DREV EQU 24H ;	06/13/79  R. CURTISS	"," FOR DELIMITER ALSO

;DREV EQU 23H ;	06/10/79  R. CURTISS	DCLOSE XRA A, NOT IF READ

;DREV EQU 22H ;	08/19/78  R. CURTISS	DEF. DMA = 80 AFTER
;					READS AND WRITES
;DREV EQU 21H ;	08/19/78  R. CURTISS	GCLOSE ADDITIONS
;
;DREV EQU 20H ;	08/17/78  R. CURTISS	INITIAL CODING
;
;DREV EQU 15H ;	07/26/78  R. CURTISS	BWRITE - MVI A,0 JNZ
;
;DREV EQU 14H ;	07/25/78  R. CURTISS	OPEN- NR=0
;
;DREV EQU 13H ;	07/25/78  R. CURTISS	FIX ERROR IN READ
;					AND OTHER CHANGES
;
;DREV EQU 12H ;	07/01/78  R. CURTISS	FIX ERRORS
;
;DREV EQU 11H ;	07/01/78  R. CURTISS	INITIAL CODING
;
; CP/M DISK I/O PACKAGE
;	1. INITIAL IMPLEMENTATION
;	  OPEN, CLOSE, READ BYTE, WRITE BYTE
;
;	2. NEXT STAGE OF DEVELOPMENT
;	  READ LINE, WRITE LINE, GENERAL CLOSE
;
;	3. ALLOW THE FOLLOWING FOR FILE NAMES:
;		CON:  - CONSOLE  IN/OUT
;		RDR:  - READER   IN
;		PUN:  - PUNCH       OUT
;		LST:  - LISTING     OUT
;
;
; TO OPEN DISK FILE
;	ERROR IF FILE ALREADY OPEN
;	ERROR IF BAD FILE NAME
;	SELECT ( ACCESS )
;	   ( 1 = READ ) CONTINUE
;	   ( 3 = WRITE )
;		ACCESS = 2
;		DELETE FILE IF PRESENT
;		CREATE FILE
;		ERROR IF NO DIRECTORY SPACE
;		FIN
;	   ( 2 = WRITE )
;		ERROR IF FILE IS PRESENT
;		CREATE FILE
;		ERROR IF NO DIRECTORY SPACE
;		FIN
;	   ( OTHER ) ERROR  ILLEGAL ACCESS CODE
;	   FIN
;	OPEN FILE
;	ERROR IF NOT PRESENT
;	STATUS = 0   NORMAL
;	POINTER = 0    BUFFER EMPTY
;	FIN
;
;  INPUTS:
;    (HL) POINTS TO FILE TABLE ORIGIN
;    (DE) POINTS TO FILE NAME STRING
;    (BC) POINTS TO ACCESS CODE
;
;  OUTPUTS:
;    (A)=(HL)= OPERATION STATUS
;    (Z)     = CONDITION OF (A)
;
;
FCBOFF	EQU	4	; FCB OFFSET IN FILE TABLE
BUFF	EQU	37	; BUFFER OFFSET IN FILE TABLE
BDOS	EQU	0005H	; ENTRY POINT TO OPERATING SYSTEM
 

	DB	DREV	; PUT REVISION NUMBER IN CODE


DOPEN:	SHLD	FTABLE	; SAVE FILE TABLE POINTER

	MOV	A,M	; GET ACCESS CODE FROM FILE TABLE
	CPI	0
	JNZ	ERR	; JUMP IF FILE ALREADY OPEN

	LDAX	B	; GET OPEN ACCESS CODE
	STA	ACCESS

	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	LXI	B,FCBOFF  ; FCB OFFSET IN FILE TABLE
	DAD	B
	CALL	GETNAM	; GET FILE NAME
	JNZ	ERR	; JUMP IF NAME ERROR

