; PI=16arctan(1/5)-4arctan(1/239)

	ORG 0000H

; 1–œŒ…
BIN_SIZE	EQU 4153+4	; 10000 * log(10) / log(100H)
BCD_SIZE	EQU (10000+10)/2
; �猅
;BIN_SIZE	EQU 416+4	; 1000 * log(10) / log(100H)
;BCD_SIZE	EQU (1000+10)/2

WORK1		EQU 01000H
WORK2		EQU 06000H
WORK3		EQU 0B000H
BCD_RESULT	EQU 06000H
WORK_BASE_H	EQU 0AH

WORK_BASE	EQU WORK_BASE_H*100H
PBIN_SIZE	EQU WORK_BASE-2
PBCD_SIZE	EQU WORK_BASE-4
PWORK2_SKIP	EQU WORK_BASE-6
MUL100TBL_H	EQU WORK_BASE_H
BCDTBL_H	EQU WORK_BASE_H+2

;

ENTRY:
	LD HL,BIN_SIZE
	LD (PBIN_SIZE),HL
	LD HL,BCD_SIZE
	LD (PBCD_SIZE),HL
ENTRY2:
	DI

CALC1:
	LD HL,WORK2
	LD A,16
	CALL SET_WORK
	LD HL,WORK2
	LD D,H
	LD E,L
	LD IX,5
	CALL MPDIV15
	LD HL,WORK2
	LD DE,WORK1
	LD BC,(PBIN_SIZE)
	LDIR
	LD IY,1
CALC1_L1:
	LD HL,WORK2
	CALL CHECK_WORK
	JR C,CALC1_END
	LD (PWORK2_SKIP),BC
	LD HL,WORK2
	LD D,H
	LD E,L
	LD IX,5*5
	CALL MPDIV15
	LD HL,WORK2
	CALL CHECK_WORK
	JR C,CALC1_END
	LD (PWORK2_SKIP),BC
	INC IY
	INC IY
	LD HL,WORK2
	LD DE,WORK3
	PUSH IY
	POP IX
	CALL MPDIV15
	LD HL,WORK3
	CALL CHECK_WORK
	JR C,CALC1_END
	PUSH IY
	POP BC
	LD A,C
	LD HL,WORK3
	LD DE,WORK1
	AND 02H
	JR NZ,CALC1_L2
	CALL MPADD
	JR CALC1_L1
CALC1_L2:
	CALL MPSUB
	JR CALC1_L1
CALC1_END:

CALC2:
	LD HL,WORK2
	LD A,4
	CALL SET_WORK
	LD HL,WORK2
	LD D,H
	LD E,L
	LD IX,239
	CALL MPDIV15
	LD HL,WORK2
	LD DE,WORK1
	CALL MPSUB
	LD IY,1
CALC2_L1:
	LD HL,WORK2
	CALL CHECK_WORK
	JR C,CALC2_END
	LD (PWORK2_SKIP),BC
	LD HL,WORK2
	LD D,H
	LD E,L
	LD IX,239*239
	CALL MPDIV16
	LD HL,WORK2
	CALL CHECK_WORK
	JR C,CALC2_END
	LD (PWORK2_SKIP),BC
	INC IY
	INC IY
	LD HL,WORK2
	LD DE,WORK3
	PUSH IY
	POP IX
	CALL MPDIV15
	LD HL,WORK3
	CALL CHECK_WORK
	JR C,CALC2_END
	PUSH IY
	POP BC
	LD A,C
	LD HL,WORK3
	LD DE,WORK1
	AND 02H
	JR NZ,CALC2_L2
	CALL MPSUB
	JR CALC2_L1
CALC2_L2:
	CALL MPADD
	JR CALC2_L1
CALC2_END:

CONVERT:
	CALL MAKE_BCDTBL
	LD HL,WORK1
	LD DE,BCD_RESULT
	LD BC,(PBIN_SIZE)
	LD IX,(PBCD_SIZE)
	CALL BIN2BCD

	EI
	RET

; [HL..HL+(PBIN_SIZE)-1] = A
SET_WORK:
	LD BC,(PBIN_SIZE)
	PUSH HL
	LD D,H
	LD E,L
	INC DE
	DEC BC
	LD (HL),0
	LDIR
	POP HL
	LD (HL),A
	LD HL,0
	LD (PWORK2_SKIP),HL
	RET

; check [HL..HL+(PBIN_SIZE)-1]
; out: if []==0 CF=1 else CF=0,BC=WORK2_SKIP
CHECK_WORK:
	LD DE,(PBIN_SIZE)
	LD BC,(PWORK2_SKIP)
	ADD HL,BC
	EX DE,HL
	SBC HL,BC
	JR CHECK_WORK_L2
CHECK_WORK_L1:
	LD A,(DE)
	OR A
	RET NZ
	INC DE
	DEC HL
	INC BC
CHECK_WORK_L2:
	LD A,H
	OR L
	JP NZ,CHECK_WORK_L1
	SCF
	RET

