# Copyright: Public domain. # Filename: SXTMARK.agc # Purpose: Part of the source code for Comanche, build 055. It # is part of the source code for the Command Module's # (CM) Apollo Guidance Computer (AGC), Apollo 11. # Assembler: yaYUL # Reference: pp. 222-235 # Contact: Ron Burkey <info@sandroid.org>, # Fabrizio Bernardini <fabrizio@spacecraft.it> # Website: http://www.ibiblio.org/apollo. # Mod history: 16/05/09 FB Transcription Batch 2 Assignment. # # The contents of the "Comanche055" files, in general, are transcribed # from scanned documents. # # Assemble revision 055 of AGC program Comanche by NASA # 2021113-051. April 1, 1969. # # This AGC program shall also be referred to as Colossus 2A # # Prepared by # Massachusetts Institute of Technology # 75 Cambridge Parkway # Cambridge, Massachusetts # # under NASA contract NAS 9-4065. # # Refer directly to the online document mentioned above for further # information. Please report any errors to info@sandroid.org. # Page 222 # PROGRAM NAME - SXTMARK DATE- 5 APRIL 1967 # PROGRAM MODIFIED BY 258/278 PROGRAMMERS LOG SECTION SXTMARK # MOD BY- R. MELANSON TO ADD DOCUMENTATION ASSEMBLY SUNDISK REV. 116 # FUNCTIONAL DESCRIPTION- # SXTMARK IS CALLED FROM INTERNAL ROUTINES WHICH MAY REQUIRE STAR OR LANDMARK MARKINGS BY THE ASTRONAUT. IF # THE MARK SYSTEM IS NOT IN USE, SXTMARK RESERVES A VAC AREA FOR MARKING AND REQUESTS EXECUTION OF THE MKVB51 # ROUTINE VIA THE EXECUTIVE JOB PRIORITY LIST. R21 USES THIS ROUTINE TO DETERMINE IF THE MARK SYSTEM CAN BE # USED. IF YES, SXTMARK RETURNS TO R21 TO PERFORM ITS OWN MARK REQUESTS VIA THE V51 FLASH. # CALLING SEQUENCE- # CAF (NO. MARK REQUESTS IN BITS 1-3 OF A) # TC BANKCALL # CADR SXTMARK # NORMAL EXIT MODE- # SWRETURN # ALARM OR ABORT EXIT MODE- # ABORT # OUTPUT- # 1) MARKSTAT CONTAINS MARK VALUE (BITS 14-12) AND VAC AREA ADDRESS # 2) QPRET = VAC AREA POINTER VALUE # 3) 1ST WORD OF RESERVED VAC AREA SET TO +0 # 4) PRIO32 PLACED IN A REGISTER # ERASABLE INITIALIZATION- # 1) BITS 1-3 OF A = NO. MARKS REQUESTED # 2) BITS 2,3 OF EXTVBACT =0 # 3) A VAC AREA MUST BE AVAILABLE (WORD 1 = ADDRESS OF VAC AREA) # DEBRIS- # A,Q,L,RUPTREG1,MARKSTAT,QPRET,BIT2 OF EXTVBACT BANK 13 SETLOC SXTMARKE BANK EBANK= MRKBUF1 COUNT 07/SXTMK SXTMARK INHINT TS RUPTREG1 # NUMBER OF MARKS WANTED CAF SIX # BIT2 = MARKING SYSTEM IN USE MASK EXTVBACT # BIT3 = EXTENDED VERB IN PROGRESS CCS A TC MKABORT # SET THEREFORE ABORT # Page 223 CAF BIT2 # NOT SET ADS EXTVBACT # SET IT, RESET IN ENDMARK TC MARKOK # YES, FIND VAC AREA MKABORT TC BAILOUT OCT 01211 MARKOK CCS VAC1USE # FIND VAC AREA TC MKVACFND CCS VAC2USE TC MKVACFND CCS VAC3USE TC MKVACFND CCS VAC4USE TC MKVACFND CCS VAC5USE TC MKVACFND TC BAILOUT OCT 01207 MKVACFND AD TWO # ADDRESS OF VAC AREA TS MARKSTAT INDEX A TS QPRET # STORE NEXT AVAILABLE MARK SLOT CAF ZERO # STORE VAC AREA OCCUPIED INDEX MARKSTAT TS 0 -1 TC CHECKMM # BACKUP MARK ROUTINE USES SXTMARK MM 53 TCF +2 TCF SWRETURN TC CHECKMM MM 54 TCF +2 TCF SWRETURN CAF BIT12 # DESIRED NUMBER OF MARKS IN 12-14 EXTEND MP RUPTREG1 XCH L ADS MARKSTAT CAF PRIO32 # ENTER MARK JOB TC NOVAC EBANK= MARKSTAT 2CADR MKVB51 RELINT TCF SWRETURN # SAME AS MODEEXIT # Page 224 # PROGRAM NAME - MKRELEAS DATE- 5 APRIL 1967 # PROGRAM MODIFIED BY 248/278 PROGRAMMERS LOG SECTION SXTMARK # MOD BY- R. MELANSON TO ADD DOCUMENTATION ASSEMBLY SUNDISK REV. 116 # FUNCTIONAL DESCRIPTION- # MKRELEAS IS EXECUTED BY INTERNAL ROUTINES TO RELEASE THE MARK SYSTEM TO MAKE IT AVAILABLE TO OTHER INTERNAL # SYSTEM ROUTINES. IT ALSO CLEARS THE COARSE OPTICS FLAG BIT AND DISABLES THE OPTICS ERROR COUNTER. # CALLING SEQUENCE- # TC BANKCALL # CADR MKRELEAS # NORMAL EXIT MODE- # SWRETURN # ALARM OR ABORT EXIT MODE- NONE # OUTPUT- # 1) BIT9 OPTMODES SET TO 0 # 2) OPTIND SET TO -1 # 3) 1ST WORD OF VAC AREA SET TO VAC ADDRESS TO SIGNIFY AVAILABILITY. # 4) MARKSTAT CLEARED # 5) BIT2 CHANNEL 12 SET TO 0 # ERASABLE INITIALIZATION- NONE # DEBRIS- # A,MARKSTAT,BIT9,OPTMODES OPTIND,BIT2 CHANNEL 12 MKRELEAS CAF ZERO # SHOW MARK SYSTEM NOW AVAILABLE XCH MARKSTAT MASK LOW9 CCS A INDEX A TS 0 MKRLEES INHINT CS BIT9 # COARSE OPTICS RETURN FLAG. MASK OPTMODES TS OPTMODES CA NEGONE TS OPTIND # KILL COARSE OPTICS CS BIT2 # DISABLE OPTICS ERROR COUNTER EXTEND WAND CHAN12 RELINT TC SWRETURN # Page 225 # PROGRAM NAME - MARKRUPT DATE- 5 APRIL 1967 # PROGRAM MODIFIED BY 258/278 PROGRAMMERS LOG SECTION SXTMARK # MOD BY- R. MELANSON TO ADD DOCUMENTATION ASSEMBLY SUNDISK REV. 116 # FUNCTIONAL DESCRIPTION- # MARKRUPT STORES CDUS,OPTICS AND TIME AND TRANSFERS CONTROL TO THE MARKIT,MARK REJECT OR KEYCOM ROUTINES IF # BITS IN CHANNEL 16 ARE SET AS REQUIRED. # CALLING SEQUENCE- # ROUTINE ENTERED VIA KEYRUPT2 WHEN MARK,MARK REJECT OR DSKY KEYS DEPRESSED BY THE OPERATOR. # NORMAL EXIT MODE- # MARKIT, MKREJECT, OR POSTJUMP