	LDA	ACCESS
	DCR	A
	JZ	OPEN6	; JUMP IF READ ACCESS DESIRED

	CPI	2
	JNZ	OPEN2	; JUMP IF NOT WRITE WITH DELETE

	STA	ACCESS	; ACCESS = 2

	MVI	C,19
	CALL	BDOS1	; DELETE FILE IF PRESENT

	JMP	OPEN4

OPEN2:	CPI	1
	JNZ	ERR	; JUMP IF INVALID ACCESS CODE

	MVI	C,17
	CALL	BDOS1	; CHECK TO SEE IF FILE IS PRESENT
	CPI	255
	JNZ	ERR	; JUMP IF FILE IS PRESENT

OPEN4:	MVI	C,22
	CALL	BDOS1	; CREATE FILE
	CPI	255
	JZ	ERR	; JUMP IF NO DIRECTORY SPACE

OPEN6:	MVI	C,15
	CALL	BDOS1	; OPEN FILE
	CPI	255
	JZ	ERR	; JUMP IF NOT PRESENT

	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	LXI	D,FCBOFF+32
	DAD	D
	MVI	M,0	; NEXT RECORD NUMBER IN FCB
 
	CALL	GCLADD	; ADD FILE TABLE TO OPEN LIST

	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	LDA	ACCESS
	MOV	M,A	; SET ACCESS CODE IN FILE TABLE

	INX	H
	XRA	A
	MOV	M,A	; SET STATUS TO ZERO (NORMAL)

	INX	H
	MOV	M,A	; SET BUFFER POINTER TO ZERO

	JMP	RETURN
;
;
; TO CLOSE FILE
;	OUTPUT LAST BUFFER IF OPEN FOR WRITE
;	ERROR IF ACCESS < 1 OR > 2
;	CLOSE FILE IF OPEN FOR WRITE
;	ERROR IF NOT PRESENT
;	ACCESS = 0
;	BUFFER POINTER = 0
;	FIN
;
;  INPUT:
;    (HL) POINTS TO FILE TABLE ORIGIN
;
;  OUTPUTS:
;    (A)=(HL)= OPERATION STATUS
;    (Z)     = CONDITION OF (A)
;
DCLOSE:	SHLD	FTABLE	; SAVE FILE TABLE POINTER

	MOV	A,M	; GET ACCESS CODE FROM FILE TABLE
	CPI	2
	JNZ	CLOSE1	; JUMP IF NOT OPEN FOR WRITE

	CALL	CLOSE4	; OUTPUT LAST BUFFER IF NOT EMPTY
	JZ	CLOSE2	; JUMP IF NO WRITE ERROR

	PUSH	PSW	; SAVE ERROR CONDITION
	CALL	CLOSE2	; CLOSE THE FILE
	POP	PSW
	JMP	ERR

CLOSE1:	ORA	A
	JZ	RETURN	; JUMP IF ALREADY CLOSED

	CPI	1
	JNZ	ERR	; JUMP IF INVALID ACCESS CODE

CLOSE2:	CALL	GCLREM	; REMOVE FILE TABLE FROM OPEN LIST

	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	XRA	A
	MOV	C,M	; GET ACCESS CODE
	MOV	M,A	; ACCESS = 0 - FILE NOT OPEN

	INX	H
	MOV	M,A	; STATUS = 0 - NORMAL

	INX	H
	MOV	M,A	; BUFFER POINTER = 0

	DCR	C
	JZ	RETURN	; JUMP IF OPEN FOR READ

	MVI	C,16
	CALL	BDOS1	; CLOSE FILE
	CPI	255
	JZ	ERR	; JUMP IF FILE NOT PRESENT

	XRA	A	; NO ERROR
	JMP	RETURN

CLOSE4:	INX	H
	INX	H
	MOV	A,M	; GET BUFFER POINTER
	ANI	7FH	; MSB SHOULD BE 0 BUT BE SAFE
	RZ		; RETURN IF BUFFER IS EMPTY (Z)=1

	LXI	D,BUFF+127-2  ; -2 FOR 2 (INX HL) ABOVE
	DAD	D	; (HL) POINTS TO LAST BUFFER BYTE
	CMA
	ADI	128+1	; PAD COUNT = 128 - POINTER

CLOSE6:	MVI	M,1AH	; PAD BUFFER WITH CONTROL Z
	DCX	H
	DCR	A
	JNZ	CLOSE6

	CALL	WRITE2	; OUTPUT LAST BUFFER
	RET		; (Z)=1 IF WRITE IS OK
;
;
; TO CLOSE ALL OPEN FILES
;	FOR EACH OPEN FILE
;	    CLOSE FILE
;	    FIN
;	FIN
;
;  INPUTS:
;	NONE
;
;  OUTPUTS:
;	(A)=(HL)= OPERATION STATUS
;	(Z)     = CONDITION OF (A)
;
GCLOSE:	LDA	LSIZE	; RECALL OPEN FILE COUNT
	ORA	A
	RZ		; RETURN IF LIST IS EMPTY

