# Copyright: Public domain. # Filename: DAPIDLER_PROGRAM.agc # Purpose: Part of the source code for Luminary 1A build 099. # It is part of the source code for the Lunar Module's (LM) # Apollo Guidance Computer (AGC), for Apollo 11. # Assembler: yaYUL # Contact: Ron Burkey . # Website: www.ibiblio.org/apollo. # Pages: 1410-1420 # Mod history: 2009-05-10 SN (Sergio Navarro). Started adapting # from the Luminary131/ file of the same # name, using Luminary099 page images. # # This source code has been transcribed or otherwise adapted from # digitized images of a hardcopy from the MIT Museum. The digitization # was performed by Paul Fjeld, and arranged for by Deborah Douglas of # the Museum. Many thanks to both. The images (with suitable reduction # in storage size and consequent reduction in image quality as well) are # available online at www.ibiblio.org/apollo. If for some reason you # find that the images are illegible, contact me at info@sandroid.org # about getting access to the (much) higher-quality images which Paul # actually created. # # Notations on the hardcopy document read, in part: # # Assemble revision 001 of AGC program LMY99 by NASA 2021112-61 # 16:27 JULY 14, 1969 # Page 1410 # THE DAPIDLER PROGRAM IS STARTED BY FRESH START AND RESTART. THE DAPIDLER PROGRAM IS DONE 10 TIMES # PER SECOND UNTIL THE ASTRONAUT DESIRES THE DAP TO WAKE UP, AND THE IMU AND CDUS ARE READY FOR USE BY THE DAP. # THE NECESSARY INITIALIZATION OF THE DAP IS DONE BY THE DAPIDLER PROGRAM. BANK 16 SETLOC DAPS1 BANK EBANK= AOSQ COUNT* $$/DAPID CHEKBITS EXTEND READ CHAN31 # IF BOTH BIT13 AND BIT14 ARE ONE, THEN COM # THE MODE SELECT SWITCH IS IN THE OFF MASK BIT13-14 # POSITION, AND SO THE DAP SHOULD BE OFF, EXTEND # WITH NO ATTITUDE ERROR DISPLAY. BZF MOREIDLE CS IMODES33 MASK BIT6 CCS A TCF JUMPDSP CS RCSFLAGS # IMU NOT USABLE. SET UP INITIALIZATION MASK BIT3 # FLAG FOR ATT ERROR DISPLAY ROUTINE. ADS RCSFLAGS TCF SHUTDOWN CHEKMORE CAF BIT10 # BIT 10 OF 30 IS PGNCS CONTROL OF S/C EXTEND RAND CHAN30 # BITS IN 30 ARE INVERTED CCS A TCF MOREIDLE RETURN # Page 1411 # DAPIDLER ENTRY. DAPIDLER LXCH BANKRUPT # INTERRUPT LEAD INS (CONTINUED) EXTEND QXCH QRUPT CA RCSFLAGS MASK BIT13 CCS A # CHECK IF 1/ACCJOB HAS BEEN SET UP SINCE TCF CHECKUP # THE LAST FRESH START OR RESTART. CA BIT13 ADS RCSFLAGS # BIT 13 IS 1. CAF PRIO27 TC NOVAC # SET UP JOB TO DO A LITTLE INITIALIZATION EBANK= AOSQ # AND EXECUTE 1/ACCS. 2CADR 1/ACCSET # (WILL BRANCH TO MOREIDLE ON ACCSOKAY) CHECKUP TC CHEKBITS # CHECK TO SEE IF LM DAP IS TO GO ON AND # DO