diff --git a/libs/master.lib/func.inc b/libs/master.lib/func.inc
index c3b62604..f9429204 100644
--- a/libs/master.lib/func.inc
+++ b/libs/master.lib/func.inc
@@ -1,6 +1,6 @@
 ; *Not* the original file. Changes include:
-; * replacement of DATASIZE and CODESIZE with TASM's @DataSize and @CodeSize
-;   variables
+; * a rewrite of the memory model conditional branches at the beginning to
+;   refer to TASM's @MODEL symbol
 ; * removal of the FUNC and ENDFUNC macros, which don't work with TASM's
 ;   strict alignment constraints. In turn, this means that we also need to
 ;   edit all source code files to not use these macros.
@@ -25,22 +25,19 @@
 ;	93/ 2/12 COMPACTMODEL, MEDIUMMODEL
 
 .list
-IFDEF NEARMODEL
+IF @MODEL LE 2
   CALLMODEL equ NEAR
   RETSIZE EQU 1
   DATASIZE EQU 1
-ENDIF
-IFDEF COMPACTMODEL
+ELSEIF @MODEL EQ 3
   CALLMODEL equ NEAR
   RETSIZE EQU 1
   DATASIZE EQU 2
-ENDIF
-IFDEF MEDIUMMODEL
+ELSEIF @MODEL EQ 4
   CALLMODEL equ FAR
   RETSIZE EQU 2
   DATASIZE EQU 1
-ENDIF
-IFDEF FARMODEL
+ELSEIF @MODEL EQ 5
   CALLMODEL equ FAR
   RETSIZE EQU 2
   DATASIZE EQU 2
@@ -86,7 +83,7 @@ lab	dw	?
 	ENDM
 
 
-IF @DataSize EQ 1
+IF DATASIZE EQ 2
 _push	MACRO reg
 	push reg
 	ENDM
@@ -159,7 +156,7 @@ ENDIF
 
