*	REAL-TIME CLOCK UTILITY BY S. K. WEBB
*	RTCV23 -> Source re-created by Z80DIS 2.2
*	Z80DIS was written by Kenneth Gielow
*			Palo Alto, CA

	XTEXT	ASCII
	XTEXT	HOSEQU
	XTEXT	ESVAL
	XTEXT	ECDEF
	XTEXT	COMP
	XTEXT	DADA
	XTEXT	DADA2
	XTEXT	DU66
	XTEXT	UDD
	XTEXT	HOSDEF
	XTEXT	TYPTX
	XTEXT	HLIHL
	XTEXT	MU10
	XTEXT	MOVE
	

CLOCK 	EQU	240Q		Clock base port
S1	EQU	0		Seconds register
S10	EQU	1		Tens of Seconds
MI1	EQU	2		Minutes register
MI10	EQU	3		Tens of Minutes
H1	EQU	4		Hours register
H10	EQU	5		Tens of Hours
D1	EQU	6		Days register
D10	EQU	7		Tens of Days
MO1	EQU	8		Months register
MO10	EQU	9		Tens of Months
Y1	EQU	10		Years register
Y10	EQU	11		Tens of Years
W	EQU	12		Day of week reg.
REGD	EQU	13		Control Register D
REGE	EQU	14		Control Register E
REGF	EQU	15		Control Register F
*
*	Epson 7242 RTC register masks
*
*	Control Register D
*
RDHOLD	EQU	00000001B	Hold
RDBUSY	EQU	00000010B	Busy
RDIRQ	EQU	00000100B	IRQ Flag
RD30S	EQU	00001000B	30 Second correction
*
*	Control Register E
*
REMASK	EQU	00000001B	Mask
REITR	EQU	00000010B	ITRPT/STND
RET0	EQU	00000100B	t0
RET1	EQU	00001000B	t1
*
*	Control Register F
*
REFRST	EQU	00000001B	Reset
REFSTOP	EQU	00000010B	Stop
REF24	EQU	00000100B	1=24 hr. mode; 0=12 hr.
REFTEST	EQU	00001000B	Test must be 0 

	ORG	USERFWA

WELCOM	DB	'H8 RTC Support Utility v2.3 (08-APR-13 VERSION) '
	DB	'by Stanley K. Webb',ENL

USAGE	DB	'Usage=>RTC HELP',NL
	DB	'or   =>RTC SETUP',NL
	DB	'or   =>RTC',TAB,TAB
	DB	'(for TIME and DATE update)',ENL
*
*	Execution starts here
*
ENTRY	LXI	H,WELCOM	print signon message
	SCALL	.PRINT

	LXI	H,CKDVD		Load CK: device driver
	SCALL	.LOADD

	LXI	H,MEMTOP	Set RAM top
	SCALL	.SETTP

	MVI	A,EC.NEM	Not enough memory
	JC	ERROR

	SCALL	.VERS		HDOS Version

	PUSH	PSW
	MVI	A,EC.NCV	Not correct verson of HDOS
	JC	ERROR
	POP	PSW

	CPI	VERS
	JNC	VEROK

	MVI	A,EC.NCV	Not correct version of HDOS
	JMP	ERROR
*
*	Past initial error checking
*
VEROK	LXI	H,0
	DAD	SP		HL = SP (points to cmd line parameters)
	MVI	A,200Q		Subtract offset
	SUB	L		Look at low byte (L)
	LXI	D,CMDLINE	Destination
	MOV	C,A		String length
	CALL	STRCPY		Make a copy
*
*	Welcome user
*
	LXI	SP,WELCOM
	LXI	D,CMDLINE	Examine command line
	CALL	DOCMD		Process command line
*
*	HELP command
*
	DB	'HELP',0
	LXI	H,USAGE
	JNC	PREXIT		Print message and exit

	LDAX	D
	ANA	A
	JZ	J$23A0
	CALL	DOCMD
*
*	SETUP command
*
	DB	'SETUP',0
	JNC	J.238B
	CALL	DOCMD
*
*	SET command
*
	DB	'SET',0
	JNC	J.238B
*
*	No match, print error message
*
	MVI	A,BELL		Ring the bell
	SCALL	.SCOUT

	LXI	H,USAGE		And print usage reminder
	SCALL	.PRINT
*
*	Exit to HDOS
*
EXIT	MVI	A,0
	SCALL	.CLOSE
	XRA	A
	SCALL	.EXIT
*
*	Print message in (HL) and then exit
*
PREXIT	SCALL	.PRINT
	JMP	EXIT
*
*	Process error and then exit
*
ERROR	MVI	H,EC.ILR	Illegal Request
	SCALL	.ERROR
	JMP	EXIT

J.238B	CALL	CHKRTC		Check for the RTC

	CNC	READDOW		If have RTC get the DOW
*
*	Even if no RTC found proceed with date/time set
*
	CALL	INDATE		Prompt user for date
	CALL	INTIME		Prompt user for time
	CALL	SETCLK		Set clock device

