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;	CompuPro Interfacer board equates.

GBP0:	EQU	0		;Serial port zero
GBP1:	EQU	2		;Serial port one
GBDATA:	EQU	0		;Data on even I/O unit
GBSTAT:	EQU	1		;Status on odd I/O unit

GBTBMT:	EQU	0000_0001B	;Transmit buffer empty
GBDAV:	EQU	0000_0010B	;Data available
GBOPT:	EQU	0000_0100B	;Optional status line
GBPE:	EQU	0000_1000B	;Parity error
GBOR:	EQU	0001_0000B	;Overrun error
GBFE:	EQU	0010_0000B	;Framing error
GBCC:	EQU	0100_0000B	;RS 232 CC input
GBCB:	EQU	1000_0000B	;RS 232 CB input

GBRIE:	EQU	0000_0001B	;Receiver interrupt enable
GBTIE:	EQU	0000_0010B	;Transmitter interrupt enable
GBCD:	EQU	0000_0100B	;RS 232 CD output
GBCA:	EQU	0000_1000B	;RS 232 CA output
GBTSB:	EQU	0001_0000B	;Number of stop bits
GBNP:	EQU	0010_0000B	;No parity
GBEPS:	EQU	0100_0000B	;Even parity
GBNBI:	EQU	1000_0000B	;number of bits/character

;	P u n c h   O u t p u t.
;
;	Send a character to the punch device.  If no punch
;	device exists then immediately return.
;
;	ENTRY	C = ASCII character to output.

PUNCH:
	if	@ldr <> 4
	INB	GBP1+GBSTAT
	AND	AL,#GBTBMT
	JZ	PUNCH		;If transmit buffer full
	MOV	AL,CL
	OUTB	GBP1+GBDATA
	endif
	RET
	SPACE	4,10
;	R e a d e r   I n p u t.
;
;	Read the next character from the currently assigned
;	reader device into the A register.
;
;	EXIT	A = character read from the reader device.

READER:
	if	@ldr <> 4
	INB	GBP1+GBSTAT	;Input from port
	AND	AL,#GBDAV	;Mask data available
	JZ	READER		;If data not available
	INB	GBP1+GBDATA
	endif
	RET
	SPACE	4,10
;	L i s t   O u t p u t.
;
;	Send a character to the list device.  If the list
;	device is not ready to receive a character wait
;	until the device is ready.
;
;	ENTRY	C = ASCII character to be output.

LIST:
	if	@ldr <> 4
	INB	GBP1+GBSTAT	;Get status
	AND	AL,#GBCC+GBTBMT
	SUB	AL,#GBTBMT
	JNZ	LIST
	MOV	AL,CL
	OUTB	GBP1+GBDATA
	RET
	ENDIF
	SPACE	4,10
;	L i s t   S t a t u s.
;
;	Return the ready status for the list device.
;
;	EXIT	A = 0 (zero), list device is not ready to
;		accept another character.
;		A = FFh (255), list device is ready to accept
;		a character.

LISTST:
	if	@ldr <> 4
	INB	GBP1+GBSTAT
	AND	AL,#GBCC+GBTBMT
	SUB	AL,#GBTBMT
	LD	AL,#0FFH
	JZ	LSTST1		;If not ready
	XOR	AL,AL		
LSTST1:
	endif
	RET