diff --git a/libs/master.lib/bgm_set_tempo.asm b/libs/master.lib/bgm_set_tempo.asm
new file mode 100644
index 00000000..84b3a398
--- /dev/null
+++ b/libs/master.lib/bgm_set_tempo.asm
@@ -0,0 +1,66 @@
+; master library - BGM
+;
+; Description:
+;	テンポを変更する
+;
+; Function/Procedures:
+;	int bgm_set_tempo(int tempo);
+;
+; Parameters:
+;	tempo		設定するテンポ
+;
+; Returns:
+;	BGM_COMPLETE	正常終了
+;	BGM_EXTENT_ERR	テンポの値が異常
+;
+; Binding Target:
+;	Microsoft-C / Turbo-C / Turbo Pascal
+;
+; Running Target:
+;	PC-9801V
+;
+; Requiring Resources:
+;	CPU: V30
+;
+; Notes:
+;
+;
+; Assembly Language Note:
+;
+;
+; Compiler/Assembler:
+;	TASM 3.0
+;	OPTASM 1.6
+;
+; Author:
+;	femy(淀  文武)		: オリジナル・C言語版
+;	steelman(千野  裕司)	: アセンブリ言語版
+;
+; Revision History:
+;	93/12/19 Initial: b_s_temp.asm / master.lib 0.22 <- bgmlibs.lib 1.12
+
+func BGM_SET_TEMPO
+	mov	BX,SP
+	tempo	= (RETSIZE+0)*2
+	mov	CX,SS:[BX+tempo]
+	cmp	CX,TEMPOMIN
+	jl	short @@ILLEGAL
+	cmp	CX,TEMPOMAX
+	jg	short @@ILLEGAL
+
+	CLI
+
+	mov	glb.tp,CX
+	mov	AX,word ptr glb.clockbase
+	mov	DX,word ptr glb.clockbase+2
+	div	CX
+	mov	glb.tval,AX
+
+	STI
+
+	xor	AX,AX			; BGM_COMPLETE
+	ret	2
+@@ILLEGAL:
+	mov	AX,BGM_EXTENT_ERR
+	ret	2
+endfunc
diff --git a/th04_main.asm b/th04_main.asm
index 1c4e5e0d..9e2a69b5 100644
--- a/th04_main.asm
+++ b/th04_main.asm
@@ -6090,9 +6090,7 @@ loc_3818:
 loc_3826:
 		call	sub_3726
 		push	cx
-		nop
-		push	cs
-		call	near ptr sub_3D86
+		nopcall	bgm_set_tempo
 		jmp	short loc_3807
 ; ---------------------------------------------------------------------------
 		nop
@@ -6901,34 +6899,7 @@ loc_3D82:
 		retf
 sub_3D6C	endp
 
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_3D86	proc far
-					; sub_3DB4+12Dp
-		mov	bx, sp
-		mov	cx, ss:[bx+4]
-		cmp	cx, 1Eh
-		jl	short loc_3DAE
-		cmp	cx, 0F0h ; '�'
-		jg	short loc_3DAE
-		cli
-		mov	glb.tp, cx
-		mov	ax, word ptr glb.clockbase
-		mov	dx, word ptr glb.clockbase+2
-		div	cx
-		mov	glb.tval, ax
-		sti
-		xor	ax, ax
-		retf	2
-; ---------------------------------------------------------------------------
-
-loc_3DAE:
-		mov	ax, 0FFF3h
-		retf	2
-sub_3D86	endp
-
+include libs/master.lib/bgm_set_tempo.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -7058,9 +7029,7 @@ loc_3ECE:
 		mov	word ptr glb.clockbase+2, dx
 		mov	word ptr glb.clockbase, ax
 		push	78h ; 'x'
-		nop
-		push	cs
-		call	near ptr sub_3D86
+		nopcall	bgm_set_tempo
 		mov	bx, 3664h
 		xor	dx, dx
 		xor	ax, ax
diff --git a/th04_maine.asm b/th04_maine.asm
index e5190d1d..2beae8f0 100644
--- a/th04_maine.asm
+++ b/th04_maine.asm
@@ -3147,9 +3147,7 @@ loc_2E34:
 loc_2E42:
 		call	sub_2D42
 		push	cx
-		nop
-		push	cs
-		call	near ptr sub_33A2
+		nopcall	bgm_set_tempo
 		jmp	short loc_2E23
 ; ---------------------------------------------------------------------------
 		nop
@@ -3958,34 +3956,7 @@ loc_339E:
 		retf
 sub_3388	endp
 