	CALL	WRRTC		Write date, time and DOW to RTC
	JMP	J$2411

J$23A0	CALL	CHKRTC
	JC	NORTC

	CALL	RDRTC		Read and store RTC data
	CALL	GETTIM		Fetch S.TIME working copy
	CALL	SETCLK
*
*	Display the time
*
	CALL	$TYPTX
	DB	'RTC Time is',' '+200Q
	CALL	PRSTIM
*
*	Compute and store coded (HDOS) date
*
	CALL	CODEDT		Compute coded date
	SHLD	S.DATC		Store in RAM

	XCHG			DE = coded date
	LXI	H,S.DATE	Address of ASCII date
	CALL	$DAD		Decode Augustan Date
*
*	Display the day of week, and date
*
	CALL	$TYPTX
	DB	NL,'RTC Date is',' '+200Q
	CALL	PRNDAY		Print day of week
	CALL	$TYPTX
	DB	',',' '+200Q
	CALL	PRSDAT		Print system date

	CALL	$TYPTX
	DB	' (System Updated)',ENL
	JMP	EXIT


NORTC	CALL	$TYPTX
	DB	'NO RTC Found',ENL

J$2411	CALL	$TYPTX
	DB	'System Time is',' '+200Q

	CALL	PRSTIM		Print system time

	CALL	$TYPTX
	DB	' System Date is',' '+200Q

	CALL	PRSDAT		Print system date
	CALL	$TYPTX
	DB	ENL

	JMP	EXIT

* ==============================================
*
*	PRSDAT - Print System Date stored in S.DATE
*
* ==============================================
PRSDAT	MVI	C,9		Print 9 ASCII characters
	LXI	H,S.DATE	from System date
PRSD1	MOV	A,M		fetch byte
	INX	H		point to next
	SCALL	.SCOUT		print it
	DCR	C		count down
	JNZ	PRSD1		repeat 'til done...

	RET


* ==============================================
*
*	PRNDAY - print day of week
*
* ==============================================

PRNDAY	LDA	DOW		Fetch day of week
	ANI	7		low 3 bits
	ADD	A		*2 (word offset)
	LXI	H,DTAB		Table of day messages
	CALL	$DADA		point to entry
	CALL	$HLIHL		(HL) = entry
	CALL	$TYPTX.		type it!
	RET

DTAB	DW	MSUN
	DW	MMON
	DW	MTUE
	DW	MWED
	DW	MTHU
	DW	MFRI
	DW	MSAT
	DW	MERR

MSUN	DB	'Sunda','y'+200Q
MMON	DB	'Monda','y'+200Q
MTUE	DB	'Tuesda','y'+200Q
MWED	DB	'Wednesda','y'+200Q
MTHU	DB	'Thursda','y'+200Q
MFRI	DB	'Frida','y'+200Q
MSAT	DB	'Saturda','y'+200Q
MERR	DB	'PROGRAM ERR',200Q

MYMO	DB	6
MYDD	DB	15H
MYYY	DB	48H		YY

DOW	DB	0		Day of week
*
*	Our copy of S.TIME
*
MYTIME	EQU	*
MYHH	DB	0		Hours
MYMM	DB	0		Minutes
MYSS	DB	0		Seconds


* ==============================================
*
*	PRSTIM - Print System Date stored in S.TIME
*
* ==============================================

PRSTIM	MVI	C,3		3 bytes (hh, mm, ss)
	LXI	H,S.TIME	(HL) = S.TIME
	LXI	D,HMSLC		(DE) = ASCII time
	PUSH	D		Save address

PRST1	MOV	A,M		Fetch byte (hh, mm or ss)
	ANI	0F0H		High nibble
	RRC			Move to low
	RRC
	RRC
	RRC
	ADI	'0'		make ASCII
	STAX	D		and store
	INX	D		next output byte
	MOV	A,M		fetch byte again
	ANI	0FH		low nibble now
	ADI	'0'		make ASCII
	STAX	D		and store

	INX	D		skip ':'
	INX	D		next output byte
	INX	H		next input byte
	DCR	C		count down
	JNZ	PRST1		loop 'til done

	POP	H		Pop string address
	CALL	$TYPTX.		and print it

	RET

HMSLC	DB	'hh:mm:ss',200Q
HMSUC	DB	'HH:MM:SS',NL,200Q

	XTEXT	DDD
	XTEXT	MCU
	XTEXT	MLU
*
*	READLU - Read line and map to upper case
*
READLU	CALL	READLN
	RC
	JMP	$MLU

*
*	READLN - Read a line of text
*
*	ENTRY:	(HL) = buffer for storing line
*
READLN	PUSH	H		Save HL
READLN1	CALL	GETCH		Get a character

	CPI	CTLD		CTL-D -> exit with 'C' set
	JZ	READLN2

	MOV	M,A		Store character
	INX	H		point to next
	CPI	NL		Was ENTER hit?
	JNZ	READLN1		No, keep readin

	DCX	H		Enter was hit, go back one
	MVI	M,0		Replace NL with NUL
	INX	H		and point past it
	XCHG
	XTHL
	MOV	A,E
	SUB	L
	ANA	A
	POP	D
	RET

