{"id":241,"date":"2025-06-04T15:23:38","date_gmt":"2025-06-04T15:23:38","guid":{"rendered":"https:\/\/icm.museum\/blog\/?p=241"},"modified":"2025-07-04T01:13:15","modified_gmt":"2025-07-04T01:13:15","slug":"archiving-dectapes","status":"publish","type":"post","link":"https:\/\/icm.museum\/blog\/?p=241","title":{"rendered":"Archiving DECtapes"},"content":{"rendered":"\n

Support for the project comes from your donations<\/a><\/em><\/p>\n\n\n

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an assortment of PDP-10 related DECtapes<\/em><\/figcaption><\/figure>\n<\/div>\n\n\n

DECtape is a block-oriented magnetic media format more akin to the floppy disk than 9 track tape. There are four prevailing formats: LINC, 18, 16 and 12 bit. For years DEC distributed diagnostics, system distributions and sources on DECtape and our library consists of somewhere between 500 ~ 800 tapes.<\/p>\n\n\n\n

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It is possible to use an OS\/8 utility called PIP10 on the PDP-8 to work with an 18-bit format tape on a 12-bit machine, but we only need to use the PDP-8\/e to create an image of the tape. We can do this using a stand alone DECtape dump utility written by Kyle Owen (and modified by Josh Dersch at Living Computers) which runs on a laptop and communicates with the PDP-8\/e via the main serial terminal. A complete image of a tape yields 592896 8-bit bytes and takes about 5 minutes to produce. These tape images are currently being stored on the SDF anonymous FTP server<\/a>. The tendmp utility<\/a> written by Lars Brinkhoff<\/a> can be used to list the directory and extract files from the tape.<\/p>\n\n\n\n

