TITLE	'XMODEM/ASM'
;
;	Modem/Xmodem protocol for interchange of programs
;	with the CP/M operating system. Employs the
;	"Christensen" protocol.
;
;	Note entry into the routine is direct from the
;	terminal mode. The program prompts for the
;	filename to send/receive.
;
;	This segment makes no attempt to translate or
;	otherwise adjust the outgoing (or incoming) data
;	for the target/source system format. The user is
;	responsible for seeing to it that the data is
;	in the correct format for the transfer.
;
;	Comment (Copyright notice)
	COMM	'XMODEM 6.2.0 Authored by HAL N. FUQUAY.'
	COMM	'  Released to the public domain 01/17/1985'
;
SOH	EQU	1
EOT	EQU	4
ACK	EQU	6
NAK	EQU	21
CAN	EQU	24
;
;
SECWT	EQU	20		; 20 SECONDS FOR TIMEOUT
;
;
;	Called subroutines:
;	Getchar		- Called to check on input
;			from the Rs-232 interface.
;	Send		- Called to send a character to
;			to other end.
;
;	Note that CP/M sends in 128-byte blocks, which
;	means that it is 2-for-1 on the TRS-80.
;	Due to this difference in record lengths, the
;	system treats the file(s) to send/receive as
;	a byte-stream of data. 1 record is buffered
;	by the segment (128 bytes). The last block is
;	padded with zeros if padding is needed.
;
;
;	Entry points:
;	SENDCPM	-	Send a file to another MODEM
;			system.
;	RECVCPM	- 	Receives a file from a MODEM
;			system.
;
	ORG	3000H		; THE STARTING POINT
;
;
DUMMY	DEFL    DUMMY-$
	IF	NOT,DUMMY
	GET	SVC/ASM
	ENDIF
;
SENDXY
;
;	ENTER HERE TO SEND A XMODEM FILE. (HL) MUST
;	CONTAIN THE FILESPEC TO SEND.
;
	LD	A,@FSPEC
	LD	DE,CPMDCB
	RST	28H		; PARSE FILENAME
	JP	NZ,CERROR	; FATAL ERROR IN FILENAME
	LD	A,@FLAGS
	RST	28H
	SET	0,(IY+18)	; READ-ONLY
	LD	A,@OPEN		; OPEN THE FILE
	LD	DE,CPMDCB
	LD	HL,CPMBUF
	LD	B,0		; DO IT IN ANY CASE
	RST	28H		; OK -- IT IS OPEN!
	JP	NZ,CERROR	; OH OH -- SOMETHING IS
				; WRONG!
	LD	A,@GET
	LD	DE,CPMDCB
	RST	28H		; ATTEMPT TO READ 1 CHAR
	JP	NZ,CERROR	; SOMETHING IS WRONG
	LD	A,@REW
	LD	DE,CPMDCB
	RST	28H		; REWIND IF OK
	CALL	WAIT5		; WAIT 5 SECONDS
	CALL	SETOFF
	LD	HL,STSMES
	LD	A,@DSPLY
	RST	28H
	CALL	FLUSHBF		; FLUSH BUFFER
WAIT10	CALL	GETCHAR		; WAIT FOR A NAK
	CP	NAK		; SAME?
	JR	Z,OKSND
	CP	CAN		; CANCEL?