READLN2	POP	H
	STC
	RET

	XTEXT	SOB

* ==============================================
*
*	GETCH - Wait for a single character from the
*	console and read/return it
*
* ==============================================
GETCH	SCALL	.SCIN
	JC	GETCH
	RET

* ==============================================
*
*	PUTCH - Output a single character to the
*	console.
*
* ==============================================
PUTCH	SCALL	.SCOUT
	RET

	SPACE	4,10
** $CADY2K - CODE AUGUSTAN DATE IN HDOS Y2K FORMAT
** Modifications to $CAD by Stanley K. Webb
** More stringent checking of days in month by Stanley K. Webb
**
** $CADY2K  IS CALLED TO CODE AN AUGUSTAN DATE INTO A 16 BIT WORD:
**
**    7BITS 4BIT 5BITS
**  YYYYYYY MMMM DDDDD
**  1111110 0000 00000
**  5432109 8765 43210
**   00-99  1-12 1-31
**
**  FROM THE INPUT FORMAT: 'DD-MMM-YY'
**
** 	ENTRY	HL POINTS TO STRING
**	EXIT	'C' CLEAR IF OK
**		(DE) = 16 BIT VALUE
**		(HL) ADVANCED PAST '-YY'

$CAD	PUSH	H
	MVI	C,CADBL
	LXI	D,CADB
	CALL	$COMP
	JNZ	CAD0
	POP	D
	LXI	D,0		0 => NO-DATE
	ANA	A
	RET
CAD0	POP	H
	CALL	$DDD		DECODE DECIMAL DIGITS
	RC
	MOV	A,D
	ANA	A
	STC
	RNZ			TOO LARGE
	MOV	A,E
	ANA	A
	STC
	RZ			TOO SMALL FOR DD
	CPI	32
	CMC
	RC			TOO BIG
	STA	CAD.DD		SKW- SAVE DAY
	XCHG
	MVI	A,100000B	COUNT FIRST MONTH
	ADD	L
	MOV	L,A
	XCHG
	PUSH	D
	MOV	A,M
	INX	H
	CPI	'-'
	JNE	CAD2		FORMAT ERROR
	LXI	D,CADA
CAD1	LXI	B,3
	PUSH	H
	PUSH	D
	CALL	$COMP
	POP	D
	JE	CAD3
	POP	H
	INX	D
	INX	D
	INX	D
	XTHL
	MVI	A,100000B
	CALL	$DADA.
	XTHL
	LDAX	D		TEST FOR END OF STRING
	ANA	A
	JNZ	CAD1
CAD2	POP	H
	STC
	RET
CAD3	POP	B
	MOV	A,M
	CPI	'-'
	JNE	CAD2
	INX	H
	CALL	$DDD		DECODE DECIMAL DIGITS
	JC	CAD2		ERROR
	MOV	A,D
	ANA	A
	JNZ	CAD2		TOO BIG
	MOV	A,E
	JC	CAD2
	CPI	100		SKW- Y2K FIX
	JNC	CAD2
	POP	D
	STA	CAD.YY		SKW-SAVE YEAR
	ADD	A		SHIFT 1 BIT
	ADD	D
	MOV	D,A		MERGE DATA
**  CRACK OUT MONTH SKW **
	PUSH	H
	PUSH	D
	XCHG
	DAD	H
	DAD	H
	DAD	H
	MOV	A,H
	ANI	00001111B	ISOLATE MONTH
	STA	CAD.MON		SKW- SAVE MONTH
** AND TEST DAYS IN MONTH **
	CALL	DAYCHK		SKW- CODED THIS SUBROUTINE
	POP	D
	POP	H
	RET
CADA	DS	0
	DB	'JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC',0
CADB	DB	' No-Date '
CADBL	EQU	*-CADB

CAD.DD	DB	0
CAD.MON	DB	0
CAD.YY	DB	0

DAYCHK	LDA	CAD.YY
	LXI	HL,MNTHDNY		;NORMAL YEAR TABLE
	ANI	3H
	JNZ	DAYCHK1
	LXI	HL,MNTHDLY		;HAVE LEAP YEAR
DAYCHK1	LDA	CAD.MON
	DCR	A
	CALL	$DADA			;HL POINTS TO MAX DAYS IN MONTH
	LDA	CAD.DD
	DCR	A
	CMP	M
	CMC				FLAG AS TOO MANY DAYS
	RET

MNTHDNY	DB	31,28,31,30,31,30,31,31,30,31,30,31
MNTHDLY	DB	31,29,31,30,31,30,31,31,30,31,30,31


	SPACE	4,10
**	$DADY2K - DECODE AUGUSTAN DATE WORD IN HDOSY2K FORMAT
**
**  A MODIFIED VERSION OF $DAD BY STANLEY K. WEBB
**  DECODES A 16 BIT DATE ENCODED IN THE FOLLOWING FORMAT:
**
**    7BITS 4BIT 5BITS
**  YYYYYYY MMMM DDDDD
**  1111110 0000 00000
**  5432109 8765 43210
**   00-99  1-12 1-31
**
**  TO THE FORM 'DD-MMM-YY'
**
**	ENTRY	(DE)= 16 BIT PACKED DATE
**		(HL)= ADDRESS FOR DECODE