ROUTINES (MARK,MARK REJECT, OR DSKY CODE) # ALARM OR ABORT EXIT MODE- # ALARM AND RESUME # OUTPUT- # RUPTSTOR+5 = CDUT, RUPTSTOR+3 = CDUS, RUPTSTOR+2 = CDUY, # RUPTREG3 = CDUZ, RUPTSTOR+6 = CDUX, RUPTSTOR+1 AND SAMPTIME+1 =TIME1, # RUPTSTOR AND SAMPTIME = TIME2 # ERASABLE INITIALIZATION- # CDUT,CDUS,CDUY,CDUZ,CDUX,TIME2,TIME1,CHANNEL 16 BITS 6,7 OR 1-5 # DEBRIS- # A,QRUPT,RUPTREG3,SAMPTIME,SAMPTIME+1,RUPTSTOR TO RUPTSTOR+6 EXCEPT RUPTSTOR+4 (LOCATION 67) MARKRUPT TS BANKRUPT # STORE CDUS AND OPTICS NOW CA CDUT TS MKCDUT CA CDUS TS MKCDUS CA CDUY TS MKCDUY CA CDUZ TS MKCDUZ CA CDUX TS MKCDUX EXTEND DCA TIME2 # GET TIME DXCH MKT2T1 EXTEND DCA MKT2T1 DXCH SAMPTIME # RUPT TIME FOR NOUN 65. XCH Q TS QRUPT CAF BIT6 # SEE IF MARK OR MKREJECT # Page 226 EXTEND RAND NAVKEYIN CCS A TC MARKIT # ITS A MARK CAF BIT7 # NOT A MARK, SEE IF MKREJECT EXTEND RAND NAVKEYIN CCS A TC MKREJECT # ITS A MARK REJECT KEYCALL CAF OCT37 # NOT MARK OR MKREJECT, SEE IF KEYCODE EXTEND RAND NAVKEYIN EXTEND BZF +3 # IF NO INBITS TC POSTJUMP CADR KEYCOM # IT,S A KEY CODE, NOT A MARK. +3 TC ALARM # ALARM IF NO INBITS OCT 113 TC RESUME # Page 227 # PROGRAM NAME - MARKCONT DATE- 19 SEPT 1967 # PROGRAM MODIFIED BY 258/278 PROGRAMMERS LOG SECTION SXTMARK # MOD BY- R. MELANSON TO ADD DOCUMENTATION ASSEMBLY SUNDISK REV. 116 # FUNCTIONAL DESCRIPTION- # MARKCONT IS USED TO PERFORM A SPECIAL MARK FUNCTION FOR R21, TO EXECUTE A SPECIAL DISPLAY OF OPTICS AND TIME OR # TO PERFORM A MARK OF THE STAR OR LAND SIGHTING BASED UPON FLASHING V-N. # CALLING SEQUENCE- # FROM MARKDIF # NORMAL EXIT MODE- # TASKOVER # ALARM OR ABORT EXIT MODE- # ALARM AND TASKOVER # OUTPUT- # 1) FOR R21- # EBANK=EBANK7 # MRKBUF1 TO MRKBUF1+6 = TIME2,TIME1,CDUY,OPTICX,CDUZ,OPTICSY,CDUX OF CURRENT R21 MARK FUNCTION. # MRKBUF2 TO MRKBUF2+6 CONTAINS PREVIOUS R21 MARK VALUES. # 2) FOR SPECIAL DISPLAY JOB- # RUPTREG1 AND MRKBUF1 = CDUS,RUPTREG2 AND MRKBUF1 +1 = CDUT. # RUPTREG3 AND MRKBUF1 +2 = TIME2,RUPTREG4 AND MRKBUF1 +3 = TIME1 # 3) FOR NORMAL MARKING- # DECREMENT BITS14-12 OF MARKSTAT BY 1, # BIT10 MARKSTAT SET TO 1,INCREMENT QPRET BY 7, # STORE TIME2,TIME1,CDUY,CDUS,CDUZ,CDUT AND CDUX IN VAC+1 TO VAC+7 # ERASABLE INITIALIZATION- # 1) FOR R21- # BIT14 OF STATE+2 =1, MRKBUF1 TO MRKBUF1+6, ITEMP1, RUPTREG3, # RUPTSTOR TO RUPTSTOR+6 EXCEPT RUPTSTOR+4 # 2) FOR SPECIAL DISPLAY JOB- # BIT14 OF STATE+2 =0,MARKSTAT =+0,RUPTREG1,RUPTREG2,RUPTREG3 # RUPTREG4,RUPTSTOR,RUPTSTOR+1,RUPTSTOR+3,RUPTSTOR+5, # BIT12 OF STATE+5 (V59 FLAG),MRKBUF1 THRU MRKBUF1+3 # 3) FOR NORMAL MARKING- # BIT14 OF STATE+2 =0,MARKSTAE =VAC ADDRESS, A REG, ITEMP1, RUPTREG3, # RUPTSTOR TO RUPTSTOR+6 EXCEPT RUPTSTOR+4. # DEBRIS- # 1) FOR R21- # A,ITEMP1,MRKBUF1,MRKBUF2 # 2) FOR SPECIAL DISPLAY JOB- # A,RUPTREG1,RUPTREG2,RUPTREG3,RUPTREG4,MPAC TO MPAC+3 # 3) FOR NORMAL MARKING- # A,MARKSTAT,ITEMP1,QPRET,VAC+1 TO VAC+7 OF VAC AREA IN USE # Page 228 MARKCONT CAF BIT14 MASK STATE +2 # R21 MARK (SPECIAL MARKING FOR R21) EXTEND BZF MARKET # NOT SET THEREFORE REGULAR MARKING MARKIT1 CAF SIX # SPECIAL FOR R21 TC GENTRAN # TRANSFER MRKBUF1 TO MRKBUF2 ADRES MRKBUF1 ADRES MRKBUF2 CAF SIX # TRANSFER CURRENT MARK DATA TO MARKBUF1 TC GENTRAN ADRES MKT2T1 ADRES MRKBUF1 TCF TASKOVER MARKET CCS MARKSTAT # SEE IF MARKS CALLED FOR TC MARK2 # COLLECT MARKS CAF TWO # IS MARKING SYSTEM IN USE (BIT2) MASK EXTVBACT EXTEND BZF MARKET3 # MARKING NOT CALLED FOR CAF BIT12 MASK STATE +5 # V59FLAG EXTEND BZF MARKET3 # IF V59FLAG NOT SET-MARK UNCALLED FOR CAF PRIO5 # CALIBRATION MARK (SET) FOR P23 TC NOVAC # SPECIAL DISPLAY JOB EBANK= MRKBUF1 2CADR MARKDISP CAF SIX TC GENTRAN # TRANSFER MARK DATE TO MARKDOWN ADRES MKT2T1 ADRES MARKDOWN CAF SIX TC GENTRAN # TRANSFER MARK DATA TO MRKBUF1 FOR ADRES MKT2T1 # SPECIAL DISPLAY OF SHAFT AND TRUNNION ADRES MRKBUF1 # IF V59 ACTING TCF TASKOVER MARKET3 TC ALARM OCT 122 # MARKING NOT CALLED FOR TCF TASKOVER 114ALM TC ALARM # MARK NOT WANTED OCT 114 TCF TASKOVER # Page 229 # STORE MARK DATA IN MKVAC AND INCREMENT POINTER MARK2 AD 74K # SEE IF MARKS WANTED-REDUCE MARKS WANTED EXTEND BZMF 114ALM # MARK NOT WANTED-ALARM TS MARKSTAT COM MASK BIT10 # SET BIT10 TO ENABLE REJECT ADS MARKSTAT MASK LOW9 TS ITEMP1 INDEX A XCH QPRET # PICK UP MARK SLOT-POINTER TS ITEMP2 # SAVE CURRENT POINTER AD SEVEN # INCREMENT POINTER INDEX ITEMP1 TS QPRET # STORE ADVANCED POINTER VACSTOR EXTEND DCA MKT2T1 INDEX ITEMP2 DXCH 0 CA MKCDUY INDEX ITEMP2 TS 2 CA MKCDUS INDEX ITEMP2 TS 3 CA MKCDUZ INDEX ITEMP2 TS 4 CA MKCDUT INDEX ITEMP2 TS 5 CA MKCDUX INDEX ITEMP2 TS 6 CAF PRIO34 # IF ALL MARKS MADE FLASH VB50 MASK MARKSTAT EXTEND BZF +2 TCF TASKOVER CAF PRIO32 TC NOVAC EBANK= MARKSTAT 2CADR MKVB50 TCF TASKOVER # Page 230 # PROGRAM NAME - MKREJECT DATE- 5 APRIL 1967 # PROGRAM MODIFIED BY 258/276 PROGRAMMERS LOG SECTION SXTMARK # MOD BY- R. MELANSON