Label: 10NOV4\n 1. DTAMON SAV         8      1973-04-11\n 2. KICPU  CMD         2      1973-04-09\n 3. DBKAA  SAV        19      1972-03-16\n 4. DBKAB  SAV        21      1972-03-16\n 5. DBKAC  SAV        15      1972-03-16\n 6. DBKAD  SAV        16      1972-03-16\n 7. DBKAE  SAV        12      1972-03-16\n 8. DBKAF  SAV        16      1972-03-16\n 9. DBKAG  SAV         7      1972-03-16\n10. DBKAH  SAV        38      1972-03-16\n11. DBKAI  SAV        48      1974-12-13\n12. DBKAJ  SAV        36      1973-04-09\n13. DBKAK  SAV        58      1972-03-16\n14. DBKAL  SAV        61      1972-03-16\n15. DBKAM  SAV        41      1972-03-16\n16. DKISPL SAV         4      1973-03-16\nFree blocks: 172<\/code><\/pre>\n\n\n\n
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A distribution of the LISP 1.6 code for ELIZA \/ DOCTOR<\/em><\/figcaption><\/figure>\n\n\n\n
\tTHIS TAPE CONTAINS SOURCES AND SAVE FILES OF DOCTOR AND\nELIZA, ADAPTED FOR THE STANFORD A.I. LISP 1.6 SYSTEM AND COMPILED\nTO RUN UP TO SIX TIMES FASTER THAN PREVIOUS VERSIONS.\n(A FEW BUGS HAVE ALSO BEEN FIXED.)\n\n\n \tFILES ON THE TAPE:\n\n\tDOCPGM.LSP\tSOURCE OF THE LISP PROGRAM\n\tDOCPGM.LAP\tCOMPILED (LAP) CODE OF THE ABOVE PROGRAM\n\tDOCTOR.RLS\tTHE \"RULES\" FOR DOCTOR\n\tELIZA.RLS\tTHE \"RULES\" FOR ELIZA\n\tSPEC\t\tSPECIAL VARIABLE DECLARATIONS TO COMPILE DOCPGM\n\tDOCTOR.SAV\tSAVE FILE OF DOCTOR\n\tELIZA.SAV\tSAVE FILE OF ELIZA\n\tDUMP\t\tEXPRS FOR DUMPING DOCTOR CORE IMAGES\n\tDOCTOR.TXT\tTHIS BLURB\n\n\n\tPROCEDURE FOR CREATING A NEW DOCTOR OR ELIZA (RULES FOR DOCTOR\nONLY ARE GIVEN, ELIZA CALLS FOR THE OBVIOUS CHANGES)\n\n1.\tCOPY THIS DTA TO DISK\n2.\tIF YOU DO NOT WISH TO RECOMPILE DOCPGM GO TO STEP 5.\n3.\tCOMBINE SPEC AND DOCPGM.LSP USING PIP:\n.R PIP\n*DOCPGM_SPEC,DOCPGM.LSP\n*\n4.\tRUN THE LISP COMPILER AND COMPILE DOCPGM\n^C\n.R COMPLR\n*(COMPL DOCPGM)\n<RANDOM OUTPUT>\n*^C\n.\n5.\tGET LISP SET UP\n.R LISP 16\nALLOC Y\nFULL WDS=640\nBIN.PROG.SP=1540\nSPEC.PDL=200\nREG. PDL=300\nHASH=37\n\nAUXILIARY FILES?Y\nSMILE?\nALVINE?\nTRACE?\nLAP?Y\nDECIMAL?N\n*\n6.\tREAD IN THE COMPILED LAP CODE\n*(INC(INPUT DSK: (DOCPGM.LAP$\n<RANDOM OUTPUT>\n*\n7.\tREAD IN THE RULES\n*(INC(INPUT DSK: (DOCTOR.RLS$\n<MORE RANDOM OUTPUT>\n*\n8.\tCLEAN UP CRUD IN THE CORE IMAGE\n*(EXCISE)\n*(NOUUO NIL)\n*(REMOB \/%DEFIN DE DF DM PUTSYM GETSYM)\n*(GC)\n*^C\n.\n9.\tJFCL THE \"*\". THE ADDRESSES MAY CHANGE DEPENDING ON VERSION \nOF LISP.\n.E 6457\n006457\/ 051040 006455\t.D 255000 0 6457\n.\n10.\tSAVE THE PROGRAM\n.SAVE DSK DOCTOR\nJOB SAVED\n^C\n.\n\n\t\/ TONY LAUCK\t30-MAR-70<\/code><\/pre>\n\n\n\n
Tape imaging will be live streamed from time to time so please follow https:\/\/twitch.tv\/sdfpubnix <\/a>to get notified when we go live.  More to come!<\/em><\/p>\n\n\n\n
<\/p>\n","protected":false},"excerpt":{"rendered":"
Support for the project comes from your donations DECtape is a block-oriented magnetic media format more akin to the floppy disk than 9 track tape. There are four prevailing formats: LINC, 18, 16 and 12 bit. For years DEC distributed diagnostics, system distributions and sources on DECtape and our library consists of somewhere between 500…<\/p>\n","protected":false},"author":1,"featured_media":242,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_kad_post_transparent":"","_kad_post_title":"","_kad_post_layout":"","_kad_post_sidebar_id":"","_kad_post_content_style":"","_kad_post_vertical_padding":"","_kad_post_feature":"","_kad_post_feature_position":"","_kad_post_header":false,"_kad_post_footer":false,"_kad_post_classname":"","footnotes":""},"categories":[41,44],"tags":[43,3,42],"class_list":["post-241","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-kicki","category-software","tag-dectape","tag-pdp10","tag-software"],"_links":{"self":[{"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=\/wp\/v2\/posts\/241","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=241"}],"version-history":[{"count":5,"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=\/wp\/v2\/posts\/241\/revisions"}],"predecessor-version":[{"id":261,"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=\/wp\/v2\/posts\/241\/revisions\/261"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=\/wp\/v2\/media\/242"}],"wp:attachment":[{"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=241"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=241"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/icm.museum\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=241"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}