$DAD	MOV	A,D
	ORA	E
	JZ	DAD2		NO DATE
	MOV	B,D
	MOV	C,E
	LXI	D,32
	PUSH	H		SAVE ADDRESS
	CALL	$DU66		(DE)=DAY, (HL) YEAR & MONTH
	XTHL			HL=ADDRESS
	MOV	B,D
	MOV	C,E
	MOV	A,E
	ANA	A		BAD VALUE?
	JZ	DAD1		YES IF ZERO
	MVI	A,2
	CALL	$UDD		UNPACK DAY
	MVI	M,'-'
	INX	H
	POP	B		(BC)=YEAR & MONTH
	LXI	D,16
	PUSH	H		SAVE ADDRESS
	CALL	$DU66
	XTHL			(HL)= ADDRESS ((SP))= YEAR
	MOV	A,E
	ADD	A
	ADD	E		A=3*MONTH
	JZ	DAD1		ZERO IS BAD VALUE
	CPI	13*3
	JNC	DAD1		TOO BIG, BAD VALUE
	XCHG
	LXI	H,DADB-3	GET MONTH
	CALL	$DADA.
	LXI	B,3
	XCHG
	CALL	$MOVE		MOVE INTO PLACE
	MVI	M,'-'
	INX	H
	POP	B
	MOV	A,C
	ADI	0
	CPI	100		TOO BIG?
	CMC
	RC
	MOV	C,A
	MVI	A,2
	CALL	$UDD		UNPACK YEAR
	ANA	A
	RET
DAD1	POP	H
	STC
	RET
DAD2	LXI	B,DADCL
	LXI	D,DADC
	JMP	$MOVE
DADB	DB	'JanFebMarAprMayJunJulAugSepOctNovDec'
DADC	DB	' No-Date '
DADCL	EQU	*-DADC

* ==============================================
*
*	READDOW - Prompt for Day Of Week, read and validate
*	answer and store it locally.
*
* ==============================================
READDOW	CALL	$TYPTX
	DB	NL,'Input Day of Week index (1-7)',NL,NL
	DB	'1 = Sunday',NL
	DB	'2 = Monday',NL
	DB	'3 = Tuesday',NL
	DB	'4 = Wednesday',NL
	DB	'5 = Thursday',NL
	DB	'6 = Friday',NL
	DB	'7 = Saturday',ENL

	LXI	H,CMDLINE
	CALL	READLU		Read line (map to upper case)
	JC	EXIT		exit if CTL-D hit

	CALL	$SOB		Skip over ' ' and TAB

	ANA	A
	MVI	A,0		Default to Sunday
	STA	DOW
	RZ

	CALL	$DDD		Decode digits into DE

	MOV	A,D		Top byte must be 0
	ANA	A
	JNZ	BADDOW

	MOV	A,E		Bottom byte must be
	DCR	A		0-6 (entered as 1-7)
	CPI	7
	JNC	BADDOW

	STA	DOW		Valid DOW - save it!
	ANA	A
	RET


BADDOW	CALL	$TYPTX
	DB	'INVALID WEEK DAY INDEX ENTERED',BELL,ENL
	JMP	READDOW		Prompt for and read DOW

* ==============================================
*
*	INDATE - Input date as DD-MMM-YY
*
* ==============================================
INDATE	CALL	$TYPTX
	DB	NL,'Input DATE as DD-MMM-YY ?',' '+200Q

	LXI	H,CMDLINE
	CALL	READLU		Read line (map to upper case)

	JC	EXIT

	CALL	$SOB

	ANA	A
	JZ	INDATE		Try again

	CALL	$CAD		Code Augustan DAte

	JC	BADDATE

	XCHG
	SHLD	S.DATC
	XCHG
	LXI	H,S.DATE
	CALL	$DAD		Decode Augustan Date

	JC	ERROR1

	LDA	CAD.DD
	STA	MYDD
	LDA	CAD.MON
	STA	MYMO
	LDA	CAD.YY
	STA	MYYY
	MVI	A,3
	LXI	H,MYMO
	CALL	CODEVAL
	RET


BADDATE	CALL	$TYPTX
	DB	'INVALID DATE ENTERED',BELL,ENL
	JMP	INDATE


ERROR1	CALL	$TYPTX
	DB	BELL,'PROGRAM ERROR 1',ENL
	JMP	EXIT

* ==============================================
*
*	Input time in 24 hour format
*
* ==============================================
INTIME	CALL	$TYPTX		Prompt to enter time
	DB	NL,'Military Time ','('+200Q
	CALL	PRSTIM		Print current time
	CALL	$TYPTX
	DB	')?',' '+200Q

	LXI	H,CMDLINE
	CALL	READLU		Read line (map to upper case)

	JC	EXIT

	CALL	$SOB		Skip white space (HL)

	ANA	A
	JZ	INTIME

	CALL	$DDD

	MOV	A,D
	ANA	A
	JNZ	INVTIM		Invalid Time

	MOV	A,E
	CPI	24
	JNC	INVTIM		Invalid Time

	STA	MYHH		Hours good - save it!
*
*	Validate minutes
*
	MVI	A,':'		expecting ":"
	CMP	M		got it?
	JNZ	INVTIM		No! - invalid Time

	INX	H		next char
	CALL	$DDD

	MOV	A,D
	ANA	A
	JNZ	INVTIM		Invalid Time

	MOV	A,E
	CPI	60		Minutes must be < 60
	JNC	INVTIM		Invalid Time

	STA	MYMM		Minutes good - save it!