 	; _call: かならず同一セグメントにあると判っているルーチンをcallする
 	; ときに使用するマクロ (94/1/1追加)
-IF @CodeSize EQ 1
+IF RETSIZE EQ 2
 _call	MACRO place
 	push	CS
 	call	near ptr place
diff --git a/libs/master.lib/graph_extmode.asm b/libs/master.lib/graph_extmode.asm
new file mode 100644
index 00000000..943789cc
--- /dev/null
+++ b/libs/master.lib/graph_extmode.asm
@@ -0,0 +1,106 @@
+; master library - 9821
+;
+; Description:
+;	9821拡張グラフィックモードの設定／取得
+;
+; Function/Procedures:
+;	unsigned graph_extmode( unsigned modmask, unsigned bhal ) ;
+;
+; Parameters:
+;	modmask:上位8bit: BHを操作するビットマスク
+;	modmask:下位8bit: ALを操作するビットマスク
+;	bhal	上位8bit: BHに設定する値(modmaskに対応したビットのみ有効)
+;		下位8bit: ALに設定する値(modmaskに対応したビットのみ有効)
+;
+;		ビットの内容:
+;			AL  b7 b6 b5 b4 b3 b2 b1 b0
+;						 ++- 0 ノンインターレース
+;						     1 インターレース
+;					++-++------- 00 15.98kHz
+;						     10 24.83kHz
+;						     11 31.47kHz
+;			BH  b7 b6 b5 b4 b3 b2 b1 b0
+;				  || ||	      ++-++- 00 20行
+;				  || ||		     01 25行
+;				  || ||		     10 30行
+;				  ++-++------------- 00 640x200(UPPER)
+;						     01 640x200(LOWER)
+;						     10 640x400
+;						     11 640x480
+;	
+;
+; Returns:
+;	実際に設定した値(almod=bhmod=0ならば取得した値)
+;	(上位8bit=BH, 下位8bit=ALね)
+;
+; Binding Target:
+;	Microsoft-C / Turbo-C / Turbo Pascal
+;
+; Running Target:
+;	PC-9801/9821, ただし9821でないと実行しても何もしないで 0 を返す。
+;
+; Requiring Resources:
+;	CPU: V30
+;
+; Notes:
+;	
+;
+; Assembly Language Note:
+;	
+;
+; Compiler/Assembler:
+;	TASM 3.0
+;	OPTASM 1.6
+;
+; Author:
+;	恋塚昭彦
+;
+; Revision History:
+;	94/ 1/ 8 Initial: grpextmd.asm/master.lib 0.22
+
+graph_extmode proc	; graph_extmode() {
+	xor	AX,AX
+	mov	ES,AX
+	test	byte ptr ES:[045ch],40h
+	jz	short G31_NOTMATE
+	;
+	modmask = (RETSIZE+1)*2
+	bhal = (RETSIZE+0)*2
+	mov	BX,SP
+	mov	CX,SS:[BX+modmask]
+	mov	DX,SS:[BX+bhal]
+	mov	AH,31h
+	int	18h		; 拡張グラフアーキテクチャモードの取得
+	mov	AH,BH
+	jcxz	short EXT_DONE	; modmask=0だったら読み取って終わり
+	and	DX,CX
+	not	CX
+	and	AX,CX
+	or	AX,DX
+	mov	CX,AX
+	mov	BH,AH
+
+	mov	AH,30h		; 拡張グラフアーキテクチャモードの設定
+	int	18h
+
+	test	TextShown,1
+	jz	short TEXT_SHOWN
+	mov	AH,0ch
+	int	18h		; テキスト画面の表示
+TEXT_SHOWN:
+	test	CL,1
+	jz	short NO_SETAREA
+	mov	AH,0eh		; 一つの表示領域の設定
+	xor	DX,DX
+	int	18h
+NO_SETAREA:
+	test	byte ptr ES:[0711h],1
+	jz	short CURSOR_HIDDEN
+	mov	AH,11h		; カーソルの表示
+	int	18h
+CURSOR_HIDDEN:
+	mov	AX,CX
+EXT_DONE:
+G31_NOTMATE:
+	ret	4
+endp		; }
diff --git a/th02_main.asm b/th02_main.asm
index 0923ae4f..263e8d72 100644
--- a/th02_main.asm
+++ b/th02_main.asm
@@ -18,6 +18,7 @@
 		locals
 
 include libs/BorlandC/RULES.ASI
+include libs/master.lib/func.inc
 
 ; ===========================================================================
 
@@ -3782,66 +3783,7 @@ sub_1614	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_166A	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	byte ptr es:loc_45B+1, 40h
-		jz	short locret_16BD
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_16BD
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_16A4
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_16A4:
-		test	cl, 1
-		jz	short loc_16AF
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_16AF:
-		test	es:byte_711, 1
-		jz	short loc_16BB
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_16BB:
-		mov	ax, cx
-
-locret_16BD:
-		retf	4
-sub_166A	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -5906,7 +5848,7 @@ sub_2740	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_166A
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_1E2C6, 33FFh
diff --git a/th02_maine.asm b/th02_maine.asm
index b25c19e5..a90608fa 100644
--- a/th02_maine.asm
+++ b/th02_maine.asm
@@ -18,6 +18,7 @@
 		locals
 
 include libs/BorlandC/RULES.ASI
+include libs/master.lib/func.inc
 
 ; ===========================================================================
 
@@ -3256,66 +3257,7 @@ sub_1276	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_12CC	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	byte ptr es:loc_45B+1, 40h
-		jz	short locret_131F
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_131F
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_1306
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1306:
-		test	cl, 1
-		jz	short loc_1311
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1311:
-		test	byte ptr es:loc_70E+3, 1
-		jz	short loc_131D
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_131D:
-		mov	ax, cx
-
-locret_131F:
-		retf	4
-sub_12CC	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -5296,7 +5238,7 @@ sub_233E	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_12CC
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_D6D8, 33FFh
diff --git a/th02_op.asm b/th02_op.asm
index ef463cc2..e984f316 100644
--- a/th02_op.asm
+++ b/th02_op.asm
@@ -18,6 +18,7 @@
 		locals
 