	JP	Z,CANCPM
	LD	A,@KBD
	RST	28H
	CP	80H
	JP	Z,CANCPM	; CANCEL IF <BREAK>
	JR	WAIT10
OKSND	LD	A,1
	LD	(BLOCK),A
	XOR	A
	LD	(LASTB),A
FILL1	LD	HL,XMTBUF	; TRANSMIT BUFFER
	LD	DE,XMTBUF+1
	LD	A,0
	LD	(HL),A
	LD	BC,127
	LDIR			; ZERO IT
	XOR	A
	LD	(CPMRET),A
	LD	B,128
	LD	HL,XMTBUF
FILDC	LD	DE,CPMDCB
	LD	A,@GET
	RST	28H		; GET 1 CHARACTER
	JP	NZ,DONXM
	LD	(HL),A
	INC	HL
	DJNZ	FILDC
SENDC	CALL	SENDBFR		; SEND A BUFFER UNTIL OK
	LD	A,(LASTB)
	OR	A
	JP	NZ,ENDXMT
	JR	FILL1
SENDBFR	LD	A,SOH		; SEND SOH

	CALL	SEND		; SEND IT
	LD	A,(BLOCK)
	CALL	SEND		; SEND BLOCK NUMBER
	LD	A,(BLOCK)	; RELOAD IT
	CPL			; COMPLEMENT ACCUM
	CALL	SEND		; CHECK OF BLOCK NUMBER
	LD	E,0		; STORE CHECKSUM
	LD	B,128		; HOW MANY TO DO
	LD	HL,XMTBUF	; PLACE TO GET FROM
SDCPM1	LD	A,(HL)
	ADD	A,E
	LD	E,A
	LD	A,(HL)		; RELOAD
	PUSH	DE
	PUSH	BC
	CALL	SEND		; SEND IT
	POP	BC		; RESTORE REGS
	POP	DE
	INC	HL
	DJNZ	SDCPM1		; CONTINUE
	LD	A,E
	CALL	SEND		; SEND CHECKSUM
	LD	B,SECWT		; USE THIS FOR SECONDS
WTOK	PUSH	BC		; SAVE COUNT
	CALL	GETFROM		; GET ONE CHARACTER WITH
				; TIMOUT
	JR	Z,NOERX		; CHECK THE ONE WE GOT
	POP	BC		; RESTORE COUNT
	DJNZ	WTOK
	JP	PERMER		; WE HAVE A PROBLEM
NOERX	POP	BC		; FIX STACK
	CP	CAN		; DO WE CANCEL?
	JP	Z,CCCPM		; CANCEL XMIT
	CP	ACK		; IS IT OK?
	JR	NZ,CHKRET	; RETRIES IF NOT
	LD	A,(BLOCK)	; ELSE NEXT BLOCK
	INC	A
	LD	(BLOCK),A
	XOR	A		; SET ZERO FLAG
	RET
CHKRET	LD	A,(CPMRET)
	INC	A		; INCREMENT IT
	CP	10		; IS IT 10?
	JR	Z,TOMRET	; PERMANENT ERROR
	LD	(CPMRET),A
	JR	SENDBFR
TOMRET	LD	HL,TOMER
	LD	A,@DSPLY
	RST	28H
	JP	CANCPM
TOMER	DM	'! Cannot send block -- abort !',13
CCCPM	LD	HL,CCPM
	LD	A,@DSPLY
	RST	28H
PERMER	LD	HL,PERM
	LD	A,@DSPLY
	RST	28H
	JP	CANCPM		; CANCEL FILESEND
CCPM	DM	'! Transmission cancelled by receiving end !',13
PERM	DM	10,'! Timeout waiting for ACK/NAK !',13
STSMES	DM	'! Waiting for initial NAK -- ^X to cancel !',13
GETFROM	CALL	GETCHAR		; CHECK FOR ONE NOW
	RET	Z		; RETURN IF SO
	PUSH	BC
	LD	A,@PAUSE
	LD	BC,32767
	RST	28H		; WAIT 1/2 SEC.
	POP	BC
	CALL	GETCHAR
	RET	Z
	PUSH	BC
	LD	A,@PAUSE
	LD	BC,32767
	RST	28H
	POP	BC
	CALL	GETCHAR
	RET			; RETURN ANYWAYS!