	LXI	H,FLIST	; GET FIRST FILLE TABLE POINTER
	MOV	E,M
	INX	H
	MOV	D,M
	XCHG
	CALL	DCLOSE	; CLOSE AND DELETE FILE FROM LIST
	JMP	GCLOSE
;
;
;	ADD FILE TABLE TO OPEN FILE LIST
;
GCLADD:	LDA	LSIZE	; GET OPEN FILE COUNT
	CPI	LMAX	; FILE LIST MAX SIZE
	JNC	GCLA9	; JUMP IF LIST IS FULL

	INR	A
	STA	LSIZE	; LSIZE = LSIZE + 1
	DCR	A
	ADD	A	; A = A*2
	MOV	E,A
	MVI	D,0
	LXI	H,FLIST
	DAD	D	; (HL) POINTS TO NEXT LIST ENTRY POS.

	XCHG
	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	XCHG

	MOV	M,E
	INX	H
	MOV	M,D	; LIST(LSIZE) = FILE TABLE POINTER
	RET

GCLA9:	; ****************** NEED EROR MESSAGE
	RET
;
;
;	REMOVE FILE TABLE POINTER FROM OPEN FILE LIST
;
GCLREM:	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	XCHG
	LXI	H,FLIST	; ORIGIN OF OPEN FILE LIST
	LDA	LSIZE	; RECALL OPEN FILE COUNT
	MOV	C,A
	INR	C

GCLR1:	DCR	C
	JZ	GCLR9	; JUMP IF END OF OPEN FILE LIST

	MOV	A,M
	INX	H
	XRA	E
	MOV	B,A

	MOV	A,M
	INX	H
	XRA	D
	ORA	B
	JNZ	GCLR1	; JUMP IF NO MATCH

	MOV	D,H
	MOV	E,L
	DCX	D
	DCX	D

GCLR2:	DCR	C
	JZ	GCLR8	; JUMP IF END OF LIST

	MOV	A,M
	STAX	D
	INX	H
	INX	D
	MOV	A,M
	STAX	D	; LIST(M-1) = LIST(M)
	INX	H
	INX	D	; M = M + 1
	JMP	GCLR2

GCLR8:	LDA	LSIZE
	DCR	A
	STA	LSIZE
	RET

GCLR9:	; ****************** NEED ERROR MESSAGE
	RET
;
;
; TO READ A LINE
;	ERROR IF ACCESS <> "READ"
;	ERROR IF STATUS <> "NORMAL"
;	I = 1
;	GET-NEXT-BYTE
;	UNTIL ( EOL,EOF,ERR )
;	    IF ( I <= MAX-CHARACTER-COUNT )
;		LINE(I) = BYTE
;		I = I + 1
;		FIN
;	    GET-NEXT-BYTE
;	    FIN
;	RETURN-ACTUAL-CHARACTER-COUNT
;	FIN
;
;  INPUTS:
;	(HL) POINTS TO FILE TABLE
;	(DE) POINTS TO LINE BUFFER ORIGIN
;	(BC) POINTS TO PARAMETER LIST
;		3RD  POINTS TO MAX CHARACTER COUNT (255 MAX)
;		4TH  POINTS TO ACTUAL CHARACTER COUNT (255 MAX)
;
;  OUTPUTS:
;	(A)=(HL)= OPERATION STATUS
;	(Z)     = CONDITION OF (A)
;
LREAD:	SHLD	FTABLE	; SAVE FILE TABLE POINTER
	XCHG
	SHLD	LPOINT	; SAVE LINE POINTER

	LXI	H,DBYTE
	SHLD	DATA	; DATA RETURN POINTER

	MOV	H,B
	MOV	L,C

	MOV	E,M
	INX	H
	MOV	D,M	; (DE) POINTS TO 3RD ARG

	XCHG
	MOV	C,M	; (C) HOLDS MAX LINE LENGTH
	MOV	A,C
	STA	CMAX	; SAVE MAX LINE LENGTH
	XCHG

	INX	H
	MOV	E,M
	INX	H
	MOV	D,M	; (DE) POINTS TO 4TH ARG

	XCHG
	SHLD	ACTP	; SAVE POINTER FOR ACTUAL LENGTH

	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	MOV	A,M	; GET ACCESS CODE
	CPI	1
	JNZ	ERR	; JUMP IF NOT OPEN FOR READ