	XRA	A
	STA	MYSS		Zero our seconds value
	MVI	A,':'		expecting ":"
	CMP	M		got it?
	JNZ	CODETM		No! - done

	INX	H		next char
	CALL	$DDD

	MOV	A,D
	ANA	A
	JNZ	INVTIM		Invalid Time

	MOV	A,E
	CPI	60		Seconds must be < 60
	JNC	INVTIM		Invalid Time

	STA	MYSS		Seconds good - save it!
*
*	Now convert these decimal time values
*	into BCD coded ones
*
CODETM	MVI	A,3		Count 3 bytes (hh, mm, ss)
	LXI	H,MYTIME	Time location is here
*
*	Code each value
*
CODEVAL	PUSH	PSW
	PUSH	H
	MOV	C,M		(BC) = Value (hh, mm or ss)
	MVI	B,0
	LXI	D,10		(DE) = 10
	CALL	$DU66		(HL) = value/10

	MOV	A,L		Get tens value
	RLC			put it in high nibble
	RLC
	RLC
	RLC

	ORA	E		Put ones in low nibble

	POP	H		restore memory pointer
	MOV	M,A		save the value
	INX	H		point to next
	POP	PSW		restore count
	DCR	A		decrement
	JNZ	CODEVAL		and loop 'til done


GETTIM	LXI	H,S.TIME
	LXI	D,MYTIME
	LXI	B,3
	DI
	CALL	$MOVE
	EI
	RET


INVTIM	CALL	$TYPTX
	DB	' INVALID TIME ENTERED',BELL,ENL
	JMP	INTIME
*
*	Set the clock device (even if none loaded)
*
SETCLK	CALL	WRITECK		Write time to CK:
	ANA	A
	RET

* ==============================================
*
*	WRITECK - Write time to CK: device
*
* ==============================================
WRITECK	MVI	A,0		Channel 0
	LXI	D,DEFALT
	LXI	H,CKDVD		CK: device
	SCALL	.OPENW		Open for write
	RC

	LXI	H,HMSLC		'hh:mm:ss'
	LDA	MYHH		our copy of hours
	CALL	DTOBCD		Convert and store ASCII

	MVI	M,':'
	INX	H
	LDA	MYMM		our copy of minutes
	CALL	DTOBCD		Convert and store ASCII

	MVI	M,':'
	INX	H
	LDA	MYSS		our copy of seconds
	CALL	DTOBCD		Convert and store ASCII

	MVI	A,0		Console channel
	LXI	B,9		9 bytes
	LXI	D,HMSLC		'hh:mm:ss' (now current)
	SCALL	.WRITE		Write it
	RC

	MVI	A,0
	SCALL	.CLOSE
	RC

	CALL	$TYPTX
	DB	NL,'CLOCK SET TO: ',200Q

	LXI	H,HMSLC
	CALL	$TYPTX.

	MVI	A,0
	LXI	D,DEFALT
	LXI	H,CKDVD
	SCALL	.OPENR
	RC

	MVI	A,0		Console I/O
	LXI	B,9		9 bytes
	LXI	D,HMSUC		HH:MM:SS
	SCALL	.READ		Read it
	RC

	MVI	A,0
	SCALL	.CLOSE
	RC

	CALL	$TYPTX
	DB	NL,'CLOCK READS: ',200Q

	LXI	H,HMSUC
	SCALL	.PRINT
	ANA	A
	RET

* ==============================================
*
*	DTOBCD - convert decimal value into
*	two ASCII bytes, high nibble first, then
*	low.  Store these in (HL) while incrementing
*	location.
*
* ==============================================
DTOBCD	CALL	BTOBCD		Once for each nibble
BTOBCD	RRC			Rotate nibble
	RRC
	RRC
	RRC
	
	PUSH	PSW
	ANI	0FH		mask nibble
	ADI	'0'		Convert to ASCII
	MOV	M,A		Store it
	INX	H		and point to next
	POP	PSW

	RET

* ==============================================
*
*	WRRTC - Write time, date and DOW to the Real
*	time clock chip
*
*	EXIT:	'C' set if no RTC found
*
* ==============================================
WRRTC	CALL	CHKRTC		Do we have the chip?
	RC			no, return with 'C' set