FLUSHBF	CALL	GETFROM		; CALL IT
	RET	NZ
	JR	FLUSHBF		; CONTINUE TILL NOTHING
CANCPM	LD	A,CAN
	CALL	SEND		; CALL THE SEND TO CANCEL
	LD	A,@DSPLY
	LD	HL,CANCDX
	RST	28H
	LD	HL,0FFFFH
	JP	RETTER		; GO BACK TO TERMINAL
CANCDX	DM	10,'! Transmit cancelled !',13
CPMDCB	DS	32
CPMBUF	DS	256
XMTBUF	DS	129
CPMFIL	DS	25
DONXM	LD	A,0FFH
	LD	(LASTB),A
	JP	SENDC
ENDXMT	LD	B,5		; TRY 5 TIMES
ENDXM1	LD	A,EOT
	CALL	SEND
WTCRL	CALL	GETFROM
	JR	NZ,XMW1		; RESEND IF NOTHING
	CP	ACK		; ACK?
	JR	Z,OKXT
XMW1	DJNZ	ENDXM1
	LD	HL,WRD
	LD	A,@DSPLY
	RST	28H
OKXT	LD	A,@DSPLY
	LD	HL,SDCCPM
	RST	28H
	LD	A,@CLOSE
	LD	DE,CPMDCB
	RST	28H
	LD	HL,0
	JP	RETTER
;
CERROR	PUSH	AF		; SAVE ERROR CODE
	LD	A,@DSPLY
	LD	HL,DSSS
	RST	28H
LVN	POP	AF		; WE RESTORE
	LD	C,A
	SET	6,C
	SET	7,C
	LD	A,@ERROR
	RST	28H		; PRINT ERROR MESSAGE
	LD	A,@DSPLY
	LD	HL,FRXN
	RST	28H
	LD	HL,0FFFFH	; ERROR!
	JP	RETTER
DSSS	DM	'? ',03
FRXN	DM	'! Fatal error in Xmodem mode -- exit !',13
SDCCPM	DM	'! Modem protocol filesend complete !',13
BLOCK	DB	0
OLDBIT7	DB	0
LASTB	DB	0
CPMRET	DB	0
WRD	DM	'! Terminator not correct -- exiting anyway !',13
RECVXY
;	ENTER HERE TO RECEIVE A XMODEM FILE. THE FILESPEC
;	MUST BE IN (HL).
;
	LD	(STORHLX),HL	; SAVE FOR LATER
	LD	A,@FSPEC
	LD	DE,CPMDCB
	RST	28H
	JP	NZ,RXERROR	; RECIEVE ERROR
	LD	A,@FLAGS
	RST	28H
	SET	0,(IY+18)	; SET READ ONLY
	LD	A,@OPEN		; WE TRY AN OPEN FIRST
	LD	DE,CPMDCB
	LD	HL,CPMBUF
	LD	B,0		; 0 LRL.
	RST	28H		; OPEN IT.
	JP	NZ,MAYROK	; MAY NOT EXIST.
	JP	NOEXBAT
MAYROK	CP	24		; FILE NOT HERE
	JP	NZ,RXERROR	; RECEIVE ERROR
MAYO3	LD	A,@FSPEC
	LD	HL,(STORHLX)
	LD	DE,CPMDCB
	RST	28H
	JP	NZ,RXERROR
	LD	A,@INIT
	LD	B,0
	LD	HL,CPMBUF
	LD	DE,CPMDCB
	RST	28H		; ATTEMPT TO INIT
	JP	NZ,RXERROR	; ERROR!
	CALL	WAIT5		; WAIT 5 SECONDS
	CALL	SETOFF
	LD	HL,RDYRCV
	LD	A,@DSPLY	; READY TO RECEIVE 
	RST	28H
	XOR	A		; RETRY COUNTER
	LD	(COUNTR),A	; COUNTER LOAD
	LD	A,1
	LD	(BLOCK),A
NAKIT	CALL	FLUSHBF		; FLUSH BUFFERS
	LD	A,NAK
	CALL	SEND		; SEND A <NAK>
	LD	B,10		; WAIT 10 SECONDS
WAITFOR	CALL	GETFROM
	JP	Z,GOXIN		; WE GOT SOMETHING!
