* (PL$U) REV 1.0 LOW LEVEL INCREMENTAL PLOTTER DRIVER
*
*    
* PROGRAM TITLE:  PL$U  (PL$U, PL$D, PL$L, PL$R, PL$PU, PL$PD,
*                        PL$UR,PL$UL,PL$DR,PL$DL)
*                 
*                 LOW LEVEL PEN PLOTTER ROUTINES
*
* REVISIONS: 
*            1.0 (2007-05-27)
*
* AUTHOR:	
*
*    PHILIPP HACHTMANN
*
*
* PURPOSE:	
*
*    LOW LEVEL PEN PLOTTER DRIVER ROUTINES PROVIDING HARDWARE
*    ABSTRACTION BY PROVIDING SIMPLE ROUTINES FOR PEN MOVEMENT.
*    
*    
* STORAGE:	
*
*    ??? (OCTAL)
*    ??? (DECIMAL)
*
*
* USAGE:	
*
*              CALL     PL$U  - STEP UP
*	       CALL     PL$D  - STEP DOWN
*              CALL     PL$L  - STEP LEFT
*              CALL     PL$R  - STEP RIGHT
*              CALL     PL$PU - RAISE PEN
*              CALL     PL$PD - LOWER PEN
*
*              CALL     PL$UR - STEP UP+RIGHT
*              CALL     PL$UL - STEP UP+LEFT
*              CALL     PL$DR - STEP DOWN+RIGHT
*              CALL     PL$DL - STEP DOWN+LEFT
*	
*
*
********************************************************************************
*
*
PADR	EQU	'40	PORT ADDRESS OF THE PLOTTER INTERFACE
*
*
	SUBR	PL$U,UP
	SUBR	PL$D,DOWN
	SUBR	PL$R,RGHT
	SUBR	PL$L,LEFT
	SUBR	PL$PU,PENU
	SUBR	PL$PD,PEND
	SUBR	PL$UR,UR
	SUBR	PL$UL,UL
	SUBR	PL$DR,DR
	SUBR	PL$DL,DL
*
*
	REL		THIS IS A RELOCATABLE OBJECT
	ORG	'0
*
*
OUT	DAC	**	DO THE MOVEMENT
	OTA	PADR
	JMP	*-1
	JMP*	OUT
*
*	
UP	DAC	**
	LDA	CUP
	JST	OUT
	JMP*	UP
*
*
DOWN	DAC	**
	LDA	CDWN
	JST	OUT
	JMP*	DOWN
*
*
RGHT	DAC	**
	LDA	CRGT
	JST	OUT
	JMP*	RGHT
*
*
LEFT	DAC	**
	LDA	CLFT
	JST	OUT
	JMP*	LEFT
*
*
PENU	DAC	**
	LDA	CPNU
	JST	OUT
	JMP*	PENU
*
*	
PEND	DAC	**
	LDA	CPND
	JST	OUT
	JMP*	PEND
*
*
UL	DAC	**
	LDA	CUP
	ADD	CLFT
	JST	OUT
	JMP*	UL
*
*
UR	DAC	**
	LDA	CUP
	ADD	CRGT
	JST	OUT
	JMP*	UR
*
*
DL	DAC	**
	LDA	CDWN
	ADD	CLFT
	JST	OUT
	JMP*	DL
*
*
DR	DAC	**
	LDA	CDWN
	ADD	CRGT
	JST	OUT
	JMP*	DR
*
*
*			CONSTANTS
CUP	OCT	'1
CDWN	OCT	'2
CLFT	OCT	'4
CRGT	OCT	'10
CPNU	OCT	'20
CPND	OCT	'40
*
*
	END