	INX	H
	MOV	A,M	; GET STATUS CODE
	ORA	A
	JNZ	ERR	; JUMP IF NOT NORMAL

	INX	H	; (HL) POINTS TO BUFFER POINTER
	SHLD	BPOINT	; SAVE IT

LREAD1:	CALL	LREAD5	; GET NEXT BYTE FROM DISK
	JNZ	LREAD2	; JUMP IF EOL,EOF,ERR

	CALL	LREAD8	; STORE BYTE INTO LINE
	JMP	LREAD1

LREAD2:	PUSH	PSW	; SAVE READ STATUS
	LDA	CMAX	; RECALL MAX CHARACTER COUNT
	SUB	C
	LHLD	ACTP
	MOV	M,A	; RETURN ACTUAL CHARACTER COUNT
	POP	PSW

	CPI	0DH	; CARRIAGE RETURN
	JNZ	RETURN	; RETURN IF EOF OR ERR

	XRA	A
	JMP	RETURN	; NORMAL RETURN
;
;	GET NEXT BYTE
;
LREAD5:	LHLD	BPOINT	; RECALL BUFFER POINTER POINTER
	PUSH	B	; SAVE LINE SPACE COUNT
	CALL	BRXXX	; GET NEXT BYTE FROM DISK
	POP	B
	RNZ		; RETURN IF EOF,ERR

	LDA	DBYTE	; GET BYTE JUST READ
	ANI	7FH
	JZ	LREAD5	; IGNORE NULL

	CPI	0AH
	JZ	LREAD5	; IGNORE LINE FEED

	CPI	7FH
	JZ	LREAD5	; IGNORE RUBBOUT

	CPI	1AH	; CONTROL Z
	JZ	LREAD6	; JUMP IF END OF FILE

	CPI	0DH
	JZ	LREAD7	; JUMP IF CARRIAGE RETURN

	CMP	A	; (Z)=1
	RET		; NORMAL RETURN

LREAD6:	MVI	A,255	; END OF FILE

LREAD7:	ORA	A	; END OF LINE
	RET
;
;	STORE NEXT BYTE IN LINE
;
LREAD8:	INR	C
	DCR	C
	RZ		; RETURN IF LINE BUFFER FULL

	LHLD	LPOINT	; RECALL LINE BUFFER POINTER
	MOV	M,A
	INX	H
	SHLD	LPOINT
	DCR	C
	RET
;
;
; TO READ BYTE
;	ERROR IF ACCESS <> "READ"
;	ERROR IF STATUS <> "ZERO"
;	IF ( BUFFER EMPTY )
;	   GET NEXT BUFFER LOAD
;	   POINT = 0
;	   RETURN IF "EOF"
;	   FIN
;	GET NEXT BYTE FROM BUFFER
;	POINT = POINT + 1
;	FIN
;
;  INPUTS:
;    (HL) POINTS TO FILE TABLE ORIGIN
;    (DE) POINTS TO DATA BYTE STORAGE
;
;  OUTPUTS:
;    (A)=(HL)= OPERATION STATUS
;    (Z)     = CONDITION OF (A)
;    ((DE))  = DATA BYTE RETURNED
;
BREAD:	SHLD	FTABLE	; SAVE FILE TABLE POINTER
	XCHG
	SHLD	DATA	; SAVE DATABYTE POINTER
	MVI	M,1AH	; TENTATIVELY RETURN CONTROL Z

	XCHG
	MOV	A,M	; GET ACCESS CODE
	CPI	1
	JNZ	ERR	; JUMP IF NOT READ ACCESS

	INX	H
	MOV	A,M	; GET STATUS CODE
	CPI	0
	JNZ	ERR	; JUMP IF NOT NORMAL

	INX	H

BRXXX:	MOV	A,M	; GET BUFFER POINTER
	MOV	E,A	; SAVE CURRENT POINTER
	INR	A
	ANI	7FH
	MOV	M,A	; POINTER = (POINTER + 1) MOD 128