	LD	A,@KBD
	RST	28H
	OR	A		; CHECK KB
	JP	NZ,RXCAN
	DJNZ	WAITFOR
	LD	A,(COUNTR)
	INC	A
	CP	10		; 10 RETRIES?
	JP	Z,RXCAN		; CANCEL RECEIVE
	LD	(COUNTR),A
	JR	NAKIT		; NAK IT AGAIN!
RXCAN	CALL	GETFROM		; GET ONE CHAR
	JR	Z,RXCAN
	LD	A,CAN
	CALL	SEND
	LD	HL,RXCCAN
	LD	A,@DSPLY
	RST	28H
	LD	A,@REMOV
	LD	DE,CPMDCB
	RST	28H		; KILL THE FILE
	LD	HL,CNC
	LD	A,@DSPLY
	RST	28H
	CALL	FLUSHBF
	LD	HL,0FFFFH
	JP	RETTER
CNC	DM	'! Receive cancelled, incomplete file deleted. !',13
GOXIN	PUSH	AF
	XOR	A
	LD	(COUNTR),A
	POP	AF
GOXMOR	CP	EOT		; END OF TRANSMIT
	JP	Z,ENDRCV
	CP	SOH		; IS IT SOH?
	JP	Z,SOHX		; GO GET BLOCK
	CP	CAN		; CANCEL?
	JP	Z,RXCAN
	JP	RESEND
SOHX	LD	HL,CPMI		; CLEAR INPUT BUFFER
	LD	DE,CPMI+1
	LD	BC,127		; WE ZERO 128 BYTES
	XOR	A
	LD	(HL),A
	LDIR			; ZERO IT
	CALL	GETFROM		; GET THE NEXT ONE
	JP	NZ,TIMOR	; TIMEOUT RECEIVE
	LD	B,A
	LD	A,(BLOCK)	; WE GET BLOCK NUMBER
	CP	B
	JP	Z,BLKOK		; THE BLOCK NUMBER IS OK
	DEC	A		; CHECK THIS ONE TOO
	CP	B
	JP	Z,RECVIGN	; IT'S A REPEAT
	JP	LOST
RECVIGN	CALL	FLUSHBF		; WAIT FOR LINE TO CLEAR
	LD	A,ACK
	CALL	SEND
	JP	CONTMX
BLKOK	CALL	GETFROM
	JP	NZ,TIMOR
	CPL
	LD	B,A
	LD	A,(BLOCK)
	CP	B
	JP	Z,CONV		; WE ARE OK!
	DEC	A
	CP	B		; CHECK LAST ONE
	JP	Z,RECVIGN
	JP	LOST
CONV	LD	B,128		; 128 BYTES/RECORD
	LD	C,0		; INITIALIZE CHECKSUM
	LD	HL,CPMI
RECV1	CALL	GETFROM
	JP	NZ,RESEND	; RE-SEND (NOT ENOUGH)
	LD	(HL),A
	INC	HL
	ADD	A,C
	LD	C,A
	LD	A,@KBD
	RST	28H		; SCAN KEYBOARD
	CP	80H		; IS IT A <BREAK>?
