/****** MULTI8 PTR EMULATOR ********
/LAST EDIT: 29-AUG-75, ELC
/CREATED: 20-DECEMBER-74, ELC
/SINGLE PAGE PAPERTAPE READER EMULATOR
/THIS TASK EXPECTS THE FOLLOWING THREE IOT'S FROM THE BACKGROUND:
/
/6011	SKIP-ON-READER-FLAG. THIS IOT IS INITIALY PACHED WITH
/	A SKIP. THIS MODULE WILL TAKE CARE OF ALL SYNCRONISATION
/	THUS THE 6011 IS PURE OVERHEAD THAT CAN BETER BE AVOIDED.
/	WE DO REMEMBER HOWEVER WHERE THE 6011 WAS IN THE USERS
/	PROGRAM. IF WE TIMEOUT THE TAPEREADER AT THE END
/	WE CHANGE THE SKP IN A NOP. NORMALY BG-PROGRAMS COUNT THE 
/	NUMBER OF 6011 THAT ARE NECESARRY TO GET THE NEXT
/	CHAR FROM THE
/	TAPE AND IF IT LASTS TOO LONG THEY DECIDE IT TO BE THE END
/	OF THE TAPE. SUCH A TIMEOUT LOOP WOULD TAKE QUITE SOME
/	TIME IF EVERY 6011 HAS TO BE EMULLATED. THUS BY PATCHING
/	IT WITH A NOP WE CAN LET IT GO AS SMOOTH AS NORMALLY.
/	NOTE THAT THE SAME READER ROUTINE IN THE BACKGROUND CAN'T
/	BE REUSED UNLESS THE NOP IS R
/6012 AND 6016	THIS ISTION. THUS
/	WE KICK THY) AND WAIT FOR THE
/	RE CHARACTER IS ORRED IN
/	THE USERS ACUUMULATOR AND WE RETURN. WHEN THE WAIT
/	EXITS WITH A TIMEOUT ERROR, WE GIVE A CONTROL-Z IN THE
/	USERS ACCUMULATOR, PATCH THE SKP TO A NOP AND MAKE
/	A FINAL EXIT+SWPOUT
/IS CONSIDDERRED SUPERFLO NOP.
	"R^100+"E&3777OUT CONNECTED INT'S
	0RE THE INTERRESTING THINGS
	SNA
	 JMP RECLR	/AC=0: RELEASE THIS DEVICE
	TAD C3		/AC IS POINTER TO BG-AREA
	DCA REUPC
	TAD REUPC
	IAC
	JMS DEFER
	AND C70		/GET CURRENT INSTRUCTION FIELD
	TAD C6201
	DCA RECDF	/SETUP FOR PATCHES
	STA
	TAD I REUPC
	DCA REPNT	/POINTER TO CURRENT INSTRUCTION
	TAD REUPC
	TAD C2
	DCA REUAC
	TAD REUAC
	IAC
	JMS DEFER	/GET THE TRAPPED INSTRUCTION
	RTR
	SPA CLA
	 JMP RESKP	/IOP1: SKIP
	SNL
	 JMP RENOP	/NOT IOP2
RERFC,	RFC		/IOP2: READ
	DCA .-1		/RFC ONE TIME ONLY TO START TAPE
	TAD (-DGNTICK%5!7700	/.2 SECONDS TIMEOUT
	JMS MONITOR
	   WAIT
	   PTR
	SZA CLA
	 JMP REEND	/TIMED OUT
	TAD I REUAC
	RRB RFC		/OR-IN NEW CHAR, KICK READER
	DCA I REUAC	/GIVE BACK TO USER
RERET,	JMS MONITOR
	   RETURN

RESKP,	ISZ I REUPC	/SKIP FIRST TIME TOO
	TAD REPNT
	DCA RESAVE	/REMEMBER WHERE RSF WAS
	TAD (SKP-NOP
RENOP,	TAD (NOP
RECDF,	CDF		/CDF TO USERS INSTRUCTION FIELD
	DCA I REPNT
	CDF MONFLD
	JMP RERET

REEND,	TAD RDF TO USERS RSF-FIELD
	FOR  A SMOOT TIMEOUT LOOONFLD
	TAD I REUAC
	ANCA I REUAC	/OR-IN A ^Z
RECLR,	TAD (RFC
	DCA RERFC	/REINITIALISE READER ROUTINE
	JMS MONITOR
	   EXIT SWPOUT	/THIS IS THE END

REUPC,	0
REUAC,	0
REPNT,	0
RESAVE,	0

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