 include libs/BorlandC/RULES.ASI
+include libs/master.lib/func.inc
 
 ; ===========================================================================
 
@@ -2988,66 +2989,7 @@ sub_1290	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_12E6	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	byte ptr es:loc_45B+1, 40h
-		jz	short locret_1339
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_1339
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_1320
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1320:
-		test	cl, 1
-		jz	short loc_132B
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_132B:
-		test	es:byte_711, 1
-		jz	short loc_1337
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1337:
-		mov	ax, cx
-
-locret_1339:
-		retf	4
-sub_12E6	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -5332,7 +5274,7 @@ sub_2596	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_12E6
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_DBA2, 33FFh
diff --git a/th03_main.asm b/th03_main.asm
index 6aeb54ed..3e93a2f9 100644
--- a/th03_main.asm
+++ b/th03_main.asm
@@ -18,6 +18,7 @@
 		locals
 
 include libs/BorlandC/RULES.ASI
+include libs/master.lib/func.inc
 
 ; ===========================================================================
 
@@ -3387,66 +3388,7 @@ sub_14E4	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_153A	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	byte ptr es:loc_45B+1, 40h
-		jz	short locret_158D
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_158D
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_1574
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1574:
-		test	cl, 1
-		jz	short loc_157F
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_157F:
-		test	byte ptr es:loc_710+1, 1
-		jz	short loc_158B
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_158B:
-		mov	ax, cx
-
-locret_158D:
-		retf	4
-sub_153A	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -5288,7 +5230,7 @@ sub_20FC	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_153A
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_1DB02, 33FFh
diff --git a/th03_mainl.asm b/th03_mainl.asm
index 778061ef..fa0abec4 100644
--- a/th03_mainl.asm
+++ b/th03_mainl.asm
@@ -18,6 +18,7 @@
 		locals
 
 include libs/BorlandC/RULES.ASI
+include libs/master.lib/func.inc
 
 ; ===========================================================================
 
@@ -2484,66 +2485,7 @@ sub_EAC		endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_F02		proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	byte ptr es:loc_45B+1, 40h
-		jz	short locret_F55
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_F55
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_F3C
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_F3C:
-		test	cl, 1
-		jz	short loc_F47
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_F47:
-		test	byte ptr es:loc_710+1, 1
-		jz	short loc_F53
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_F53:
-		mov	ax, cx
-
-locret_F55:
-		retf	4
-sub_F02		endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -4519,7 +4461,7 @@ sub_1F6E	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_F02
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_EC36, 33FFh
diff --git a/th03_op.asm b/th03_op.asm
index ab24e2a2..682c77e3 100644
--- a/th03_op.asm
+++ b/th03_op.asm
@@ -18,6 +18,7 @@
 		locals
 
 include libs/BorlandC/RULES.ASI
+include libs/master.lib/func.inc
 
 ; ===========================================================================
 
@@ -2874,66 +2875,7 @@ sub_1186	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_11DC	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	byte ptr es:loc_45B+1, 40h
-		jz	short locret_122F
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_122F
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_1216
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1216:
-		test	cl, 1
-		jz	short loc_1221
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1221:
-		test	byte ptr es:loc_70F+2, 1
-		jz	short loc_122D
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_122D:
-		mov	ax, cx
-
-locret_122F:
-		retf	4
-sub_11DC	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -5080,7 +5022,7 @@ sub_22CA	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_11DC
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_DD92, 33FFh
diff --git a/th04_main.asm b/th04_main.asm
index 5d190149..31729ff8 100644
--- a/th04_main.asm
+++ b/th04_main.asm
@@ -657,7 +657,6 @@ loc_459:
 		xor	ax, ax
 