	MOV	A,E	; GET CURRENT POINTER
	ORA	A
	JNZ	READ2	; JUMP IF BUFFER NOT EMPTY

	CALL	READ4	; GET NEXT BUFFER LOAD
	JNZ	ERR	; JUMP IF READ ERROR

	ORA	A
	JNZ	RETURN	; JUMP IF END OF FILE

	MVI	E,0	; CURRENT POINTER

READ2:	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	MVI	D,0	; (E) IS BUFFER POINTER
	DAD	D
	LXI	D,BUFF	; BUFFER OFFSET IN FILE TABLE
	DAD	D	; (HL) POINTS TO NEXT BYTE IN BUFFER

	MOV	A,M	; GET NEXT DATA BYTE
	LHLD	DATA	; RECALL DATA RETURN POINTER
	MOV	M,A	; RETURN DATA BYTE TO CALLER

	XRA	A	; (A)=0   (Z)=1
	JMP	RETURN	; NORMAL RETURN


READ4:	MVI	C,26
	CALL	BDOS2	; SET DMA ADDRESS

	MVI	C,20
	CALL	BDOS1	; READ NEXT DISK RECORD

	PUSH	PSW
	MVI	C,26
	LXI	D,80H
	CALL	BDOS	; RESTORE DMA ADDR TO DEFAULT
	POP	PSW

	ORA	A
	RZ		; RETURN IF OK  (Z)=1

	CPI	1	; EOF
	RNZ		; RETURN IF ERROR (A)>1  (Z)=0

	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	INX	H
	MVI	A,255
	MOV	M,A	; SET STATUS TO "EOF"

	CPI	255	; EOF  (A)=255  (Z)=1
	RET		; END OF FILE DETECTED
;
;
; TO WRITE A LINE
;	ERROR IF ACCESS <> "WRITE"
;	ERROR IF STATUS <> "ZERO" "NORMAL"
;	FOR I = 1 TO LENGTH OF LINE
;	    WRITE BYTE LINE(I)
;	    FIN
;	FIN
;
;  INPUTS:
;	(HL) POINTS TO FILE TABLE
;	(DE) POINTS TO LINE BUFFER ORIGIN
;	(BC) POINTS TO LINE LENGTH IN BYTES (255 MAX)
;
;  OUTPUTS:
;	(A)=(HL)= OPERATION STATUS
;	(Z)     = CONDITION OF (A)
;
LWRITE:	SHLD	FTABLE	; SAVE FILE TABLE POINTER

	MOV	A,M	; GET ACCESS CODE
	CPI	2
	JNZ	ERR	; JUMP IF NOT OPEN FOR WRITE

	INX	H
	MOV	A,M	; GET STATUS CODE
	ORA	A
	JNZ	ERR	; JUMP IF NOT NORMAL

	INX	H	; POINTS TO BUFFER POINTER

	LDAX	B	; CHARACTER COUNT
	MOV	C,A
	INR	C

LWRIT1:	DCR	C
	JZ	LWRIT2	; JUMP IF END OF LINE

	PUSH	H
	PUSH	D
	PUSH	B
	LDAX	D	; GET NEXT DATA BYTE
	MOV	B,A
	CALL	BWXXX	; WRITE BYTE TO DISK
	POP	B
	POP	D
	POP	H
	RNZ		; RETURN IF WRITE ERROR

	INX	D
	JMP	LWRIT1

LWRIT2:	MVI	B,0DH
	PUSH	H
	CALL	BWXXX	; WRITE CARRIAGE RETURN TO DISK
	POP	H
	RNZ		; RETURN IF WRITE ERROR

	MVI	B,0AH
	CALL	BWXXX	; WRITE LINE FEED TO DISK
	RET
;
;
; TO WRITE BYTE
;	ERROR IF ACCESS <> "WRITE"
;	ERROR IF STATUS <> "ZERO"
;	PUT BYTE INTO BUFFER
;	POINT = POINT + 1
;	IF ( BUFFER FULL )
;	   WRITE NEXT BUFFER LOAD
;	   POINT = 0
;	   FIN
;	FIN
;
;  INPUTS:
;    (HL) POINTS TO FILE TABLE ORIGIN
;    (DE) POINTS TO DATA BYTE STORAGE
;
;  OUTPUTS:
;    (A)=(HL)= OPERATION STATUS
;    (Z)     = CONDITION OF (A)
;
BWRITE:	SHLD	FTABLE	; SAVE FILE TABLE POINTER
	LDAX	D	; GET DATA BYTE
	MOV	B,A	; SAVE IN B