ERROR DISPLAY. CAE DAPBOOLS # IF 1/ACCS HAS NOT BEEN COMPLETED, IDLE. MASK ACCSOKAY # NOTE: ONLY FRESH START AND RESTART EXTEND # KNOCK THIS BIT DOWN. BZF MOREIDLE STARTDAP TC IBNKCALL # ZERO ATTITUDE ERROR AND DESIRED RATES. FCADR ZATTEROR CAF ZERO # ************ INITIALIZE: ************* TS TJP TS TJU TS TJV TS OMEGAP # RATES IN BODY (PILOT) COORDINATES. TS OMEGAQ TS OMEGAR TS TRAPEDP TS TRAPEDQ TS TRAPEDR TS AOSQ # OFFSET ACCELERATION ESTIMATES. TS AOSQ +1 TS AOSR TS AOSR +1 TS ALPHAQ # COPIES OF OFFSET ESTIMATES FOR DOWNLIST. TS ALPHAR TS NEGUQ TS NEGUR TS AOSQTERM # QRAXIS RATE DERIVATION TERMS AND KALMAN TS AOSRTERM # FILTER INITIALIZATION TERMS. TS QACCDOT # DESCENT ACCELERATION DERIVATIVE EST. TS RACCDOT # Page 1412 TS ALLOWGTS # AOSTASK FLAG FOR QRAXIS RCS CONTROL USE. TS COTROLER # DO TRYGTS ON FIRST PASS (WILL GO TO RCS) TS INGTS # RECOGNIZE FIRST GTS PASS AS SUCH. TS QGIMTIMR # STOP GIMBAL DRIVES. (PROBABLY WOULD BE TS RGIMTIMR # GOOD ENOUGH JUST TO INACTIVATE TIMERS) TS OLDPMIN # MINIMUM IMPULSE MODE ERASABLES TS OLDQRMIN TS PJETCTR # INITIALIZE DOCKED JET INHIBITION TS UJETCTR # COUNTERS TS VJETCTR CALLGMBL EQUALS BIT5 # RCSFLAGS INITIALIZATION. CS MANFLAG MASK RCSFLAGS # NEGUQ(R) HAVE BEEN GENERATED. TS RCSFLAGS # SET UP "OLD" MEASURED CDU ANGLES: EXTEND DCA CDUX # OLDXFORP AND OLDYFORP DXCH OLDXFORP CA CDUZ TS OLDZFORQ CS RCSFLAGS MASK BIT12 ADS RCSFLAGS # BIT 12 SET TO 1. CA FOUR TS SKIPU TS SKIPV CA POSMAX TS TIME6 TS T6NEXT TS T6FURTHA CA ZERO TS T6NEXT +1 TS T6FURTHA +1 TS NXT6ADR TS NEXTP TS NEXTU TS NEXTV CS TEN TS DAPZRUPT # TASK NOT IN PROGRESS, INITIALIZE NEG. CA TWO TS NPTRAPS TS NQTRAPS TS NRTRAPS EXTEND DCA PAXADIDL DXCH T5ADR SETTIME5 CAF MS100 TS TIME5 # Page 1413 TCF RESUME EBANK= AOSQ IDLERADR 2CADR DAPIDLER MOREIDLE TC IBNKCALL # CALCULATE Q,R-AXES ATTITUDE ERRORS. CADR QERRCALC TC IBNKCALL CADR CALCPERR # CALCULATE P AXIS ATTITUDE ERRORS. SHUTDOWN EXTEND DCA IDLERADR DXCH T5ADR CAF ZERO # KILL ANY POSSIBLE JET REQUESTS TS NEXTP TS NEXTU TS NEXTV EXTEND # COMMAND JETS OFF. WRITE CHAN5 EXTEND WRITE CHAN6 CS BGIM23 # TURN TRIM GIMBAL OFF EXTEND WAND CHAN12 TCF SETTIME5 # RETURN IN 100 MSEC. MANFLAG OCT 03021 BGIM23 OCTAL 07400 EBANK= OMEGAP PAXADIDL 2CADR PAXIS MS100 = OCT37766 COSMG = ITEMP1 JUMPDSP EXTEND # TRANSFER TO BANK 20 DCA DSPCADR # FOR ATTITUDE ERROR DISPLAYS DTCB EBANK= AK DSPCADR 2CADR ALTDSPLY # Page 1414 BANK 20 SETLOC DAPS3 BANK COUNT* $$/NEEDL # PROGRAM: ALTDSPLY # MOD 0. 