--- /dev/null
+/3 TD8E SYSTEM RESIDENT (12K)
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+/
+/COPYRIGHT (C) 1974,1975 BY DIGITAL EQUIPMENT CORPORATION
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+/
+/THE INFORMATION IN THIS DOCUMENT IS SUBJECT TO CHANGE WITHOUT NOTICE
+/AND SHOULD NOT BE CONSTRUED AS A COMMITMENT BY DIGITAL EQUIPMENT
+/CORPORATION. DIGITAL EQUIPMENT CORPORATION ASSUMES NO RESPONSIBILITY
+/FOR ANY ERRORS THAT MAY APPEAR IN THIS DOCUMENT.
+/
+/THE SOFTWARE DESCRIBED IN THIS DOCUMENT IS FURNISHED TO THE PURCHASER
+/UNDER A LICENSE FOR USE ON A SINGLE COMPUTER SYSTEM AND CAN BE COPIED
+/(WITH INCLUSION OF DIGITAL'S COPYRIGHT NOTICE) ONLY FOR USE IN SUCH
+/SYSTEM, EXCEPT AS MAY OTHERWISE BE PROVIDED IN WRITING BY DIGITAL.
+/
+/DIGITAL EQUIPMENT CORPORATION ASSUMES NO RESPONSIBILITY FOR THE USE
+/OR RELIABILITY OF ITS SOFTWARE ON EQUIPMENT THAT IS NOT SUPPLIED BY
+/DIGITAL.
+/
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+/
+/
+/
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+/
+/
+\f *0
+
+ -3
+ DEVICE TD8E;DEVICE SYS;4211;6007;0;1341
+ DEVICE TD8E;DEVICE DTA0;4211;5007;0;1341
+ DEVICE TD8E;DEVICE DTA1;4211;SDTA1&177+5000;0;1341
+\f TDBEGN-TD77-1
+
+ RELOC 7360
+
+/THE BINARY GETS LOADED INTO 27220 INITIALY, AND
+/WRITTEN OUT AS PART OF RECORD 0. WHEN THE 30 WORD
+/BOOTSTRAP IS USED, THIS CODE GETS READ INTO 7400.
+
+
+
+ SDSS=6771
+ SDST=6772
+ SDSQ=6773
+ SDLC=6774
+ SDLD=6775
+ SDRC=6776
+ SDRD=6777
+
+TDBEGN, ZBLOCK 20
+TDBOOT, TAD K7600 /128 WORDS PER PAGE
+ DCA TDWCT
+ SDSS /WAIT FOR A BLOCK MARK (TAPE IS
+ JMP .-1 /STILL MOVING)
+ SDRC
+ AND TD77
+ TAD KM26 /IS IT A BLOCK MARK?
+ SZA CLA
+ JMP TDBOOT+2 /NO..WAIT A WHILE LONGER
+ SDRD /GET THE BLOCK NO.
+TDBKNO, TAD TDM14 /NEED DECTAPE BLOCKS 154 & 155 (REC. 66)
+ SZA CLA
+ JMP TDBOOT+2 /NOT YET, BUSTER
+TDRGRD, SDSS
+ JMP .-1 /NOW LET'S LOOK FOR A REVERSE GUARD WORD
+ SDRC
+ AND TD77
+ TAD KM32
+ SZA CLA
+ JMP TDRGRD /KEEP LOOKING FOR IT
+ JMS TDRQD
+ JMS TDRQD
+ JMS TDRQD /SKIP CONTROL WORDS
+ CDF 10 /LOAD UP FIELD 1
+TDREAD, JMS TDRQD /GET A DATA WORD
+ DCA I TDPTR
+ ISZ TDPTR /ARE WE DONE?
+ JMP TDREAD /NOT YET
+ ISZ TDBKNO /YES..LOOK AT BLOCK 15
+ TAD KCDF20
+ DCA TDREAD-1 /LOAD UP FIELD 2
+ ISZ M2 /DONE THIS JUNK?
+ JMP TDBOOT /GO DO FIELD 2
+ SDLC /STOP THE TAPE
+ CIF CDF 0
+ JMP I K7605
+\fTDM14, -154
+ -155 /USE RECORD 66
+TDPTR,
+TDWCT, 7600
+TDRQD, 0
+ SDSQ
+ JMP .-1
+ SDRD
+ JMP I TDRQD
+
+K7600, 7600
+KM26, -26
+KM32, -32
+KCDF20, CDF 20
+M2, -2
+K7605, 7605
+TD77, 77
+
+/ THIS BOOTSTRAP RESIDES IN BLOCK 0
+/ BLOCK 1/2 CONTAINS THE USUAL IMAGE OF 07600
+/ BLOCK 66 CONTAINS THE IMAGE OF 17600
+/ BLOCK 66 1/2 CONTAINS THE IMAGE OF 27600
+ RELOC
+\f *200
+
+/TD8E DECTAPE SYSTEM HANDLER
+/THIS HANDLER CAN DRIVE UNITS 0&1, AND IS PERMANENTLY
+/RESIDENT IN FIELDS 0&2.