; [DE..DE+(PBIN_SIZE)-1] += [HL..HL+(PBIN_SIZE)-1]
MPADD:
	LD BC,(PBIN_SIZE)
	ADD HL,BC
	DEC HL
	EX DE,HL
	ADD HL,BC
	DEC HL
	EX DE,HL
	PUSH HL
	LD H,B
	LD L,C
	LD BC,(PWORK2_SKIP)
	SBC HL,BC
	DEC HL
	INC L
	INC H
	LD C,H
	LD B,L
	POP HL
MPADD_L1:
	LD A,(DE)
	ADC A,(HL)
	LD (DE),A
	DEC DE
	DEC HL
	DJNZ MPADD_L1
	DEC C
	JR NZ,MPADD_L1
	RET NC
	EX DE,HL
MPADD_L2:
	INC (HL)
	DEC HL
	JR Z,MPADD_L2
	RET

; [DE..DE+(PBIN_SIZE)-1] -= [HL..HL+(PBIN_SIZE)-1]
MPSUB:
	LD BC,(PBIN_SIZE)
	ADD HL,BC
	DEC HL
	EX DE,HL
	ADD HL,BC
	DEC HL
	EX DE,HL
	PUSH HL
	LD H,B
	LD L,C
	LD BC,(PWORK2_SKIP)
	SBC HL,BC
	DEC HL
	INC L
	INC H
	LD C,H
	LD B,L
	POP HL
MPSUB_L1:
	LD A,(DE)
	SBC A,(HL)
	LD (DE),A
	DEC DE
	DEC HL
	DJNZ MPSUB_L1
	DEC C
	JR NZ,MPSUB_L1
	RET NC
WSUB_L2:
	LD A,(DE)
	DEC A
	LD (DE),A
	DEC DE
	INC A
	JR Z,WSUB_L2
	RET

; [DE..DE+(PBIN_SIZE)-1] = [HL..HL+(PBIN_SIZE)-1] / IX (IX < 8000H)
MPDIV15:
	LD BC,(PWORK2_SKIP)
	ADD HL,BC
	EX DE,HL
	ADD HL,BC
	EX DE,HL
	PUSH HL
	LD HL,(PBIN_SIZE)
	SBC HL,BC
	DEC HL
	INC L
	INC H
	LD C,H
	LD B,L
	POP HL
	PUSH IX
	EXX
	POP DE
	LD HL,0
	EXX
MPDIV15_L1:
	LD A,(HL)
	INC HL
	EXX

	ADD A,A
	ADC HL,HL
	SBC HL,DE
	JR NC,MPDIV15_LB1
	ADD HL,DE
MPDIV15_LB1:
	ADC A,A
	ADC HL,HL
	SBC HL,DE
	JR NC,MPDIV15_LB2
	ADD HL,DE
MPDIV15_LB2:
	ADC A,A
	ADC HL,HL
	SBC HL,DE
	JR NC,MPDIV15_LB3
	ADD HL,DE
MPDIV15_LB3:
	ADC A,A
	ADC HL,HL
	SBC HL,DE
	JR NC,MPDIV15_LB4
	ADD HL,DE
MPDIV15_LB4:
	ADC A,A
	ADC HL,HL
	SBC HL,DE
	JR NC,MPDIV15_LB5
	ADD HL,DE
MPDIV15_LB5:
	ADC A,A
	ADC HL,HL
	SBC HL,DE
	JR NC,MPDIV15_LB6
	ADD HL,DE
MPDIV15_LB6:
	ADC A,A
	ADC HL,HL
	SBC HL,DE
	JR NC,MPDIV15_LB7
	ADD HL,DE
MPDIV15_LB7:
	ADC A,A
	ADC HL,HL
	SBC HL,DE
	JR NC,MPDIV15_LB8
	ADD HL,DE
MPDIV15_LB8:
	ADC A,A
	CPL

	EXX
	LD (DE),A
	INC DE
	DJNZ MPDIV15_L1
	DEC C
	JR NZ,MPDIV15_L1
	RET

; [DE..DE+(PBIN_SIZE)-1] = [HL..HL+(PBIN_SIZE)-1] / IX
MPDIV16:
	LD BC,(PWORK2_SKIP)
	ADD HL,BC
	EX DE,HL
	ADD HL,BC
	EX DE,HL
	PUSH HL
	LD HL,(PBIN_SIZE)
	SBC HL,BC
	DEC HL
	INC L
	INC H
	LD C,H
	LD B,L
	POP HL
	PUSH IX
	EXX
	POP DE
	LD A,E
	CPL
	LD C,A
	LD A,D
	CPL
	LD B,A
	INC BC
	LD HL,0
	EXX
MPDIV16_L1:
	LD A,(HL)
	INC HL
	EXX

