/COPYRIGHT 1971  DIGITAL EQUIPMENT CORPORATION
/MAYNARD, MASSACHUSETTS
/BINARY AND DECTAPE LOADERS FOR
/555 CONTROL

	*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
	SNA SPA 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
$