	CALL	CSETUP		Set up the RTC chip
	CALL	WREADY		Make sure it's ready for I/O

	MVI	A,REFRST+REFSTOP+REF24
	OUT	CLOCK+REGF
	CALL	WREADY
*
*	Write time, date and DOW to the clock chip
*
	LDA	MYSS		get Seconds
	ANI	0FH		low nibble (ones)
	OUT	CLOCK+S1	send to RTC
	CALL	WREADY

	LDA	MYSS		get Seconds
	RRC			high nibble (tens)
	RRC
	RRC
	RRC
	ANI	0FH
	OUT	CLOCK+S10	send to RTC
	CALL	WREADY

	LDA	MYMM		get Minutes
	ANI	0FH		low nibble (ones)
	OUT	CLOCK+MI1	send to RTC
	CALL	WREADY

	LDA	MYMM		get Minutes
	RRC			high nibble (tens)
	RRC
	RRC
	RRC
	ANI	0FH
	OUT	CLOCK+MI10	send to RTC
	CALL	WREADY

	LDA	MYHH		Get Hours
	ANI	0FH		low nibble (ones)
	OUT	CLOCK+H1	send to RTC
	CALL	WREADY

	LDA	MYHH		Get Hours
	RRC			high nibble (tens)
	RRC
	RRC
	RRC
	ANI	0FH
	OUT	CLOCK+H10	send to RTC
	CALL	WREADY

	LDA	MYDD		Get Day
	ANI	0FH		low nibble (ones)
	OUT	CLOCK+D1	send to RTC
	CALL	WREADY

	LDA	MYDD		Get Day
	RRC			high ibble (tens)
	RRC
	RRC
	RRC
	ANI	0FH
	OUT	CLOCK+D10	send to RTC
	CALL	WREADY

	LDA	DOW		Get Day of Week
	ANI	0FH
	OUT	CLOCK+W		send to RTC
	CALL	WREADY

	LDA	MYMO		Get Month
	ANI	0FH		low nibble (ones)
	OUT	CLOCK+MO1	send to RTC
	CALL	WREADY

	LDA	MYMO		Get Month
	RRC			high nibble (tens)
	RRC
	RRC
	RRC
	ANI	0FH
	OUT	CLOCK+MO10	send to RTC
	CALL	WREADY

	LDA	MYYY		Get Year
	ANI	0FH		low nibble ones)
	OUT	CLOCK+Y1	send to RTC
	CALL	WREADY

	LDA	MYYY		get Year
	RRC			high nibble (tens)
	RRC
	RRC
	RRC
	ANI	0FH
	OUT	CLOCK+Y10	send to RTC

	CALL	WREADY
	CALL	CSETUP
	RET

* ==============================================
*
*	CHKRTC - Test for real time clock available
*
*	Returns:
*		'Z' if OK
*		'C' if no RTC
*
* ==============================================
CHKRTC	MVI	A,REF24		24 hour clock mode
	MOV	C,A
	OUT	CLOCK+REGF
	IN	CLOCK+REGF
	ANI	0FH
	CMP	C
	RZ

	CALL	$TYPTX
	DB	NL,'CHIPTST: NO RTC CHIP?',ENL
	STC
	RET

* ==============================================
*
*	CSETUP - set up clock register info
*
* ==============================================
CSETUP	MVI	A,REF24		24 hour clock mode
	MOV	C,A
	OUT	CLOCK+REGF
	MVI	A,RET1+REITR+REMASK
	MOV	C,A
	OUT	CLOCK+REGE
	MVI	A,RDIRQ
	OUT	CLOCK+REGD
	ANA	A
	RET

* ==============================================
*
*	WREADY - wait 'til clock is ready for next I/O
*
* ==============================================
WREADY	IN	CLOCK+REGD	Control reg D
	ORI	RDHOLD		HOLD bit
	OUT	CLOCK+REGD	set it
	IN	CLOCK+REGD	read control reg again
	ANI	RDBUSY		BUSY?
	RZ			no, done

	IN	CLOCK+REGD	Read control reg again
	ANI	0FFH-RDHOLD	!HOLD
	OUT	CLOCK+REGD	set it
	JMP	WREADY		retry...

* ==============================================
*
*	RDRTC - Read from the real time clock and
*	store year, month, day and day of week in
*	corresponding local variables.
*
*	EXIT:	'C' set if no RTC found
*
* ==============================================
RDRTC	CALL	CSETUP		Set up the clock chip
	RC			return with 'C' set if none

	CALL	RDYEAR		Read and store Year
	CALL	RDMONTH		Read and store Month
	CALL	RDDOW		Read and store Day of Week
	CALL	RDDAY		Read and store Day of Month
	CALL	RDHMS
	RET


RDTBAD	CALL	$TYPTX
	DB	'IN RDTIM1-2: ',200Q

BADDATA	CALL	$TYPTX
	DB	'RDDATA: READING BAD DATA FROM RTC AT 240Q ',ENL
	STC
	RET

*
*	RDYEAR - Read Year 10's then 1's 
*
RDYEAR	EQU	*
*
*	Read Year 10's position
*
RDY10	IN	CLOCK+Y10	Read Year 10's
	ANI	0FH
	MOV	B,A		save it
	IN	CLOCK+Y10	read again
	ANI	0FH
	CMP	B		same?
	JNZ	RDY10		repeat 'til not changing