TO ADD DOCUMENTATION ASSEMBLY SUNDISK REV. 116 # FUNCTIONAL DESCRIPTION- # ROUTINE ALLOWS OPEATOR TO REJECT MARK MADE PRIOR TO ACCEPTANCE AND ALLOWS A NEW MARK TO BE MADE BY ASTRONAUT # CALLING SEQUENCE- # FROM MARKRUPT IF BIT7 OF CHANNEL 16 IS 1. # NORMAL EXIT MODE- # RESUME # ALARM OR ABORT EXIT MODE- # ALARM AND RESUME # OUTPUT- # 1) FOR R21- # MRKRUP1 SET TO -1 # 2) FOR NORMAL MARKING- # BIT10 MARKSTAT =0,INCREMENT NO. MARKS BY 1,DECREMENT QPRET BY 7 # ERASABLE INITIALIZATION- # 1) FOR R21- # BIT14 OF STATE+2 SET TO 1 # 2) FOR NORMAL MARKING- # BIT14 OF STATE+2 SET TO 0, MARKSTAT,QPRET # DEBRIS- # 1) FOR R21- # A,MARKSTAT,EBANK # 2) FOR NORMAL MARKING- # A,MARKSTAT,ITEMP1,QPRET MKREJECT CAF BIT14 MASK STATE +2 # R21 MARK (SPECIAL MARKING FOR R21) EXTEND BZF MRKREJCT # NOT SET THEREFORE REGULAR REJECT CA NEGONE # -1 (FOR R22) TS MRKBUF1 # -0 IN TIME IS FLAG TO R22 SIGNIFYING A TC RESUME # REJECTED MARK MRKREJCT CCS MARKSTAT # SEE IF MARKS BEING ACCEPTED TC REJECT2 TC ALARM # MARKS NOT BEING ACCEPTED OCT 112 TC RESUME REJECT2 CS BIT10 # SEE IF MARK HAD BEEN MADE SINCE LAST MASK MARKSTAT # REJECT, AND SET BIT10 TO ZERO TO XCH MARKSTAT # SHOW MARK REJECT # Page 231 MASK BIT10 CCS A TC REJECT3 TC ALARM # DONT ACCEPT TWO REJECTS TOGETHER OCT 110 TC RESUME REJECT3 CAF LOW9 # DECREMENT POINTER TO REJECT MARK MASK MARKSTAT TS ITEMP1 CS SEVEN INDEX ITEMP1 ADS QPRET # NEW POINTER CAF BIT12 # INCREMENT MARKS WANTED AND IF FIELD AD MARKSTAT # IS NOW NON-ZERO, CHANGE TO VB51 TO XCH MARKSTAT # INDICATE MORE MARKS WANTED MASK PRIO34 # INDICATE MORE MARKS WANTED CCS A TC RESUME CAF PRIO32 TC NOVAC EBANK= MARKSTAT 2CADR MKVB51 TC RESUME # Page 232 # PROGRAM DESCRIPTION MKVB51 AND MKVB50 # AUTHOR-BARNERT DATE-2-15-67 MOD-0 # PURPOSE FLASH V51N70,V51N43, OR V51 TO REQUEST MARKING, # AND V50N25 R1=16 TO REQUEST TERMINATE MARKING. # CALLING SEQUENCE AS JOB WITHIN SXTMARK # EXIT TO ENDMARK UPON RECEIPT OF V33, V34 CAUSES GOTOP00H, ENTER # RECYCLES THE DISPLAY # NOTE- SXTMARK AUTOMATICALLY CHANGES FROM CALLING MKVB51 TO MKVB50 WHEN # SUFFICIENT MARKS HAVE BEEN MADE, AND THE REVERSE WHEN A MARK # REJECT REDUCES THE NUMBER MADE BELOW THAT REQUIRED # SUBROUTINES CALLED- BANKCALL, GOMARK2,GOODEND,ENDMARK,WAITLIST # ALARM OR ABORT MODES - NONE # ERASABLE USED-VERBREG,MARKSTAT,QPRET,DSPTEM1 # OUTPUT MARKSTAT=VAC ADDRESS # QPRET= NO.MARKS MKVB51 TC BANKCALL # CLEAR DISPLAY FOR