	MOV	A,M	; GET ACCESS CODE
	CPI	2
	JNZ	ERR	; JUMP IF NOT WRITE ACCESS

	INX	H
	MOV	A,M	; GET STATUS CODE
	CPI	0
	JNZ	ERR	; JUMP IF NOT NORMAL

	INX	H
;
;		(HL) POINTS TO BUFFER POINTER
;		(B)  DATA BYTE FOR OUTPUT
;
BWXXX:	MOV	A,M	; GET BUFFER POINTER
	MOV	E,A	; SAVE CURRENT POINTER
	INR	A
	ANI	7FH
	MOV	M,A	; POINTER = (POINTER+1) MOD 128

	MVI	D,0
	DAD	D
	LXI	D,BUFF-2  ; -2 FOR 2 (INX HL) ABOVE
	DAD	D	; (HL) = FTABLE+BUFF+POINT
	MOV	M,B	; STORE DATA BYTE INTO BUFFER

	CPI	0
	MVI	A,0	; NO ERROR
	JNZ	RETURN	; JUMP IF BUFFER NOT FULL

	CALL	WRITE2	; WRITE BUFFER TO DISK
	JNZ	ERR	; JUMP IF WRITE ERROR

	JMP	RETURN


WRITE2:	MVI	C,26
	CALL	BDOS2	; SET DMA ADDRESS

	MVI	C,21
	CALL	BDOS1	; WRITE NEXT DISK RECORD

	PUSH	PSW
	MVI	C,26
	LXI	D,80H
	CALL	BDOS	; RESTORE DMA ADDR. TO DEFAULT
	POP	PSW

	ORA	A
	RZ		; RETURN IF WRITE OK (A)=0  (Z)=1

	CPI	2	; END OF DISK
	RNZ		; RETURN IF ERROR (A)=1,>2  (Z)=0

	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	INX	H
	MVI	A,255	; END OF MEDIUM
	MOV	M,A	; SET STATUS

	CPI	255	; SET ZERO FLAG FOR NO ERROR
	RET		; (A)=255  (Z)=1
;
;
; SCAN FILE NAME
;  INPUTS:
;	(HL) POINTS TO FCB
;	(DE) POINTS TO FILE NAME - LEADING SPACES OK
;
;  OUTPUTS:
;	(A) = COUNT OF "?" IN NAME
;	(Z) = CONDITION OF (A)
;	(DE)= POINTER TO END OF NAME DELIMITER
;
GETNAM:			; GET FILE REFERENCE
	PUSH	H
	CALL	LL35	; IGNOR LEADING BLANKS
	ORA	A	; NULL INDICATES END OF BUFFER
	JZ	LLA6A	; JUMP IF NULL
 
	SBI	'@'	; CHECK IF DRIVE SPECIFIED
	MOV	B,A
	INX	D
	LDAX	D
	CPI	':'
	JZ	LL76
 
	DCX	D
	MVI	M,0	; ZERO FOR CURRENT DRIVE
	JMP	LL7C
LL76:
	MOV	M,B	; SPECIFIED DRIVE
	INX	D
LL7C:			; GET FILENAME
	MVI	B,8
	CALL	LL7E	; SCAN FILE NAME