	JP	Z,RXCAN
	DJNZ	RECV1
GETCK	CALL	GETFROM
	JP	NZ,RESEND	; SOMETHING GOT LOST
	CP	C		; CHECK IT
	JP	NZ,RESEND	; RE SEND BLOCK
	LD	B,128
	LD	HL,CPMI
WRITI	LD	A,@PUT
	LD	DE,CPMDCB
	LD	C,(HL)
	PUSH	BC
	PUSH	HL
	RST	28H
	POP	HL
	POP	BC
	JP	NZ,RXERROR
	INC	HL
	DJNZ	WRITI
	LD	A,ACK
	CALL	SEND
	LD	A,(BLOCK)
	INC	A
	LD	(BLOCK),A
CONTMX	CALL	GETFRX
	JP	NZ,TIMOR	; TIMOUT ON RECEIVE
	JP	GOXMOR
;
TIMOR	LD	A,@REMOV
	LD	DE,CPMDCB
	RST	28H
	LD	HL,TIMORX
	LD	A,@DSPLY
	RST	28H
	LD	HL,0FFFFH
	JP	RETTER
TIMORX	DM	'! Timeout during receive - incomplete file deleted. !',13
;
;
RDYRCV	DM	'! File open, ready to receive !',10
	DM	'! Type ^X to cancel before transmission begins !',13
ENDRCV	LD	A,@CLOSE
	LD	DE,CPMDCB
	RST	28H
	LD	A,@DSPLY
	LD	HL,FILCOM
	RST	28H
	LD	A,ACK
	CALL	SEND
	JP	RETTER
FILCOM	DM	'! Modem protocol file received. !',13
RXERROR
	PUSH	AF
	LD	A,@DSPLY
	LD	HL,RXERM
	RST	28H
	POP	AF
	JP	CERROR		; ERROR HANDLING
RXERM	DM	'! ? Disk error during receive -- message follows !',13
CPMI	DS	129
COUNTR	DB	0
RXCCAN	DM	10,'! Cancelling receive. !',13
;
;
LOST	JR	RESEND		; TRY AGAIN.
RESEND	LD	A,(COUNTR)
	INC	A
	LD	(COUNTR),A
	CP	10		; 10 RETRIES?
	JR	Z,RESOUT
	CALL	FLUSHBX		; CLEAR INPUT
	LD	A,NAK
	CALL	SEND
	CALL	GETFRX
	JP	NZ,TIMOR
	JP	GOXMOR
RESOUT	LD	HL,RESX
	LD	A,@DSPLY
	RST	28H
	JP	RXCAN
GETFRX	PUSH	BC
	LD	B,SECWT		; USE THIS FOR # SECONDS
FFX	CALL	GETFROM
	JR	Z,GOB		; RETURN IF THERE IS ONE
	DJNZ	FFX		; CONTINUE TILL DONE
	XOR	A
	CP	1
	POP	BC
	RET			; RETURN WITH NZ RESULT
GOB	POP	BC
	RET			; RETURN WITH IT
RESX	DM	'! ? Block cannot be received !',13
FLUSHBX	CALL	GETFROM		; GET ONE WITH TIMEOUT
	RET	NZ		; RETURN IF NOTHING
	JR	FLUSHBX		; CONTINUE
NOEXBAT	LD	A,@DSPLY
	LD	HL,BATMX
	RST	28H
	LD	HL,0FFFFH
	JP	RETTER
BATMX	DM	'! ? Xmodem receive file exists - ABORT !',13
STORHLX	DW	0		; PLACE TO SAVE POINTER
;
;
;
START	LD	DE,PLACE
	LD	BC,50
	LDIR			; MOVE IT TO A SAFE PLACE
	LD	HL,XMODEM
	LD	A,@DSPLY
	RST	28H
	LD	HL,PLACE
	LD	A,(HL)
	CP	13		; CHECK IT OUT
	CALL	Z,GETPARMS
	LD	HL,PLACE	; CHECK IT OUT
	LD	B,80		; WE CHECK 80 CHARS
CHKIT	LD	A,(HL)		; CHECK IT OUT
	CP	13		; <ENTER>
	JR	Z,CXX		; NOTHING
	CP	3
	JR	Z,CXX		; NOTHING
	CP	'('		; OPEN PAREN'S?