MARK VERB CADR KLEENEX CAF VB51 # DISPLAY MARK VB51 TC BANKCALL CADR GOMARK4 TCF TERMSXT # VB34-TERMINATE TCF ENTANSWR # V33-PROCEED-MARKING DONE TCF MKVB5X # ENTER-RECYCLE TO INITIAL MARK DISPLAY TERMSXT TC CLEARMRK # CLEAR MARK ACTIVITY. TC CHECKMM MM 03 TCF +2 TC TERMP03 TC POSTJUMP CADR TERM52 TERMP03 TC UPFLAG ADRES TRM03FLG ENTANSWR CAF LOW9 # PUT VAC ADR IN MARKSTAT AND NO. OF MASK MARKSTAT # MARKS MADE IN QPRET BEFORE LEAVING TS MARKSTAT # SXTMARK COM INDEX MARKSTAT AD QPRET # Page 233 EXTEND BZMF JAMIT # NO MARKS MADE, SHOW IT IN QPRET, R53 EXTEND # WILL PICK IT UP AND RECYCLE MP BIT12 # THIS PUTS NUMBER MARKS-1 IN A AD ONE JAMIT INDEX MARKSTAT # STORE NO OF MARKS MADE TS QPRET INHINT # SERVICE OPTSTALL INTERFACE WITH CAF FIVE TC WAITLIST EBANK= MARKSTAT 2CADR ENDMARKS TC ENDMARK # KNOCKS DOWN MARKING FLAG + DOES ENDOFJOB ENDMARKS CAF ONE TC IBNKCALL CADR GOODEND MKVB5X CAF PRIO34 MASK MARKSTAT # RE-DISPLAY VB51 IF MORE MARKS WANTED CCS A # AND VB50 IF ALL IN TCF MKVB51 MKVB50 CAF R1D1 # OCT 16 TS DSPTEM1 CAF V50N25 TCF MKVB51 +3 V50N25 VN 5025 VB51 VN 5100 OCT37 = LOW5 # PROGRAM NAME - MARKIT DATE- 19 SEPT 1967 # CALLING SEQUENCE # FROM MARKRUPT IF CHAN 16 BIT 6 = 1 # EXIT # RESUME # INPUT # CDUCHKWD. ALSO ALL INITIALIZATION FOR MARKCONT # OUTPUT # MKT2T1,MKCDUX,MKCDUY,MKCDUZ,MKCDUS,MKCDUT # ALARM EXIT # NONE MARKIT CCS CDUCHKWD TCF +3 # DELAY OF CDUCHKWD CS IF PNZ # Page 234 TCF +2 CAF ZERO AD ONE # 10 MS IF NO CHECK TC WAITLIST EBANK= MRKBUF1 2CADR MARKDIF TCF RESUME SETLOC SXTMARK1 BANK COUNT 20/SXTMK # PROGRAM NAME - MARKDIF DATE- 19 SEPT 1967 # CALLING SEQUENCE # WAITLIST FROM MARKIT # EXIT # TASKOVER TO IBNKCALL TO MARKCONT # INPUT # OUTPUT FROM MARKIT, INPUT TO MARKCONT, CDUCHKWD # OUTPUT # RUPTSTOR - RUPTSTOR+3,RUPTREG3,RUPTSTOR+5 - RUPTSTOR+6 # ALARM EXIT # ALARM AND TASKOVER MARKDIF CA CDUCHKWD # IF DELAY CHECK IS ZERO OR NEG,ACP MARK EXTEND BZMF MKACPT CS BIT1 TS MKNDX # SET INDEX -1 CA MKCDUX TC DIFCHK # SEE IF VEHICLE RATE TO MUCH AT MARK CA MKCDUY TC DIFCHK CA MKCDUZ TC DIFCHK MKACPT TC IBNKCALL CADR MARKCONT # MARK DATA OK, WHAT DO WE DO WITH IT DIFCHK INCR MKNDX # INCREMENT INDEX EXTEND INDEX MKNDX # Page 235 MSU CDUX # GET MARK(ICDU) - CURRENT(ICDU) CCS A TCF +4 TC Q TCF +2 TC Q AD NEG2 # SEE IF DIFFERENCE GREATER THAN 3 BITS EXTEND BZMF -3 # NOT GREATER TC ALARM # COUPLED WITH PROGRAM ALARM OCT 00121 TCF TASKOVER # DO NOT ACCEPT