	CPI	10		must be < 10
	JNC	BADDATA

	RRC			rotate to high bits
	RRC
	RRC
	RRC
	MOV	B,A		save it

*
*	Read Year 1's position
*
RDY1	IN	CLOCK+Y1	Read Year 1's
	ANI	0FH
	MOV	C,A		save it in C
	IN	CLOCK+Y1	read again
	ANI	0FH
	CMP	C		same?
	JNZ	RDY1		repeat 'til not changing

	CPI	10		must be < 10
	JNC	BADDATA

	ORA	B		A = YY
	STA	MYYY
	RET

*
*	RDMONTH - Read Month 10's and then 1's
*
RDMONTH	EQU	*
RDMO10	IN	CLOCK+MO10	Read Month 10's
	ANI	0FH
	MOV	B,A		save it
	IN	CLOCK+MO10	read again
	ANI	0FH
	CMP	B		same?
	JNZ	RDMO10		repeat 'til not changing

	CPI	2		Must be 0 or 1
	JNC	BADDATA

	RRC			rotate high bits
	RRC
	RRC
	RRC
	MOV	B,A		and save

*
*	Read month Ones
*
RDMO1	IN	CLOCK+MO1	Read Month 1's
	ANI	0FH
	MOV	C,A		save it
	IN	CLOCK+MO1	read again
	ANI	0FH
	CMP	C		same?
	JNZ	RDMO1		repeat 'til not changing

	CPI	10		Must be < 10
	JNC	BADDATA

	ORA	B		combine 10's and 1's
	CPI	13H		(typo? < 13 decimal not hex?)
	JNC	BADDATA

	CPI	0
	JZ	BADDATA		must be > 0

	STA	MYMO		Save it!
	RET

*
*	RDDAY - Read day (10's and 1's)
*
RDDAY	EQU	*
RDD10	IN	CLOCK+D10	Read Day 10's
	ANI	0FH
	MOV	B,A		save
	IN	CLOCK+D10	read again
	ANI	0FH
	CMP	B		same?
	JNZ	RDD10		repeat 'til not changing

	CPI	4		must be < 4
	JNC	BADDATA

	RRC			rotate to high bits
	RRC
	RRC
	RRC
	MOV	B,A		and save

*
*	Read Day one's
*
RDD1	IN	CLOCK+D1	Read day 1's
	ANI	0FH
	MOV	C,A		save
	IN	CLOCK+D1	read again
	ANI	0FH
	CMP	C		same?
	JNZ	RDD1		repeat 'til not changing

	CPI	10		must be < 10
	JNC	BADDATA

	ORA	B		Combine 10's and 1's
	CPI	32H		(typo? <32 decimal not hex?)
	JNC	BADDATA

	ANA	A		can't be zero either
	JZ	BADDATA

	STA	MYDD		Save it!
	RET

*
*	RDDOW - Read Day of the week
*
RDDOW	IN	CLOCK+W		Read DOW
	ANI	0FH
	MOV	C,A		save
	IN	CLOCK+W		read again
	ANI	0FH
	CMP	C		same?
	JNZ	RDDOW		repeat 'til not changing

	CPI	7		Must be 0-6
	JNC	BADDATA

	STA	DOW		save it!
	ANA	A
	RET

*
*	Read Hours, Minutes and Seconds
*
RDHMS	EQU	*
*
*	Read Hours 10's
*
RDH10	IN	CLOCK+H10	Read Hours 10's
	ANI	0FH
	MOV	B,A		save
	IN	CLOCK+H10	read again
	ANI	0FH
	CMP	B		same?
	JNZ	RDH10		repeat 'til not changing

	ANI	11111011B
	CPI	3 
	JNC	RDTBAD

	RLC			rotate to high bits
	RLC
	RLC
	RLC
	MOV	B,A		and save

*
*	Read Hours 1's
*
RDH1	IN	CLOCK+H1	Read hour ones digit
	ANI	0FH
	MOV	C,A		save
	IN	CLOCK+H1	read again
	ANI	0FH
	CMP	C		same?
	JNZ	RDH1		repeat 'til not changing

	CPI	10		must be < 10
	JNC	RDTBAD

	ORA	B		Get full hours value
	
	CPI	24H		(typo? should be < 24 decimal?)
	JNC	RDTBAD

	STA	MYHH		Save it!

*
*	Read Minutes
*
RDM10	IN	CLOCK+MI10	Read Minutes tens
	ANI	0FH
	MOV	B,A		save
	IN	CLOCK+MI10	read again
	ANI	0FH
	CMP	B		same?
	JNZ	RDM10		repeat 'til not changing

	CPI	7		must be 0-6
	JNC	BADDATA

	RLC			rotate to high nibble
	RLC
	RLC
	RLC
	MOV	B,A		save

*
*	Read Minutes (1's digit)
*
RDM1	IN	CLOCK+MI1	Read minute one's
	ANI	0FH
	MOV	C,A		save
	IN	CLOCK+MI1	read again
	ANI	0FH
	CMP	C		same?
	JNZ	RDM1		repeat 'til not changing

	CPI	10		must be < 10
	JNC	BADDATA

	ORA	B		combine 10's and 1's
	STA	MYMM		save it!