	JR	Z,GETCCC
	INC	HL
	DJNZ	CHKIT
	JR	CXX
GETCCC	LD	DE,DEVNAME
	INC	HL
	LD	B,3
MOVIT	LD	A,(HL)
	LD	(DE),A
	INC	HL
	INC	DE
	DJNZ	MOVIT
CXX	LD	A,@FSPEC
	LD	DE,DCB
	LD	HL,DEVNAME
	RST	28H		; MOVE THE DEVICE NAME
	LD	A,@OPEN
	LD	DE,DCB
	LD	HL,BUFFER
	LD	B,0		; OPEN IT
	RST	28H		; DO IT!
	JP	NZ,NODEV	; NO DEVICE OF THAT NAME
	LD	HL,PLACE
	LD	A,(HL)		; CHECK IT AGAIN!
	CP	13		; <RET>?
	JP	Z,EXIT1		; LEAVE IF SO
	AND	0DFH
	CP	'S'		; SEND?
	JP	Z,SENDCPM	; SEND IF SO
	CP	'R'		; RECEIVE?
	JP	Z,RECVCPM	; GO TO IT IF SO
	LD	A,@DSPLY
	LD	HL,NOTLEG
	RST	28H
EXIT1	LD	A,@EXIT
	LD	HL,0
	RST	28H
NOTLEG	DM	'? Not a legal option. Options are:',10
	DM	'  S filename  - send a file to your end',10
	DM	'  R filename  - receive a file from your end',10
	DM	10,'  Please try again.',13
OKGO	LD	DE,DCB
	LD	A,@CTL
	LD	C,4
	LD	IY,INTHDL	; WE WANT TO ATTACH
	RST	28H		; DO IT!
	LD	(OLDIY),IY	; SAVE THE OLD ONE
	RET
SENDCPM	INC	HL		; SKIP NEXT
	INC	HL
	CALL	OKGO		; GO ATTACH THE RS-232
	LD	(OLDSTK),SP	; SAVE STACK
	JP	SENDXY		; SEND THE FILE
RECVCPM	INC	HL
	INC	HL
	CALL	OKGO
	LD	(OLDSTK),SP	; SAVE STACK
	JP	RECVXY
DCB	DS	32
BUFFER	DS	256
PLACE	DS	64
NODEV	LD	A,@DSPLY
	LD	HL,NODVR
	RST	28H
	LD	HL,0FFFFH
	RET			; NO DEVICE OF THAT NAME
NODVR	DM	'? No RS-232 device available.',13
XMODEM	DM	28,31
	DM	'** XMODEM TRS-80 Version 6.2.0',10
	DM	'   Written by Hal N. Fuquay',10
	DM	'   Released to public domain',10,13
	DM	'   TRSDOS 6.2.0 version only',13
DEVNAME	DM	'*RO',13
GETPARMS
	LD	HL,PARIN
	LD	A,@DSPLY
	RST	28H
	LD	HL,PLACE
	LD	B,50
	LD	A,@KEYIN
	RST	28H
	JP	C,LXV
	LD	A,B
	OR	A
	JP	Z,LXV
	RET			; RETURN TO THE PLACE.
PARIN	DM	'Enter direction, filename, and device as:',10,10
	DM	'S filename (*XX)',10
	DM	'     or',10
	DM	'R filename (*XX)',10
	DM	10,'Instructions? ',14,03
LXV	POP	AF		; RESTORE OLD PLACE
	LD	HL,0FFFFH
	RET			; RETURN TO CALLER
RETTER	PUSH	HL
	LD	A,@CTL
	LD	DE,DCB
	LD	C,4
	LD	IY,(OLDIY)
	RST	28H		; RESTORE OLD HANDLER
	CALL	WAIT5
	CALL	SETON
	LD	HL,DSPX
	LD	A,@DSPLY
	RST	28H
	POP	HL
	LD	SP,(OLDSTK)
	RET			; RETURN TO CALLER
DSPX	DM	10,'% Exiting',13
OLDSTK	DW	0
OLDIY	DW	0		; OLD IY LOCATION
INTHDL	DI			; NOT RE-ENTRANT!
