.Z80
;
; EQUATES
;
CR	EQU	0DH
LF	EQU	0AH
;
; CALCULATE DAYS AND YEAR,MONTH,DAYS
;
START:	LD	(SPSAVE),SP
	LD	SP,STACK
	LD	A,(00080H)
	ADD	A,81H
	LD	H,0
	LD	L,A
	LD	(HL),0
	LD	HL,00081H
	CALL	BLANK
	CP	'/'
	JP	NZ,START0
	LD	DE,EXPLA
	LD	C,9
	CALL	5
	JP	EXIT
;
EXPLA:	DEFM	'DATE. Date 03-01-86. Version 5.0'
	DEFB	CR,LF,CR,LF
	DEFM	'With this program you can get and set the current date and time'
	DEFB	CR,LF,CR,LF
	DEFM	'usage :  ''DATE''                   gives current date and time'
	DEFB	CR,LF
	DEFM	'         ''DATE dd/mm/yy hh:mm:ss'' sets current date and time'
	DEFB	CR,LF
	DEFM	'         ''DATE s[et]''             sets current date and time in dialog mode'
	DEFB	CR,LF
	DEFM	'         ''DATE c[ontinuous]''      display date and time continuous'
	DEFB	CR,LF
	DEFM	'         ''DATE //''                display this help info'
	DEFB	'$'

START0:	CP	0
	JP	Z,GET
	CP	'C'
	JP	Z,CONT
	CP	'c'
	JP	Z,CONT
	CP	'S'
	JP	Z,SET
	CP	's'
	JP	Z,SET
	PUSH	HL
	LD	DE,TIMEDT
	LD	C,200
	CALL	5
	POP	HL
	CALL	GETDAT
	JP	C,ERROR
	PUSH	HL
	LD	L,E			; YEAR
	LD	H,019H
	LD	E,B			; MONTH
	CALL	CONHEX
	CALL	CHKDAT
	JP	C,ERROR
	CALL	DAYS
	LD	(TIMEDT),BC
	POP	HL
	CALL	BLANK
	CP	0
	JR	Z,START1
	CALL	GETTIM
	JP	C,ERROR
	CALL	BLANK
	CP	0
	JP	NZ,ERROR
	CALL	CHKTIM
	JP	C,ERROR
	LD	A,B			; HOUR
	LD	(HOUR),A
	LD	A,C			; MINUTE
	LD	(MINUTE),A
	LD	A,E			; SECOND
	LD	(SECOND),A	
START1:	LD	DE,PRESS
	LD	C,9
	CALL	5
	LD	C,1
	CALL	5
	LD	DE,TIMEDT
	LD	C,201
	CALL	5
	LD	A,CR
	CALL	OUTCH
	LD	A,LF
	CALL	OUTCH
;	
GET:	LD	DE,TIMEDT
	LD	C,200
	CALL	5
	LD	BC,(TIMEDT)
	CALL	DMJ
	CALL	PRDMJ
	JP	EXIT
;
CONT:	LD	DE,TIMEDT
	LD	C,200
	CALL	5
	LD	BC,(TIMEDT)
	CALL	DMJ
	CALL	PRDMJ
CONT0:	LD	C,11
	CALL	5
	OR	A
	JR	NZ,CONT1
	LD	A,(SECOND)
	PUSH	AF
	LD	DE,TIMEDT
	LD	C,200
	CALL	5
	POP	AF
	LD	B,A
	LD	A,(SECOND)
	CP	B
	JR	Z,CONT0
	LD	A,CR
	CALL	OUTCH
	JR	CONT
CONT1:	LD	C,1
	CALL	5
	JP	EXIT
;
SET:	LD	DE,DATMSG
	LD	C,9
	CALL	5
	LD	DE,00080H
	LD	A,126
	LD	(00080H),A
	LD	C,10
	CALL	5
	LD	A,LF
	CALL	OUTCH
	LD	DE,DATE
	LD	C,200
	CALL	5
	LD	HL,(DATE)
	LD	(TIMEDT),HL
	LD	A,(00081H)
	ADD	A,82H
	LD	H,0
	LD	L,A
	LD	(HL),0
	LD	HL,00082H
	CALL	BLANK
	CP	0
	JR	Z,SET0
	CALL	GETDAT
	JP	C,ERROR
	CALL	BLANK
