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*20
/COPYRIGHT 1971 DIGITAL EQUIPMENT CORPORATION
/MAYNARD, MASSACHUSETTS
/BINARY LOADER PROGRAM
	 
	 
	PDP
	PMODE
	*7612
SWITCH,	0
MEMTEM,	0
CHAR,	0
CHKSUM,	0
ORIGIN,	0
	 
	*7626
/EXTRACT ERRORS, FIELD, L/T
BEGG,	0
	DCA SWITCH	/SET SWITCH
	JMS READ	/GET A CHARACTER
	TAD M376	/TEST FOR 377
	SPA SNA CLA
	JMP .+4		/NO
	ISZ SWITCH	/YES: COMPLEMENT SWITCH
	CMA
	JMP BEGG+1
	TAD SWITCH	/NOT 377
	SZA CLA		/IS SWITCH SET?
	JMP BEGG+2	/YES; IGNORE
	TAD CHAR	/NO; TEST FOR CODE
	AND MASK	/TYPES
	TAD M200
	SPA
	ISZ BEGG	/DATA OR ORIGIN
	SPA SNA CLA
	JMP I BEGG	/DATA, ORIGIN OR L/T
	 
	TAD CHAR	/FIELD SETTING
	AND FMASK
	TAD CHANGE
	DCA MEMTEM
	JMP BEGG+2	/CONTINUE INPUT
FMASK,	70
CHANGE,	CDF
READ,	0
	0
LOR,	KSF		/WAIT FOR FLAG
	JMP .-1
	KRB
	DCA CHAR
	TAD CHAR
	JMP I READ
HIR,	RSF
	JMP .-1
	RRB RFC
	JMP LOR+3
MASK,	300
	 
/TRAILER CODE SEEN
BEND,	JMS ASSEMB
	CIA
	TAD CHKSUM
M376,	HLT
BEGIN,	KCC
	RFC
	RDF
	TAD CHANGE
	DCA MEMTEM	/SAVE FIELD INSTRUCTION
	CLA OSR
	SMA CLA
	TAD HIRI
	TAD LORI
	DCA READ+1
	JMS BEGG
	JMP .-1		/IGNORE LEADER
	 
GO,	DCA CHKSUM
	TAD MEMTEM
	DCA MEMFLD
	TAD CHAR
	DCA WORD1
	JMS READ
	DCA WORD2
	JMS BEGG	/LOOK AHEAD
	JMP BEND	/TRAILER, END
	JMS ASSEMB
	SNL
	JMP MEMFLD
	 
	DCA ORIGIN
CHEX,	TAD WORD1
	TAD WORD2
	TAD CHKSUM
	JMP GO
	 
MEMFLD,	0
	DCA I ORIGIN
	ISZ ORIGIN
M200,	7600
	JMP CHEX
	 
ASSEMB,	0
	TAD WORD1
	CLL RTL
	RTL
	RTL
	TAD WORD2
	JMP I ASSEMB
LORI,	JMP LOR
HIRI,	HIR-LOR
	0
	WORD1=7776
WORD2,	0
	 
	*7777
	JMP BEGIN