	PUSH	DE
	PUSH	HL
	PUSH	AF
	PUSH	BC
	LD	DE,(BUFPOS)
	INC	DE
	LD	HL,(POSOF)
	XOR	A
	SBC	HL,DE
	LD	A,H
	OR	L
	JR	Z,NORES
	LD	HL,(POSIT)
	LD	DE,DCB
	LD	A,@GET
	RST	28H		; GET THE CHARACTER
	JR	NZ,NORES
	LD	(HL),A
	INC	HL
	LD	(POSIT),HL
	LD	HL,(BUFPOS)
	INC	HL
	LD	(BUFPOS),HL
	LD	DE,(LASTW)	; LAST LEGAL WORD
	XOR	A
	SBC	HL,DE
	LD	A,H
	OR	L
	JR	NZ,NORES
	LD	HL,INTBUF
	LD	(POSIT),HL
	LD	DE,0
	LD	(BUFPOS),DE
NORES	POP	BC
	POP	AF
	POP	HL
	POP	DE
	RET
POSIT	DW	INTBUF
BUFPOS	DW	0
POSOF	DW	0
POSRED	DW	INTBUF
GETCHAR	PUSH	HL
	PUSH	DE
	PUSH	BC
	PUSH	AF
	DI
	LD	HL,(BUFPOS)
	LD	DE,(POSOF)
	XOR	A
	SBC	HL,DE
	LD	A,H
	OR	L		; CHECK TO SEE IF SAME
	JR	Z,NOCHAR
	INC	DE
	LD	(POSOF),DE
	LD	HL,(POSRED)
	LD	C,(HL)
	INC	HL
	LD	(POSRED),HL
	LD	HL,(POSOF)
	LD	DE,(LASTW)
	XOR	A
	SBC	HL,DE
	LD	A,H
	OR	L
	JR	NZ,NORESX
	LD	HL,INTBUF
	LD	(POSRED),HL
	LD	DE,0
	LD	(POSOF),DE
NORESX	POP	AF
	LD	A,C
	POP	BC
	POP	DE
	POP	HL
	CP	A
	EI
	RET
NOCHAR	POP	AF
	POP	BC
	POP	DE
	POP	HL
	LD	A,0
	CP	1
	EI
	RET
BKMK	DB	0
SEND	PUSH	AF
	PUSH	BC
	PUSH	DE
	LD	C,A
WTX	LD	A,@PUT
	LD	DE,DCB
	RST	28H
	POP	DE
	POP	BC
	POP	AF
	RET			; RETURN TO CALLER
SETOFF	PUSH	HL		; SAVE COMMAND LINE
	LD	A,@CMNDR
	LD	HL,SETOF
	RST	28H		; SET IT OFF
	POP	HL		; RESTORE COMMAND LINE
	XOR	A
	RET			; RETURN
SETON	LD	A,@CMNDR
	PUSH	HL		; SAVE COMMAND LINE
	LD	HL,SETO
	RST	28H
	POP	HL		; RESTORE COMMAND LINE
	XOR	A
	RET
SETOF	DM	'Setcom (break=0,word=8)',13
SETO	DM	'Setcom (break=3)',13
LASTW	DW	256		; THE LAST PLACE (SUPPOSEDLY)
INTBUF	DB	0
	DS	257
;
TTON	DM	'TTY CRT',13
TTOF	DM	'TTY OFF',13
WAIT5	PUSH	BC
	PUSH	AF
	PUSH	DE
	LD	B,4
WT1	PUSH	BC
	LD	BC,60000
	LD	A,@PAUSE
	RST	28H
	POP	BC
	DJNZ	WT1
	POP	DE
	POP	AF
	POP	BC
	RET
	END	START
Downloaded from 8/N/1 #1 at 904/377-1200 - G. Omer