	CP	0
	JP	NZ,ERROR
	LD	L,E			; YEAR
	LD	H,019H
	LD	E,B			; MONTH
	CALL	CONHEX
	CALL	CHKDAT
	JP	C,ERROR
	CALL	DAYS
	LD	(TIMEDT),BC
SET0:	LD	A,0FFH
	LD	(TDFLAG),A
	LD	DE,TIMMSG
	LD	C,9
	CALL	5
	LD	DE,00080H
	LD	A,126
	LD	(00080H),A
	LD	C,10
	CALL	5
	LD	A,LF
	CALL	OUTCH
	LD	DE,DATE
	LD	C,200
	CALL	5
	LD	HL,DATE+2
	LD	DE,HOUR
	LD	BC,3
	LDIR
	LD	A,(00081H)
	ADD	A,82H
	LD	H,0
	LD	L,A
	LD	(HL),0
	LD	HL,00082H
	CALL	BLANK
	CP	0
	JP	Z,SET1
	CALL	GETTIM
	JP	C,ERROR
	CALL	BLANK
	CP	0
	JP	NZ,ERROR
	CALL	CHKTIM
	JP	C,ERROR
	LD	A,B			; HOUR
	LD	(HOUR),A
	LD	A,C			; MINUTE
	LD	(MINUTE),A
	LD	A,E			; SECOND
	LD	(SECOND),A	
SET1:	LD	DE,TIMEDT
	LD	C,201
	CALL	5
	JP	GET
;
ERROR:	LD	DE,ERRMSG
	LD	C,9
	CALL	5
	LD	A,(TDFLAG)
	OR	A
	JP	Z,SET
	JP	SET0
;
EXIT:	LD	SP,(SPSAVE)
	RET	
;
ERRMSG:	DEFM	'Error in data input'
	DEFB	CR,LF,'$'
;
DATMSG:	DEFM	'Enter today''s date (DD/MM/YY): $'
;
TIMMSG:	DEFM	'Enter the time (HH:MM:SS): $'
;
PRESS:	DEFM	'Press any key to set time $'
;
; GET DATE
;
GETDAT:	LD	A,(HL)
	INC	HL
	OR	A
	SCF
	RET	Z
	CALL	DIGIT
	JR	C,GETDAT
	DEC	HL
	CALL	NUMBER
	RET	C
	LD	C,E			; DAY
GETDT0:	LD	A,(HL)
	INC	HL
	OR	A
	SCF
	RET	Z
	CALL	DIGIT
	JR	C,GETDT0
	DEC	HL
	CALL	NUMBER
	RET	C
	LD	B,E			; MONTH
GETDT1:	LD	A,(HL)
	INC	HL
	OR	A
	SCF
	RET	Z
	CALL	DIGIT
	JR	C,GETDT1
	DEC	HL
	CALL	NUMBER			; YEAR
	RET	
;
; GET TIME
;
GETTIM:	LD	A,(HL)
	INC	HL
	OR	A
	SCF
	RET	Z
	CALL	DIGIT
	JR	C,GETTIM
	DEC	HL
	CALL	NUMBER
	RET	C
	LD	B,E			; HOUR
GETT0:	LD	A,(HL)
	INC	HL
	OR	A
	SCF
	RET	Z
	CALL	DIGIT
	JR	C,GETT0
	DEC	HL
	CALL	NUMBER
	RET	C
	LD	C,E			; MINUTE
	LD	E,0
GETT1:	LD	A,(HL)
	OR	A
	RET	Z
	INC	HL
	CALL	DIGIT
	JR	C,GETT1
	DEC	HL
	CALL	NUMBER			; SECOND
	RET
;
; CHECK DATE
;
CHKDAT:	LD	A,E
	OR	A
	SCF
	RET	Z
	CP	12+1
	CCF
	RET	C
	PUSH	HL
	LD	D,0
	LD	HL,DM-1
	ADD	HL,DE
	LD	B,(HL)			; DAYS IN MONTH
	POP	HL
	CP	2
	JR	NZ,CHKDT0
	CALL	LEAPYR
	JR	NZ,CHKDT0
	INC	B
CHKDT0:	LD	A,C
	OR	A
	SCF
	RET	Z
	CP	B
	RET	Z
	CCF
	RET
;
; CHECK TIME
;
CHKTIM:	LD	A,B
	CP	24H
	CCF
	RET	C
	LD	A,C
	CP	60H
	CCF
	RET	C
	LD	A,E
	CP	60H
	CCF
	RET
;
; CALCULATE DAYS
;  ENTRY : HL=YEAR (1978..2157)
;          E =MONTH (1..12)
;          C =DAYS (1..31)
;  EXIT  : BC=DAYS