+
+ RELOC 7600
+
+ VERSION="B&77
+
+ ZBLOCK 7
+SHNDLR, VERSION /UNIT 0 ENTRY POINT
+ CLA CLL
+ JMP SHND2
+C3, 3 /MUST BE HERE FOR BUILD
+S70, 70
+SDTA1, VERSION /UNIT 1 ENTRY
+ CLA CLL CML
+SC1000, TAD SDTA1 /DOUBLES AS CONSTANT 1000
+ DCA SHNDLR /GET ARGS AT SHNDLR
+SHND2, RAR /UNIT #
+ DCA SUNIT
+ RDF /SETUP FOR EXIT
+ TAD S6203
+ DCA EFLD
+ TAD I SHNDLR /FUNCTION WORD
+ SDLD /PUT IT IN DATA EGISTER
+ AND S70 /SDLD DOES NOT 0 AC..GET FIELD
+ TAD S6203 /CIF CDF N FOR TRANSFER FIELD
+ DCA TFLD
+ ISZ SHNDLR
+ TAD I SHNDLR /BUFFER ADDRESS
+ DCA BPTR
+ ISZ SHNDLR
+ TAD I SHNDLR /BLOCK #. TIMES 2 FOR REAL #
+ CLL RAL
+ DCA BLOCK
+ ISZ SHNDLR /POINT TO ERROR EXIT
+ CIF CDF 20 /PUT UNIT # INTO FIELD 2
+ TAD SUNIT
+ DCA I SUNIT2
+ JMP F2SET /TO FIELD 2 FOR INIT.
+
+F1GO, SDRD /INITIAL DIRECTION TO LINK
+ RAR
+ JMP RGO
+\fRENTER, TAD BPTR /DONE THIS BLOCK..NEXT ADDRESS
+ TAD SC200
+ DCA BPTR
+ ISZ BLOCK /NEXT TAPE BLOCK..CAN'T SKIP
+ CLL CML /FORCE FORWARD MOTION
+RGO, CLA CML RTR /LINK TO MOTION BIT
+ TAD SC1000
+ TAD SUNIT
+ SDLC /MOVE THE TAPE
+ SDSQ
+ JMP .-1
+ SDRD /KNOCK DOWN QUAD FLAG
+ SDSQ
+ JMP .-1
+ SDRD /THIS IS NEEDED, ELSE TIME ERROR!!!
+\f
+SRCH, SDSS /WAIT FOR A BLOCK MARK
+ JMP .-1
+ SDRC /GET MARK TRACK BITS
+ CLL RTL /DIRECTION TO LINK
+ AND SC374
+ TAD SM110 /IS IT A N END ZONE?
+ SNA
+ JMP SENDZ /YES
+ TAD SM20 /MAYBE A BLOCK MARK?
+ SZA CLA
+ JMP SRCH /NEITHER..KEEP GOING
+ SDRD /READ THE BLOCK #
+ SZL /IF REVERSE, LOOK 3 AHEAD OF TARGET
+ TAD C3
+ CMA
+ TAD BLOCK
+ CMA
+ SNA /IS IT THE RIGHT ONE?
+ JMP FOUND /YES
+SM110, CLA SNA SZL /SNA SUPERFLUOUS..ONLY SZL VALID
+ JMP SRCH /HEADED FOR IT..KEEP GOING
+SENDZ, SDRC
+ CLL RTL
+ SZL CLA /IF IN END ZONE FORWARD, GIVE ERROR
+ JMP RGO
+ CIF 20 /IF IT IS REALL END ZONE, AN ERROR
+ JMP ERROR
+
+FOUND, SZL CLA /RIGHT BLOCK..HOW ABOUT DIRECTION?
+ JMP RGO /WRONG..EXECUTE TURNAROUND
+ TAD BPTR
+TFLD, HLT /GETS CIF CDF N
+ CIF 20
+ JMP RDWT /LET'S TRANSFER DATA
+
+SEXIT, ISZ SHNDLR /NORMAL RETURN
+SEREX, TAD SUNIT /STOP THE TAPE
+ SDLC
+ CML CLA RAR /EITHER 0 OR 4000 IN AC ON RETURN
+EFLD, HLT
+ JMP I SHNDLR
+
+ BPTR=7755
+ BLOCK=7754
+ SUNIT=SDTA1
+
+S6203, 6203
+SC200, 200
+SC374, 374
+SM20, -20
+SUNIT2, SXUNIT
+ RELOC
+\f *400
+
+ RELOC 7600 /RUNS IN 27600
+
+XPTR, 0 /BUFFER POINTER
+F2SET, CLA CLL CMA RTL /3 ERROR TRIES
+ DCA TRYCNT
+ TAD SXUNIT /MAKE SURE TAPE IS STOPPED
+ SDLC
+F26203, CIF CDF 0
+ SDRD /FUNCTION WORD
+ CLL RAL
+ AND CX7600 /PAGE COUNT
+ DCA XPGCT
+ SDRD
+ DCA SXFUN /SAVE THE FUNCTION WORD
+ JMP F1GO
+
+RDWT, DCA XPTR /SAVE NEW BUFFER ADDRESS
+ TAD CX7600
+ DCA XWCNT /128 WORDS PER BLOCK
+REVGRD, SDSS /WAIT FOR REVERSE GUARD WORD
+ JMP .-1
+ SDRC
+ AND X77
+ TAD XM32 /IS IT REVERSE GUARD?
