M	EQU	Byte Ptr 0[BX]
	TITLE	'Bitmap SCAN OUTPUT PROCESSOR'
DGROUP	GROUP	DATA
; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; ;                                                                          ;
; ;  SCANER : SCAN AND OUTPUT one 'PLOT STRIP' from BITMAP to PRINTER        ;
; ;           Monochrome printer                                             ;
; ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
;                                                                            ;
;  Revision : Dec. 14,  1983  File "SCANER.A86"     Version 1.0              ;
;  Dec-14-84: Check Console Key Press, allowing output to be stopped.        ;
;                                                                            ;
;  Scaner (pline, xw, pixl, mapend, mpty)                                    ;
;                                                                            ;
;  Function : SCAN and OUTPUT entire 'PLOT STRIP' from BITMAP to PRINTER.    ;
;                                                                            ;
;               for j = 1 to PLINE   ;loop to output one strip               ;
;                   call GSCAN       ;   output one line                     ;
;                 output GLF }       ;  Graphic LineFeed                     ;
;                                                                            ;
;  Input   : PLINE  - No. of print lines per plot strip                      ;
;            XW     - No. of bytes per print line                            ;
;            LSIZE  - Offset to the start of next line to output in Bitmap   ;
;            MAPEND - First Byte address pointer in BITMAP buffer            ;
;                                                                            ;
;  Output  : None                                                            ;
;                                                                            ;
;  Calls   : GSCAN  - Transpose and output Image buffer to printer           ;
;                                                                            ;
;----------------------------------------------------------------------------;
;  CALL SCANER
;  RET
;
	PUBLIC	SCANER
	Extrn	GSCAN:near, GLF:near, Check_abort:near
	dseg
;;;;;;	EXTRN	BITMAP:word
	Extrn	MAPEND:word, mpty:word, XMAX:word, YMAX:word
	EXTRN	YW:word, PLINE:word, NSTRIP:word, PIXL:word
	EXTRN	BYTEND:word, XW:word, BMIN:word, Abort_flg:byte
	PUBLIC  ISTBYT
ISTBYT	RS	02
	cseg
SCANER:
	MOV	Bx, Word Ptr MAPEND	;<BX> = first byte address in bitmap
					;       to start scanning bit pattern
	Mov	Word Ptr ISTBYT, Bx

	MOV	Cx, Word Ptr PLINE	;No. of Print Lines per Strip

;	PLINE = Outer loop count
;	for j = 1 to pline

JLOOP:	PUSH	CX		; Save pline count
	Push	Bx		; Save Byte Pointer

;	If Bitmap is empty, skip scanning data for output

	Cmp	Byte Ptr MPTY, 0	; Check Empty flag for this plane
	Je	jloop9

	Call	GSCAN		; Output one scan line
jloop9:
	CALL	glf		; Output Graphic LineFeed
	Pop	Bx		; Get Byte Pointer
	POP	CX		; Get PLINE count
	DEC	CX		; Decrement pline count, Done yet?
	JZ	sent

;	Check Console status

	Call	Check_abort
	Cmp	Byte Ptr Abort_flg, 0ffH
	Je	sent		; Stop output if abort flag is set

	Sub	Bx, Word Ptr BMIN
	Mov	Word Ptr ISTBYT, Bx	; Update Buffer Pointer
	Jmp	Jloop
sent:	RET			; Yes, Return

	END