*
*	Read Seconds
*
RDS10	IN	CLOCK+S10	Read seconds 10's digit
	ANI	0FH
	MOV	B,A		save
	IN	CLOCK+S10	read again
	ANI	0FH
	CMP	B		same?
	JNZ	RDS10		repeat 'til not changing

	CPI	7		must be 0-6
	JNC	BADDATA

	RLC			move to high nibble
	RLC
	RLC
	RLC
	MOV	B,A		save

*
*	Read Seconds one digit
*
RDS1	IN	CLOCK+S1	Read seconds 1 digit
	ANI	0FH
	MOV	C,A		save
	IN	CLOCK+S1	read again
	ANI	0FH
	CMP	C		same?
	JNZ	RDS1		repeat 'til not changing

	CPI	10		must be < 10
	JNC	BADDATA

	ORA	B		Combine 10's and 1's
	STA	MYSS		save it!
	RET

* ==============================================
*
*	CODEDT - Convert Date to coded date (HDOS internal
*	format used in S.DATC
*
* ==============================================
CODEDT	LDA	MYYY		Year
	LXI	H,0		HL = 0
	CALL	BCDTOD		decimal

	CALL	$DADA.		(HL) = Year

	DAD	H		*2
	DAD	H		*4
	DAD	H		*8
	DAD	H		*16 (shift left 4 bits)

	LDA	MYMO		Month
	CALL	BCDTOD		decimal
	CALL	$DADA.		(HL) = Year <<4 + Month

	DAD	H		*2
	DAD	H		*4
	DAD	H		*8
	DAD	H		*16
	DAD	H		*32 (shift left 5 bits)

	LDA	MYDD		Day
	CALL	BCDTOD		decimal

	CALL	$DADA.		YYMMDD as decimal value
	RET

* ==============================================
*
*	BCDTOD - A has 10's digit in top nibble
*	and 1's digit in bottom nibble. Convert
*	to decimal
*
* ==============================================
BCDTOD	MOV	B,A		save the value
	ANI	0F0H		high nibble
	RRC			a/2
	MOV	C,A		save a/2
	RRC			a/4
	RRC			a/8
	ADD	C		a/8 + a/2
	MOV	C,A
	MOV	A,B
	ANI	0FH		; 15 
	ADD	C
	RET

* ==============================================
*
*	DOCMD - process option supplied on the
*	command line (e.g. HELP, SET, SETUP, etc.)
*
* ==============================================
DOCMD	CALL	SKIPWS		Skip blanks and tabs
	XTHL			(HL) = return address
*				Save HL on the stack

	PUSH	D		(DE) = command item
DOCMD1	LDAX	D		Fetch char from command
	CMP	M		match?
	JNZ	DOCMD2		No, fixup and continue...
*
*	So far we have a match, keep scanning
*
	INX	D		next char from command
	INX	H		next code byte
	XRA	A		NUL
	CMP	M		== NUL?
	JNZ	DOCMD1		no, keep going...
*
*	We have a match!
*
	INX	SP		fix the stack pointer
	INX	SP

	XTHL			(SP) = code block to execute
	LDAX	D
	ANA	A
	RET
*
*	No match yet

DOCMD2	POP	D		Undo PUSH D

DOCMD3	XRA	A		A=0
	CMP	M		== NUL?
	INX	H		next
	JNZ	DOCMD3		no, searching...

	XTHL
	LDAX	D
	ANA	A
	STC
	RET

* ==============================================
*
*	STRCPY - Copy string and null-terminate
*
*	Entry: 	C = string length
*		DE = destination
*		HL = source
*
* ==============================================
STRCPY	XRA	A		Zero
	CMP	C		Check for done?
	STAX	D		Store byte
	RZ			leave if done

	DCR	C		else, count down
	MOV	A,M		fetch byte
	STAX	D		store it
	INX	D		next destination
	INX	H		next source
	JMP	STRCPY		loop

* ==============================================
*
*	SKIPWS - Skip over white space (blanks
*	and tabs. (similar to $SOB)
*
*	ENTRY:	(DE) = string
*	EXIT:	(DE) updated
* ==============================================
SKIPW1	INX	D
SKIPWS	LDAX	D		A = (DE)
	CPI	' '		Blank?
	JZ	SKIPW1		Yes, next...

	CPI	TAB		or Tab?
	JZ	SKIPW1		Yes, next...
	RET

* ==============================================
*
*	Storage
*
* ==============================================
CKDVD	DB	'CK:',0
DEFALT	DB	0,0,0,0,0,0	Default block 

CMDLINE	EQU	*
*
*	Working space
*
MEMTOP	EQU	CMDLINE+101

	END	ENTRY