14 @@ TMS_SET:
 TMS_WR:
 #IF ((TMSMODE == TMSMODE_MSX9958)  | (TMSMODE == TMSMODE_MBC) | (TMSMODE == TMSMODE_DUO) | (TMSMODE == TMSMODE_NABU80))
         ; CLEAR R#14 FOR V9958
+	HB_DI
         XOR     A
         OUT     (TMS_CMDREG), A
 	TMS_IODELAY
         LD      A, $80 | 14
         OUT     (TMS_CMDREG), A
 	TMS_IODELAY
+	HB_EI
 #ENDIF
 
 	PUSH	HL
@@ -566,12 +579,14 @@ TMS_WR:
 	RET
 ;
 TMS_RD:
+	HB_DI
 	LD	A,L
 	OUT	(TMS_CMDREG),A
 	TMS_IODELAY
 	LD	A,H
 	OUT	(TMS_CMDREG),A
 	TMS_IODELAY
+	HB_EI
 	RET
 ;
 ;----------------------------------------------------------------------
@@ -1045,11 +1060,11 @@ TMS_Z180IOX:
 ;
 #ENDIF
 
-#IF (INTMODE == 1 & TMSTIMENABLE)
+#IF (TMSTIMENABLE & (INTMODE > 0))
 TMS_TSTINT:
- 	IN      A, (TMS_CMDREG)		; TEST FOR INT FLAG
+ 	IN      A,(TMS_CMDREG)		; TEST FOR INT FLAG
 	AND	$80
-	JR	NZ, TMS_INTHNDL
+	JR	NZ,TMS_INTHNDL
 	AND	$00			; RETURN Z - NOT HANDLED
 	RET
 
diff --git a/Source/ver.inc b/Source/ver.inc
index 9971ed7e..93f95abc 100644
--- a/Source/ver.inc
+++ b/Source/ver.inc
@@ -2,7 +2,7 @@
 #DEFINE	RMN	5
 #DEFINE	RUP	0
 #DEFINE	RTP	0
-#DEFINE BIOSVER	"3.5.0-dev.37"
+#DEFINE BIOSVER	"3.5.0-dev.38"
 #define rmj	RMJ
 #define rmn	RMN
 #define rup	RUP
diff --git a/Source/ver.lib b/Source/ver.lib
index 4feb605b..d00f1741 100644
--- a/Source/ver.lib
+++ b/Source/ver.lib
@@ -3,5 +3,5 @@ rmn	equ	5
 rup	equ	0
 rtp	equ	0
 biosver	macro
-	db	"3.5.0-dev.37"
+	db	"3.5.0-dev.38"
 	endm