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_33A2	proc far
-					; sub_33D0+12Dp
-		mov	bx, sp
-		mov	cx, ss:[bx+4]
-		cmp	cx, 1Eh
-		jl	short loc_33CA
-		cmp	cx, 0F0h ; '�'
-		jg	short loc_33CA
-		cli
-		mov	glb.tp, cx
-		mov	ax, word ptr glb.clockbase
-		mov	dx, word ptr glb.clockbase+2
-		div	cx
-		mov	glb.tval, ax
-		sti
-		xor	ax, ax
-		retf	2
-; ---------------------------------------------------------------------------
-
-loc_33CA:
-		mov	ax, 0FFF3h
-		retf	2
-sub_33A2	endp
-
+include libs/master.lib/bgm_set_tempo.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -4115,9 +4086,7 @@ loc_34EA:
 		mov	word ptr glb.clockbase+2, dx
 		mov	word ptr glb.clockbase, ax
 		push	78h ; 'x'
-		nop
-		push	cs
-		call	near ptr sub_33A2
+		nopcall	bgm_set_tempo
 		mov	bx, 1A74h
 		xor	dx, dx
 		xor	ax, ax
diff --git a/th04_op.asm b/th04_op.asm
index 31705c1b..8a96e6a6 100644
--- a/th04_op.asm
+++ b/th04_op.asm
@@ -3893,9 +3893,7 @@ loc_35D2:
 loc_35E0:
 		call	sub_34E0
 		push	cx
-		nop
-		push	cs
-		call	near ptr sub_3B40
+		nopcall	bgm_set_tempo
 		jmp	short loc_35C1
 ; ---------------------------------------------------------------------------
 		nop
@@ -4704,34 +4702,7 @@ loc_3B3C:
 		retf
 sub_3B26	endp
 
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_3B40	proc far
-					; sub_3B6E+12Dp
-		mov	bx, sp
-		mov	cx, ss:[bx+4]
-		cmp	cx, 1Eh
-		jl	short loc_3B68
-		cmp	cx, 0F0h ; '�'
-		jg	short loc_3B68
-		cli
-		mov	glb.tp, cx
-		mov	ax, word ptr glb.clockbase
-		mov	dx, word ptr glb.clockbase+2
-		div	cx
-		mov	glb.tval, ax
-		sti
-		xor	ax, ax
-		retf	2
-; ---------------------------------------------------------------------------
-
-loc_3B68:
-		mov	ax, 0FFF3h
-		retf	2
-sub_3B40	endp
-
+include libs/master.lib/bgm_set_tempo.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -4861,9 +4832,7 @@ loc_3C88:
 		mov	word ptr glb.clockbase+2, dx
 		mov	word ptr glb.clockbase, ax
 		push	78h ; 'x'
-		nop
-		push	cs
-		call	near ptr sub_3B40
+		nopcall	bgm_set_tempo
 		mov	bx, 2642h
 		xor	dx, dx
 		xor	ax, ax
diff --git a/th05_main.asm b/th05_main.asm
index e6da5891..695fa06f 100644
--- a/th05_main.asm
+++ b/th05_main.asm
@@ -5999,9 +5999,7 @@ loc_37B2:
 loc_37C0:
 		call	sub_36C0
 		push	cx
-		nop
-		push	cs
-		call	near ptr sub_3D20
+		nopcall	bgm_set_tempo
 		jmp	short loc_37A1
 ; ---------------------------------------------------------------------------
 		nop
@@ -6810,34 +6808,7 @@ loc_3D1C:
 		retf
 sub_3D06	endp
 