	MVI	B,3
	CPI	'.'	; FILE TYPE DELIMITER
	JNZ	LLCF	; JUMP IF NO FILE TYPE

	INX	D
	CALL	LL7E	; SCAN FILE TYPE
	JMP	LLD6

LLCF:			; FILL REST OF FILE TYPE WITH SPACES
	INX	H
	MVI	M,' '
	DCR	B
	JNZ	LLCF
LLD6:			; PUT THREE ZEROS IN FILE CONTROL BLOCK
	MVI	B,3
LLD8:
	INX	H
	MVI	M,0
	DCR	B
	JNZ	LLD8
	POP	H
	LXI	B,000BH
LLE7:			; CHECK FOR AMBIGUOUS FILE REFERENCE
	INX	H
	MOV	A,M
	CPI	'?'
	JNZ	LLEF
	INR	B
LLEF:
	DCR	C
	JNZ	LLE7
	MOV	A,B
	ORA	A	; (A) IS COUNT OF '?' IN NAME
	RET		; (Z)=1 IF UNAMBIGUOUS NAME
;
;
; ---------------------
;
;	(B)= MAX CHARACTER COUNT
;
LL7E:			; SCAN FNAME OR FTYPE
	CALL	LL16
	JZ	LL9F	; JUMP IF DELIMITER FOUND
	INX	H
	CPI	'*'	; IF '*', FILL REST OF FILENAME WITH '?'
	JNZ	LL8F
	MVI	M,'?'
	JMP	LL91
LL8F:
	MOV	M,A	; STORE IN FCB
	INX	D
LL91:
	DCR	B	; CHARACTER COUNT
	JNZ	LL7E
LL95:			; IGNORE EXTRA CHARACTERS
	CALL	LL16
	JZ	LLA6
	INX	D
	JMP	LL95
LL9F:			; FILL REST OF FILENAME WITH SPACES
	INX	H
	MVI	M,' '
	DCR	B
	JNZ	LL9F
LLA6:
	RET
;
; ----------------------
;
LLA6A:
	POP	H
	ORI	255	; NO FILE NAME FOUND
	RET		; (Z)=0
;
; --------------------------
;
LL16:			; CHECK FOR DELIMITERS
	LDAX	D
	ORA	A	; NULL
	RZ
	CPI	' '	; SPACE
	JNC	LL16A	; JUMP IF NOT CONTROL CHARACTER
	MVI	A,'?'	; REPLACE CONTROL CHAR
	RET		; (Z)=0
LL16A:
	RZ
	CPI	'='
	RZ
	CPI	5FH	; BACK ARROW
	RZ
	CPI	'.'
	RZ
	CPI	','
	RZ
	CPI	':'
	RZ
	CPI	';'
	RZ
	CPI	'<'
	RZ
	CPI	'>'
	RET
;
;	----------------
;
LL35:			; ADVANCE  TO FIRST NON-BLANK OR END
	LDAX	D
	ORA	A
	RZ
	CPI	' '
	RNZ
	INX	D
	JMP	LL35
;
;
;
; BDOS FUNCTIONS USING FILE CONTROL BLOCK POINTER
;
BDOS1:	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	LXI	D,FCBOFF
	DAD	D
	XCHG		; (DE) POINTS TO FILE CONTROL BLOCK
	CALL	BDOS
	RET
;
;
; BDOS FUNCTIONS USING BUFFER POINTER
;
BDOS2:	LHLD	FTABLE	; RECALL FILE TABLE POINTER
	LXI	D,BUFF	; BUFFER OFFSET
	DAD	D
	XCHG		; (DE) POINTS TO BUFFER ORIGIN
	CALL	BDOS
	RET
;
;
; ALL ERROR CONDITIONS EXIT HERE
;
ERR:	LHLD	FTABLE	; RECALL FILE TABLE POINTER
;	....	.....	ADD ERROR MESSAGE SOMETIME
	INX	H
	MVI	A,255
	MOV	M,A	; SET STATUS TO EOF
	DCR	A	; (A) = 254  (UNSPECIFIED ERROR)
;
;
RETURN:	MVI	H,0
	MOV	L,A	; FORTRAN INTEGER FUNCTION RESULT
	ORA	A	; DETERMINE ZERO FLAG
	RET
;
;
; LOCAL TEMPORARY STORAGE
;
FTABLE:	DS	2	; FILE TABLE POINTER

ACCESS:	DS	1	; ACCESS CODE

DATA:	DS	2	; DATA BYTE POINTER

;
;
; STORAGE FOR OPEN FILE LIST
;
LSIZE:	DB	0	; COUNT OF FLIST SIZE
LMAX	EQU	10	; MAX SIZE OF OPEN FILE TABLE
FLIST:	DS	LMAX*2	; LIST OF FILE TABLE POINTERS
;
;
; STORAGE FOR LREAD
;
LPOINT:	DS	2
BPOINT:	DS	2
ACTP:	DS	2
DBYTE:	DS	1
CMAX:	DS	1
;
;