	ADD A,A
	ADC HL,HL
	JR NC,MPDIV16_LB1_1
	ADD HL,BC
	JP MPDIV16_LB1_2
MPDIV16_LB1_1:
	SBC HL,DE
	JR NC,MPDIV16_LB1_2
	ADD HL,DE
MPDIV16_LB1_2:
	ADC A,A
	ADC HL,HL
	JR NC,MPDIV16_LB2_1
	ADD HL,BC
	JP MPDIV16_LB2_2
MPDIV16_LB2_1:
	SBC HL,DE
	JR NC,MPDIV16_LB2_2
	ADD HL,DE
MPDIV16_LB2_2:
	ADC A,A
	ADC HL,HL
	JR NC,MPDIV16_LB3_1
	ADD HL,BC
	JP MPDIV16_LB3_2
MPDIV16_LB3_1:
	SBC HL,DE
	JR NC,MPDIV16_LB3_2
	ADD HL,DE
MPDIV16_LB3_2:
	ADC A,A
	ADC HL,HL
	JR NC,MPDIV16_LB4_1
	ADD HL,BC
	JP MPDIV16_LB4_2
MPDIV16_LB4_1:
	SBC HL,DE
	JR NC,MPDIV16_LB4_2
	ADD HL,DE
MPDIV16_LB4_2:
	ADC A,A
	ADC HL,HL
	JR NC,MPDIV16_LB5_1
	ADD HL,BC
	JP MPDIV16_LB5_2
MPDIV16_LB5_1:
	SBC HL,DE
	JR NC,MPDIV16_LB5_2
	ADD HL,DE
MPDIV16_LB5_2:
	ADC A,A
	ADC HL,HL
	JR NC,MPDIV16_LB6_1
	ADD HL,BC
	JP MPDIV16_LB6_2
MPDIV16_LB6_1:
	SBC HL,DE
	JR NC,MPDIV16_LB6_2
	ADD HL,DE
MPDIV16_LB6_2:
	ADC A,A
	ADC HL,HL
	JR NC,MPDIV16_LB7_1
	ADD HL,BC
	JP MPDIV16_LB7_2
MPDIV16_LB7_1:
	SBC HL,DE
	JR NC,MPDIV16_LB7_2
	ADD HL,DE
MPDIV16_LB7_2:
	ADC A,A
	ADC HL,HL
	JR NC,MPDIV16_LB8_1
	ADD HL,BC
	JP MPDIV16_LB8_2
MPDIV16_LB8_1:
	SBC HL,DE
	JR NC,MPDIV16_LB8_2
	ADD HL,DE
MPDIV16_LB8_2:
	ADC A,A
	CPL

	EXX
	LD (DE),A
	INC DE
	DJNZ MPDIV16_L1
	DEC C
	JR NZ,MPDIV16_L1
	RET

; 100”{ƒe�[ƒuƒ‹‚ÆBCD•ÏŠ·ƒe�[ƒuƒ‹‚ð�ì�¬
MAKE_BCDTBL:
	LD HL,MUL100TBL_H*100H
	LD D,L
	LD E,L
	LD BC,100
MKBCDT_L1:
	LD (HL),E
	INC H
	LD (HL),D
	DEC H
	EX DE,HL
	ADD HL,BC
	EX DE,HL
	INC L
	JR NZ,MKBCDT_L1

	LD HL,BCDTBL_H*100H
	XOR A
MKBCDT_L2:
	LD (HL),A
	INC L
	ADD A,1
	DAA
	JR NC,MKBCDT_L2
	RET

; [DE..DE+IX] = packed BCD([HL..HL+BC-1])
BIN2BCD:
	LD A,(HL)
	LD (DE),A
	INC DE
	DEC BC
	ADD HL,BC
	EXX
	PUSH IX
	POP BC
	LD DE,54426	; floor(10000H * log(100) / log(100H))
	LD HL,0
BIN2BCD_L1:
	EXX
	PUSH HL
	PUSH BC
	PUSH DE
	DEC BC
	INC C
	INC B
	LD A,C
	LD C,B
	LD B,A
	XOR A
	LD D,MUL100TBL_H
BIN2BCD_L2:
	LD E,(HL)
	EX DE,HL
	ADC A,(HL)
	EX DE,HL
	LD (HL),A
	DEC HL
	INC D
	LD A,(DE)
	DEC D
	DJNZ BIN2BCD_L2
	DEC C
	JR NZ,BIN2BCD_L2
	ADC A,B
	LD D,BCDTBL_H
	LD E,A
	LD A,(DE)
	POP DE
	LD (DE),A
	INC DE
	POP BC
	POP HL
	EXX
	ADD HL,DE
	JR NC,BIN2BCD_L4
	EXX
	DEC HL
	DEC BC
	LD A,B
	OR C
	JR NZ,BIN2BCD_L3
	INC HL
	INC BC
BIN2BCD_L3:
	EXX
BIN2BCD_L4:
	DEC BC
	LD A,B
	OR C
	JR NZ,BIN2BCD_L1
	RET

	END