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_3D20	proc far
-					; sub_3D4E+12Dp
-		mov	bx, sp
-		mov	cx, ss:[bx+4]
-		cmp	cx, 1Eh
-		jl	short loc_3D48
-		cmp	cx, 0F0h ; '�'
-		jg	short loc_3D48
-		cli
-		mov	glb.tp, cx
-		mov	ax, word ptr glb.clockbase
-		mov	dx, word ptr glb.clockbase+2
-		div	cx
-		mov	glb.tval, ax
-		sti
-		xor	ax, ax
-		retf	2
-; ---------------------------------------------------------------------------
-
-loc_3D48:
-		mov	ax, 0FFF3h
-		retf	2
-sub_3D20	endp
-
+include libs/master.lib/bgm_set_tempo.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -6968,9 +6939,7 @@ loc_3E68:
 		mov	word ptr glb.clockbase+2, dx
 		mov	word ptr glb.clockbase, ax
 		push	78h ; 'x'
-		nop
-		push	cs
-		call	near ptr sub_3D20
+		nopcall	bgm_set_tempo
 		mov	bx, 2FAAh
 		xor	dx, dx
 		xor	ax, ax
diff --git a/th05_maine.asm b/th05_maine.asm
index db24fa7f..18c449ee 100644
--- a/th05_maine.asm
+++ b/th05_maine.asm
@@ -3593,9 +3593,7 @@ loc_2FBA:
 loc_2FC8:
 		call	sub_2EC8
 		push	cx
-		nop
-		push	cs
-		call	near ptr sub_3528
+		nopcall	bgm_set_tempo
 		jmp	short loc_2FA9
 ; ---------------------------------------------------------------------------
 		nop
@@ -4404,34 +4402,7 @@ loc_3524:
 		retf
 sub_350E	endp
 
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_3528	proc far
-					; sub_3556+12Dp
-		mov	bx, sp
-		mov	cx, ss:[bx+4]
-		cmp	cx, 1Eh
-		jl	short loc_3550
-		cmp	cx, 0F0h ; '�E
-		jg	short loc_3550
-		cli
-		mov	glb.tp, cx
-		mov	ax, word ptr glb.clockbase
-		mov	dx, word ptr glb.clockbase+2
-		div	cx
-		mov	glb.tval, ax
-		sti
-		xor	ax, ax
-		retf	2
-; ---------------------------------------------------------------------------
-
-loc_3550:
-		mov	ax, 0FFF3h
-		retf	2
-sub_3528	endp
-
+include libs/master.lib/bgm_set_tempo.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -4561,9 +4532,7 @@ loc_3670:
 		mov	word ptr glb.clockbase+2, dx
 		mov	word ptr glb.clockbase, ax
 		push	78h ; 'x'
-		nop
-		push	cs
-		call	near ptr sub_3528
+		nopcall	bgm_set_tempo
 		mov	bx, 26E8h
 		xor	dx, dx
 		xor	ax, ax
diff --git a/th05_op.asm b/th05_op.asm
index efae0fd7..cde54b3b 100644
--- a/th05_op.asm
+++ b/th05_op.asm
@@ -3013,9 +3013,7 @@ loc_2DF2:
 loc_2E00:
 		call	sub_2D00
 		push	cx
-		nop
-		push	cs
-		call	near ptr sub_3360
+		nopcall	bgm_set_tempo
 		jmp	short loc_2DE1
 ; ---------------------------------------------------------------------------
 		nop
@@ -3824,34 +3822,7 @@ loc_335C:
 		retf
 sub_3346	endp
 
-
-; =============== S U B	R O U T	I N E =======================================
-
-
-sub_3360	proc far
-					; sub_338E+12Dp
-		mov	bx, sp
-		mov	cx, ss:[bx+4]
-		cmp	cx, 1Eh
-		jl	short loc_3388
-		cmp	cx, 0F0h ; '�'
-		jg	short loc_3388
-		cli
-		mov	glb.tp, cx
-		mov	ax, word ptr glb.clockbase
-		mov	dx, word ptr glb.clockbase+2
-		div	cx
-		mov	glb.tval, ax
-		sti
-		xor	ax, ax
-		retf	2
-; ---------------------------------------------------------------------------
-
-loc_3388:
-		mov	ax, 0FFF3h
-		retf	2
-sub_3360	endp
-
+include libs/master.lib/bgm_set_tempo.asm
 
 ; =============== S U B	R O U T	I N E =======================================
 
@@ -3981,9 +3952,7 @@ loc_34A8:
 		mov	word ptr glb.clockbase+2, dx
 		mov	word ptr glb.clockbase, ax
 		push	78h ; 'x'
-		nop
-		push	cs
-		call	near ptr sub_3360
+		nopcall	bgm_set_tempo
 		mov	bx, 376Ch
 		xor	dx, dx
 		xor	ax, ax