;             FIRST DAY (00001) : SU 01-01-1978
;             LAST  DAY (65535) : SU 05-06-2157
;
DAYS:	LD	B,0
	PUSH	DE
	LD	DE,1978
DAYS0:	OR	A
	SBC	HL,DE
	ADD	HL,DE
	JR	Z,DAYS1
	PUSH	HL
	LD	HL,365
	ADD	HL,BC
	LD	B,H
	LD	C,L
	POP	HL
	EX	DE,HL
	CALL	LEAPYR
	EX	DE,HL
	INC	DE
	JR	NZ,DAYS0
	INC	BC
	JR	DAYS0
DAYS1:	POP	DE
	PUSH	HL
	LD	HL,DM
	LD	D,1
DAYS2:	LD	A,E
	CP	D
	JR	Z,DAYS4
	LD	A,C
	ADD	A,(HL)
	LD	C,A
	JR	NC,DAYS3
	INC	B
DAYS3:	INC	HL
	LD	A,D
	INC	D
	CP	2
	JR	NZ,DAYS2
	EX	(SP),HL
	CALL	LEAPYR
	EX	(SP),HL
	JR	NZ,DAYS2
	INC	BC
	JR	DAYS2
DAYS4:	POP	HL
	RET
;
; CALCULATE YEAR,MONTH,DAY
;  ENTRY : BC=DAYS
;             FIRST DAY (00001) : SU 01-01-1978
;             LAST  DAY (65535) : SU 05-06-2157
;  EXIT  : HL=YEAR (1978..2157)
;          D =DAYS IN LAST MONTH (1..31)
;          E =MONTH (1..12)
;          B =DAY OF WEEK (1..7, 1=SUNDAY)
;          C =DAYS (1..31)
;
DMJ:	PUSH	BC
	LD	HL,1978
DMJ0:	LD	DE,365
	CALL	LEAPYR
	JR	NZ,DMJ1
	INC	DE
DMJ1:	LD	A,E
	SUB	C
	LD	A,D
	SBC	A,B
	JR	NC,DMJ2
	LD	A,C
	SUB	E
	LD	C,A
	LD	A,B
	SBC	A,D
	LD	B,A
	INC	HL
	JR	DMJ0
DMJ2:	LD	E,1
	PUSH	HL
	LD	HL,DM
DMJ3:	LD	D,(HL)
	LD	A,E
	CP	2
	JR	NZ,DMJ4
	EX	(SP),HL
	CALL	LEAPYR
	EX	(SP),HL
	JR	NZ,DMJ4
	INC	D
DMJ4:	LD	A,D
	SUB	C
	LD	A,0
	SBC	A,B
	JR	NC,DMJ5
	LD	A,C
	SUB	D
	LD	C,A
	LD	A,B
	SBC	A,0
	LD	B,A
	INC	HL
	INC	E
	JR	DMJ3
DMJ5:	POP	HL
	EX	(SP),HL
	PUSH	BC
	DEC	HL
	LD	BC,16*256+7
	XOR	A
DMJ6:	RL	L
	RL	H
	RLA
	CP	C
	JR	C,DMJ7
	SUB	C
DMJ7:	DJNZ	DMJ6	
	INC	A
	POP	BC
	LD	B,A
	POP	HL
	RET
;
; CALCULATE LEAP YEAR CORRECTION
;  ENTRY : HL = YEAR
;  EXIT  : Z  = 1 CORRECTION NECCESARRY
;          Z  = 0 NO CORRECTION NEEDED
;
LEAPYR:	LD	A,L
	AND	3
	RET	NZ
	PUSH	HL
	PUSH	DE
	LD	A,-1
	LD	DE,100
	OR	A
LEAPY0:	INC	A
	SBC	HL,DE
	JR	NC,LEAPY0
	ADD	HL,DE
	LD	H,A
	LD	A,L
	OR	A
	JR	NZ,LEAPY1
	LD	A,H
	AND	3
	JR	LEAPY2
LEAPY1:	XOR	A
LEAPY2:	POP	DE
	POP	HL
	RET
;
; DAYS/MONTH
;
DM:	DEFB	31,28,31,30,31,30,31,31,30,31,30,31
;
; CONVERT DAYS,MONTH,YEAR TO HEX
;
CONHEX:	LD	A,C
	CALL	BCDHEX
	LD	C,A
	LD	A,E
	CALL	BCDHEX
	LD	E,A
	PUSH	DE
	LD	DE,100
	LD	A,L
	CALL	BCDHEX
	LD	L,A
	LD	A,H
	CALL	BCDHEX
	LD	H,0
	OR	A
	JR	Z,CONHX1
CONHX0:	ADD	HL,DE
	DEC	A
	JR	NZ,CONHX0
CONHX1:	LD	DE,1978