 loc_45B:
-					; sub_1CF4+4r
 		jmp	short loc_464
 ; ---------------------------------------------------------------------------
 		nop
@@ -4107,66 +4106,7 @@ sub_1CD0	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_1CF4	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	byte ptr es:loc_45B+1, 40h
-		jz	short locret_1D47
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_1D47
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_1D2E
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1D2E:
-		test	cl, 1
-		jz	short loc_1D39
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1D39:
-		test	byte ptr es:loc_711, 1
-		jz	short loc_1D45
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1D45:
-		mov	ax, cx
-
-locret_1D47:
-		retf	4
-sub_1CF4	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -5202,7 +5142,7 @@ sub_236C	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_1CF4
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_21AB2, 33FFh
diff --git a/th04_maine.asm b/th04_maine.asm
index f7990213..617571e0 100644
--- a/th04_maine.asm
+++ b/th04_maine.asm
@@ -655,7 +655,6 @@ loc_459:
 		xor	ax, ax
 
 loc_45B:
-					; sub_1218+4r
 		jmp	short loc_464
 ; ---------------------------------------------------------------------------
 		nop
@@ -2610,66 +2609,7 @@ sub_11C2	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_1218	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	byte ptr es:loc_45B+1, 40h
-		jz	short locret_126B
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_126B
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_1252
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1252:
-		test	cl, 1
-		jz	short loc_125D
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_125D:
-		test	byte ptr es:loc_711, 1
-		jz	short loc_1269
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1269:
-		mov	ax, cx
-
-locret_126B:
-		retf	4
-sub_1218	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -4406,7 +4346,7 @@ sub_2110	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_1218
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_E930, 33FFh
diff --git a/th04_op.asm b/th04_op.asm
index 61903525..a16606cc 100644
--- a/th04_op.asm
+++ b/th04_op.asm
@@ -655,7 +655,6 @@ loc_459:
 		xor	ax, ax
 