+ SZA CLA
+ JMP REVGRD /NO
+ TAD SXFUN
+SK7700, SMA CLA /READ OR WRITE?
+ JMP READ /READ
+ SDRC
+ AND C300 /ERRORS ON WRITE LOCKOUT AND TIME
+ SZA CLA
+ JMP ERROR
+ JMS RDQUAD /SKIP A WORD
+CX7600, 7600
+ TAD WRLP
+ TAD SXUNIT
+ SDLC /TURN ON THE WRITE
+ CLA CMA
+ JMS WRQUAD /WRITE 7777 IN REV. CHECKSUM
+ CLA CMA
+ DCA SCKSUM /AND ALSO IN COMPUTE CHECKSUM
+WRLP, TAD I XPTR
+ JMS WRQUAD /WRITE THE DATA
+ ISZ XPTR
+X77, 77 /JUST IN CASE
+ ISZ XWCNT /DONE 128?
+ JMP WRLP
+ JMS WRQUAD /WRITE AND CHECKSUM A WORD OF 0
+ JMS GETCHK /GET CHECKSUM
+ JMS WRQUAD
+ JMS WRQUAD /LET CHECKSUM GET WRITTEN
+\f
+RWCOM, SDST /CHECK FOR TIME AND CHECKSUM ERRORS
+ SZA CLA
+ JMP ERROR /NOTE THAT LINK IS OFF AT RWCOM
+ CIF CDF 0
+ TAD XPGCT /FINISHED TRANSFER?
+ TAD CX7600 /LINK GOES ON HERE
+ SNA
+ JMP SEXIT /YES..GETOUT
+ DCA XPGCT
+ JMP RENTER
+
+READ, JMS RDQUAD /SKIP CONTROL WORDS
+ JMS RDQUAD
+ JMS RDQUAD /GET CHECKSUM
+ AND X77
+ TAD SK7700
+ DCA SCKSUM
+SRDLP, JMS RDQUAD
+ DCA I XPTR
+ TAD I XPTR
+ JMS EQUFUN
+ ISZ XPTR
+C300, 300
+ ISZ XWCNT /DONE ALL?
+ JMP SRDLP /NO
+ JMS RDQUAD /READ AND CHECKSUM LAST WORD
+ JMS EQUFUN
+ JMS RDQUAD /GET CHECKSUM
+ AND SK7700
+ JMS EQUFUN
+ JMS GETCHK
+ JMP RWCOM
+
+ERROR, CLA CLL /THIS CAUSES SEARCH REVERSE AT RGO
+ CIF CDF 0
+ ISZ TRYCNT /EXHAUSTED ERROR TRIES?
+ JMP RGO
+ JMP SEREX /YES..FATAL EXIT
+
+WRQUAD, 0 /WRITE A 12 BIT WORD
+ SDSQ
+ JMP .-1
+ SDLD
+ JMS EQUFUN /SDLD LEAVES AC ALONE
+ JMP I WRQUAD
+
+RDQUAD, 0 /READ A 12 BIT WORD
+ SDSQ
+ JMP .-1
+ SDRD
+ JMP I RDQUAD
+\fEQUFUN, 0 /EQUIVALENCE CHECKSUM
+ CMA
+ DCA EQUTMP
+ TAD EQUTMP
+ AND SCKSUM
+ CIA
+ CLL RAL
+ TAD EQUTMP
+ TAD SCKSUM
+ DCA SCKSUM
+ JMP I EQUFUN
+
+GETCHK, 0
+ TAD SCKSUM
+ CLL CMA RTL
+ RTL
+ RTL
+ JMS EQUFUN
+ TAD SCKSUM
+ AND SK7700
+ JMP I GETCHK
+
+SXUNIT, 0
+XPGCT, 0
+SXFUN, 0
+TRYCNT, 0
+XWCNT, 0
+XM32, -32
+SCKSUM, 0
+EQUTMP, 0
+
+/THE LAST 4 LOCS. ARE FREE FOR USE BY BATCH
+ ZBLOCK 4
+ RELOC
+ $
+\f
projects / pdp8.git / blobdiff