	OR	A
	SBC	HL,DE
	ADD	HL,DE
	JR	NC,CONHX2
	LD	DE,100
	ADD	HL,DE
CONHX2:	POP	DE
	RET
;
; PRINT: DAY IN WEEK,DAYS,MONTH,YEAR
;
PRDMJ:	PUSH	HL
	PUSH	BC
	LD	HL,DAYSWK-3
	LD	C,B
	LD	B,0
	ADD	HL,BC
	ADD	HL,BC
	ADD	HL,BC
	LD	A,(HL)
	INC	HL
	CALL	OUTCH
	LD	A,(HL)
	INC	HL
	CALL	OUTCH
	LD	A,(HL)
	CALL	OUTCH
	POP	BC
	POP	HL
	LD	A,' '
	CALL	OUTCH
	LD	A,C
	CALL	HEXBCD
	CALL	OUTBCD
	LD	A,'-'
	CALL	OUTCH
	PUSH	HL
	PUSH	DE
	LD	D,0
	LD	HL,MONTHS-3
	ADD	HL,DE
	ADD	HL,DE
	ADD	HL,DE
	LD	A,(HL)
	INC	HL
	CALL	OUTCH
	LD	A,(HL)
	INC	HL
	CALL	OUTCH
	LD	A,(HL)
	CALL	OUTCH
	POP	DE
	POP	HL
	LD	A,'-'
	CALL	OUTCH
	LD	A,E
	CALL	HEXBCD
	LD	E,A
	PUSH	DE
	LD	A,-1
	LD	DE,100
	OR	A
PRDMJ0:	INC	A
	SBC	HL,DE
	JR	NC,PRDMJ0
	ADD	HL,DE
	CALL	HEXBCD
	LD	H,A
	LD	A,L
	CALL	HEXBCD
	LD	L,A
	POP	DE
	LD	A,H
	CALL	OUTBCD
	LD	A,L
	CALL	OUTBCD
	LD	A,' '
	CALL	OUTCH
	LD	A,(HOUR)
	CALL	OUTBCD
	LD	A,':'
	CALL	OUTCH
	LD	A,(MINUTE)
	CALL	OUTBCD
	LD	A,':'
	CALL	OUTCH
	LD	A,(SECOND)
	CALL	OUTBCD
	RET
;
; DAYS IN WEEK
;
MONTHS:	DEFM	'JanFebMarAprMayJunJulAugSepOctNovDec'
;
DAYSWK:	DEFM	'SunMonTueWedThuFriSat'
;
; CONVERT HEX TO BCD
;
HEXBCD:	OR	A
	RET	Z
	PUSH	BC
	LD	B,A
	XOR	A
HXBCD0:	ADD	A,1
	DAA
	DJNZ	HXBCD0
	POP	BC
	RET
;
; CONVERT BCD TO HEX
;
BCDHEX:	OR	A
	RET	Z
	PUSH	BC
	LD	B,0
BCDHX0:	INC	B
	SUB	1
	DAA
	JR	NZ,BCDHX0
	LD	A,B
	POP	BC
	RET
;
; OUTPUT BCD CHAR
;
OUTBCD:	PUSH	AF
	RRCA
	RRCA
	RRCA
	RRCA
	AND	0FH
	ADD	A,'0'
	CALL	OUTCH
	POP	AF
	PUSH	AF
	AND	0FH
	ADD	A,'0'
	CALL	OUTCH
	POP	AF
	RET
;
; OUTPUT CHAR
;
OUTCH:	PUSH	AF
	PUSH	BC
	PUSH	DE
	PUSH	HL
	LD	E,A
	LD	C,2
	CALL	5
	POP	HL
	POP	DE
	POP	BC
	POP	AF
	RET
;
; INPUT NUMBER
;
NUMBER:	CALL	BLANK
	LD	A,(HL)
	CALL	DIGIT
	RET	C
	AND	0FH
	LD	E,A
	LD	D,0
NUMB0:	INC	HL
	LD	A,(HL)
	CALL	DIGIT
	CCF
	RET	NC
	EX	DE,HL
	ADD	HL,HL
	ADD	HL,HL
	ADD	HL,HL
	ADD	HL,HL
	AND	0FH
	ADD	A,L
	LD	L,A
	EX	DE,HL
	LD	A,D
	OR	A
	SCF
	RET	NZ
	JR	NUMB0
;
; BLANK INPUT
;
BLANK:	LD	A,(HL)
	CP	' '
	JR	Z,BLANK0
	CP	09H
	RET	NZ
BLANK0:	INC	HL
	JR	BLANK
;
; TEST DIGIT
;
DIGIT:	CP	'0'
	RET	C
	CP	'9'+1
	CCF
	RET
;
TDFLAG:	DEFB	0
;
TIMEDT:	DEFW	0
HOUR:	DEFB	0
MINUTE:	DEFB	0
SECOND:	DEFB	0
;
DATE:	DEFW	0
	DEFS	3
;
SPSAVE:	DEFS	2
	DEFS	64
STACK:
;
	END