 loc_45B:
-					; sub_15C2+4r
 		jmp	short loc_464
 ; ---------------------------------------------------------------------------
 		nop
@@ -3090,66 +3089,7 @@ sub_156C	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_15C2	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	byte ptr es:loc_45B+1, 40h
-		jz	short locret_1615
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_1615
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_15FC
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_15FC:
-		test	cl, 1
-		jz	short loc_1607
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1607:
-		test	byte ptr es:loc_711, 1
-		jz	short loc_1613
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1613:
-		mov	ax, cx
-
-locret_1615:
-		retf	4
-sub_15C2	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -5024,7 +4964,7 @@ sub_2552	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_15C2
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_FB94, 33FFh
diff --git a/th05_main.asm b/th05_main.asm
index ea43caf2..56b88b47 100644
--- a/th05_main.asm
+++ b/th05_main.asm
@@ -665,7 +665,6 @@ loc_454:
 ; ---------------------------------------------------------------------------
 		db 89h
 byte_45C	db 87h
-					; sub_1E86+4r
 		db 72h,	3, 0A1h, 72h, 3, 0Bh, 6, 74h, 3, 5, 2 dup(0FFh)
 		db 1Bh,	0C0h, 3Bh, 6, 70h, 3, 74h, 29h,	0A3h, 70h, 3, 77h
 		db 26h,	0FAh, 0B0h, 0Bh, 0E6h, 70h, 0A0h, 77h, 3, 0E6h
@@ -4175,66 +4174,7 @@ sub_1E62	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_1E86	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	es:byte_45C, 40h
-		jz	short locret_1ED9
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_1ED9
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_1EC0
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1EC0:
-		test	cl, 1
-		jz	short loc_1ECB
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1ECB:
-		test	byte ptr es:loc_710+1, 1
-		jz	short loc_1ED7
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_1ED7:
-		mov	ax, cx
-
-locret_1ED9:
-		retf	4
-sub_1E86	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -5400,7 +5340,7 @@ sub_260E	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_1E86
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_2109A, 33FFh
diff --git a/th05_maine.asm b/th05_maine.asm
index e42c90a9..4999376d 100644
--- a/th05_maine.asm
+++ b/th05_maine.asm
@@ -666,7 +666,6 @@ loc_454:
 ; ---------------------------------------------------------------------------
 		db 89h
 byte_45C	db 87h
-					; sub_1392+4r
 		db 0BEh, 1, 0A1h, 0BEh,	1, 0Bh,	6, 0C0h, 1, 5, 2 dup(0FFh)
 		db 1Bh,	0C0h, 3Bh, 6, 0BCh, 1, 74h, 29h, 0A3h, 0BCh, 1
 		db 77h,	26h, 0FAh, 0B0h, 0Bh, 0E6h, 70h, 0A0h, 0C3h, 1
@@ -2802,66 +2801,7 @@ sub_133C	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_1392	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	es:byte_45C, 40h
-		jz	short locret_13E5
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_13E5
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_13CC
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_13CC:
-		test	cl, 1
-		jz	short loc_13D7
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_13D7:
-		test	byte ptr es:loc_710+1, 1
-		jz	short loc_13E3
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_13E3:
-		mov	ax, cx
-
-locret_13E5:
-		retf	4
-sub_1392	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -4734,7 +4674,7 @@ sub_2320	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_1392
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_10606, 33FFh
diff --git a/th05_op.asm b/th05_op.asm
index f054b523..a9b72ae4 100644
--- a/th05_op.asm
+++ b/th05_op.asm
@@ -665,7 +665,6 @@ loc_454:
 ; ---------------------------------------------------------------------------
 		db 89h
 byte_45C	db 87h
-					; sub_12A6+4r
 		db 0D4h, 4, 0A1h, 0D4h,	4, 0Bh,	6, 0D6h, 4, 5, 2 dup(0FFh)
 		db 1Bh,	0C0h, 3Bh, 6, 0D2h, 4, 74h, 29h, 0A3h, 0D2h, 4
 		db 77h,	26h, 0FAh, 0B0h, 0Bh, 0E6h, 70h, 0A0h, 0D9h, 4
@@ -2565,66 +2564,7 @@ sub_1250	endp
 
 ; ---------------------------------------------------------------------------
 		nop
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_12A6	proc far
-		xor	ax, ax
-		mov	es, ax
-		assume es:seg000
-		test	es:byte_45C, 40h
-		jz	short locret_12F9
-		mov	bx, sp
-		mov	cx, ss:[bx+6]
-		mov	dx, ss:[bx+4]
-		mov	ah, 31h	; '1'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		mov	ah, bh
-		jcxz	short locret_12F9
-		and	dx, cx
-		not	cx
-		and	ax, cx
-		or	ax, dx
-		mov	cx, ax
-		mov	bh, ah
-		mov	ah, 30h	; '0'
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-		test	TextShown, 1
-		jz	short loc_12E0
-		mov	ah, 0Ch
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_12E0:
-		test	cl, 1
-		jz	short loc_12EB
-		mov	ah, 0Eh
-		xor	dx, dx
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_12EB:
-		test	byte ptr es:loc_710+1, 1
-		jz	short loc_12F7
-		mov	ah, 11h
-		int	18h		; TRANSFER TO ROM BASIC
-					; causes transfer to ROM-based BASIC (IBM-PC)
-					; often	reboots	a compatible; often has	no effect at all
-
-loc_12F7:
-		mov	ax, cx
-
-locret_12F9:
-		retf	4
-sub_12A6	endp
-
+include libs/master.lib/graph_extmode.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -4412,7 +4352,7 @@ sub_2162	proc far
 		push	ax
 		push	ax
 		push	cs
-		call	near ptr sub_12A6
+		call	near ptr graph_extmode
 		and	ax, 0Ch
 		cmp	ax, 0Ch
 		mov	word_F7FC, 33FFh