File SEED.RA

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/IDLE RANDOM NUMBER GENERATOR
	SECT8	SETIDL
	JA	#RET
	TEXT	+SETIDL+
SXR,	SETX	XR
	SETB	BP
BP,	F 0.0
XR,	F 0.0
	F 0.0
	F 0.0
	ORG	10*3+BP
	FNOP
	JA	SXR
	0
RET,	JA	.

	BASE	0
#RET,	STARTD
	FLDA	10*3
	FSTA	RET
	SETB	BP
	BASE	BP
	TRAP4	SET8	/GO TO 8 MODE STUFF.
	STARTF
	JA	RET	/DONE. ON IDLE QUEUE.

SET8,	0
	TAD	IDLAD	/FIELD OF IDLE ROUTINE
	CLL RTL
	RAL		/INTO BITS 6-8
	TAD	SCDF	/CDF TO #IDLE
	DCA	.+3
	TAD	IDLAD+1	/ADDRESS OF #IDLE
	DCA	IDLPTR
	0		/GETS CDF
	TAD	S7410	/SKP INSTRUCTION
	DCA%	IDLPTR	/STORE AT #IDLE
	TAD	JOB+1	/ADDRESS OF IDLE ROUTINE
	ISZ	IDLPTR
	DCA%	IDLPTR	/STORE AT #IDLE+1
	TAD	JOB
	CLL RTL
	RAL		/POSITION FIELD BITS
	TAD	SFIELD
	ISZ	IDLPTR
	DCA%	IDLPTR	/STORE AT #IDLE+2
	CIF CDF
	JMP%	SET8

	EXTERN	#IDLE
IDLAD,	ADDR	#IDLE
JOB,	ADDR	DOIT

SCDF,	6201
SFIELD,	6203
IDLPTR,	0
S7410,	0

DOIT,	0
	TAD	ROTWRD	/GET WORD TO DISPLAY
	ISZ	COUNT
	SKP
	JMP	OVER
	NOP
	NOP
	NOP
	NOP
	JMP	.-7
OVER,	RAL
	SZL
	CLL IAC		/PUT BIT BACK.
	DCA	ROTWRD
	TAD	SEEDPT
	CLL RTL
	RAL
	TAD	SCDF
	DCA	.+1
	0
	TAD	SEEDPT+1
	DCA	EXP
	CLL IAC
	TAD	EXP
	DCA	POINT
	TAD%	POINT
	TAD	K0100
	SPA
	JMP	OVRFLO
	DCA%	POINT
RETRN,	TAD	ROTWRD
	CIF CDF 0
	JMP%	DOIT

OVRFLO,	CLA CLL
	DCA%	POINT
	TAD%	EXP
	IAC
	AND	K0003
	DCA%	EXP
	JMP	RETRN

COUNT,	0
POINT,	0
EXP,	0
K0100,	100
K0003,	3
ROTWRD,	0017
	EXTERN	NUMCOM
SEEDPT,	ADDR NUMCOM	/SEED IS ONLY VARIABLE IN NUMCOM.


	END



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