; NUEP-1.INS - NUBYE insert for Epson QX-10 computers - 04/21/86
;
; Z80 SIO and Intel 8253 timer
;
; Note:  This is an insert, not an overlay.
;
; ========
;
; 04/21/86  Modified for NUBYE
; 07/17/85  Written for use with BYE5		- Irv Hoff
;
; ========
;
PORT	EQU	11H		; Data port
MDCTL1	EQU	PORT+2		; Status/Control port
TMR0	EQU	6		; 8253 baudrate generator port
TMR1	EQU	TMR0+1		; Vector port
;
; Now comes the time to decide how we set the baud rate.  Set it prop-
; erly for your particular 8253 timer configuration
;
BDVECT	EQU	0B6H		; QX-10 Vector word
;
BD300	EQU	416		; 300 baud
BD1200	EQU	104		; 1200 bps
BD2400	EQU	52		; 2400 bps
;
; See if we still have a carrier - if not, return with the zero flag set
;
MDCARCK:MVI	A,10H		; Reset status
	OUT	MDCTL1
	IN	MDCTL1		; Get status
	ANI	8		; Check for data carrier
	RET
;
; Disconnect and wait for an incoming call
;
MDINIT:	MVI	A,18H		; Reset channel
	OUT	MDCTL1
	MVI	A,4		; Setup to write register 4
	OUT	MDCTL1
	MVI	A,44H		; 1 stop, 8 bits, no parity, 32x
	OUT	MDCTL1
	MVI	A,5		; Setup to write register 5
	OUT	MDCTL1
	MVI	A,68H		; Clear RTS causing hangup
	OUT	MDCTL1
	PUSH	B		; Save in case it's being used elsewhere
	MVI	B,20		; 2 seconds delay to drop any carrier
;
OFFTI:	CALL	DELAY		; 0.1 second delay
	DCR	B
	JNZ	OFFTI		; Keep looping until finished
	POP	B		; Restore bc
	MVI	A,3		; Setup to write register 3
	OUT	MDCTL1
	MVI	A,0C1H		; Initialize receive register
	OUT	MDCTL1
	MVI	A,5		; Setup to write register 5
	OUT	MDCTL1
	MVI	A,0EAH		; Turn on RTS so modem can answer phone
	OUT	MDCTL1
;
	 IF	IMODEM		; If using intelligent modem
	CALL	IMINIT		; Go initialize
	 ENDIF			; IMODEM
;
	RET
;
; Input a character from the modem port
;
MDINP:	IN	PORT		; Get character
	RET
;
; Check the status to see if a character is available.	if not, return
; with the zero flag set.  If yes, use 0FFH to clear the flag.
;
MDINST:	IN	MDCTL1		; Get status
	ANI	1		; Check the receive ready bit
	RZ			; Return if none
	ORI	0FFH		; Otherwise, set the proper flag
	RET
;
; Send a character to the modem
;
MDOUTP:	OUT	PORT		; Send it
	RET
;
; See if the output is ready for another character.
;
MDOUTST:IN	MDCTL1
	ANI	4		; Check the transmit ready bit
	RET
;
; Reinitialize the modem and hang up the phone by dropping DTR and
; leaving it inactive.
;
MDQUIT:	 IF	IMODEM
	CALL	IMQUIT
	 ENDIF			; IMODEM
;
; Called by the main program after caller types BYE
;
MDSTOP:	MVI	A,5		; Setup to write register 5
	OUT	MDCTL1
	MVI	A,68H		; Clear DTR
	OUT	MDCTL1		; Causing Hang-Up
	IN	PORT		; Clear out garbage
	IN	PORT		; Make sure we're clear
	RET			; Not used
;
; The following reoutine sets the baudrate.  NUBYE asks for the maximum
; speed you have available.
;
SETINV:	ORI	0FFH		; Make sure zero flag is not set
	RET
;
SET300:	PUSH	H
	LXI	H,BD300
	JMP	SETBAUD
;
SET1200:PUSH	H
	LXI	H,BD1200
	JMP	SETBAUD
;
SET2400:PUSH	H
	LXI	H,BD2400
;
SETBAUD:MVI	A,BDVECT	; Get vector address
	OUT	TMR1		; Send to TMR
	MOV	A,L
	OUT	TMR0
	MOV	A,H
	OUT	TMR0		; Send rate
	POP	H
	XRA	A		; Say rate is OK
	RET
;
; end of insert
; -------------