6 DEC 1967 # AUTHOR: CRAIG WORK, DON KEENE, MIT IL # MOD 3 BY DON KEENE AUG 1, 1968 -- MOVED PROGRAM TO BANK 20 # # PROGRAM DESCRIPTION: # ALTDSPLY REVERSES THE DSPLYALT BIT OF RCSFLAGS EACH TIME IT IS CALLED, WHICH IS PRESUMABLY EVERY 100 MS. # IF THE REVERSED BIT IS ONE, NEEDLER IS CALLED TO DISPLAY ATTITUDE ERRORS. IF THE BIT IS ZERO, THE ATTITUDE ERR- # ORS ARE CALCULATED AS 1) DAP FOLLOWING ERRORS, IF NEEDLFLG = 0, AND 2) TOTAL ATTITUDE ERRORS FOR NEEDLFLG = 1. # # # WARNING: ALTDSPLY MAY ONLY BE CALLED WITH INTERRUPT INHIBITED # # WARNING: EBANK MUST BE SET TO 6 WHEN USING THIS ROUTINE. # # INPUT: RCSFLAGS AND 1) IF NEEDLFLG = 0, INPUT PERROR, QERROR, RERROR. # 2) IF NEEDLFLG = 1, INPUT CPHI,CTHETA,CPSI,CDUX,CDUY,CDUZ,M11,M21,M32,M22,M32. (GPMATRIX) # # # OUTPUTS: RCSFLAGS WITH DSPLYALT REVERSED, AK, AK1, AK2, + NEEDLER OUTPUTS. # # ENTRY: TCF ALTDSPLY # # EXIT: TCF CHEKMORE # # ALARM OR ABORT EXITS: NONE # # SUBPROGRAMS CALLED: NEEDLER, OVERSUB2 # # DEBRIS: A, L, AND NEEDLER DEBRIS. ALTDSPLY CA RCSFLAGS # INVERT THE DISPLAY ALTERNATION BIT. TS L CA DSPLYALT EXTEND RXOR LCHAN TS RCSFLAGS MASK DSPLYALT CCS A # IS ALTERNATION FLAG ZERO? TCF NEEDLER CAE FLAGWRD0 # NEEDLFLG WILL INDICATE TOTAL OR DAP AT- # Page 1415 MASK NEEDLBIT # TITUDE ERROR DISPLAY REQUEST. CCS A TCF DSPLYTOT # TOTAL ERROR IS NEEDED IN AK, AK +1, AK +2 CS QERROR # YES. DISPLAY ATT ERRORS ON THE -BALL. TS AK +1 # ERROR COMPLEMENTS ARE INPUT TO NEEDLER. CS RERROR TS AK +2 CS PERROR XCH AK TCF RETNMORE # DISPLAY THESE THE NEXT TIME THROUGH # CALCULATE GIMBAL ANGLE TOTAL ERRORS, RESOLVE INTO PILOT AXES, STORE TOTAL ERRORS FOR NEEDLER. Q-AXIS FIRST. DSPLYTOT EXTEND QXCH ITEMP1 # SAVE Q FOR CHEKBITS RETURN. CA CTHETA # DESIRED ATTITUDE, Y-AXIS, 2'S COMP. EXTEND # SUBTRACT CURRENT ATTITUDE. MSU CDUY # DIFFERENCE SCALED AT PI, 1'S COMP. TS AK # SAVE FOR R-ERROR CALCULATION. EXTEND MP M21 # (CTHETA-CDUY)*M21 SCALED AT PI RADIANS. XCH AK +1 # STORE FIRST TERM OF Q ERROR. CA CPSI # DESIRED ATTITUDE, Z-AXIS, 2'S COMP. EXTEND # SUBTRACT CURRENT ATTITUDE. MSU CDUZ # DIFFERENCE SCALED AT PI, 1'S COMP. TS AK +2 # SAVE Z-AXIS TERM FOR R ERROR CALCULATION EXTEND MP M22 # (CPSI-CDUZ)*M22, SCALED AT PI RADIANS. AD AK +1 # Q ERROR COMPLETE , AT PI RAD. TC OVERSUB2 # PIN NEEDLES IN CASE OF OVERFLOW TS AK +1 # R ERROR CALCULATION NEXT. CA AK # Y-AXIS DIFFERENCE STORED BY Q-AXIS CALC. EXTEND MP M31 # (CTHETA-CDUY)*M31, SCALED AT PI RADIANS. XCH AK +2 # FIRST TERM OF R ERROR. # Z-AXIS DIFFERENCE, STORED BY A CALC. IS EXTEND # RECOVERED BY THE EXCHANGE. MP M32 # (CPSI-CDUZ)*M32, SCALED AT PI RADIANS. AD AK +2 # R ERROR COMPLETE , AT PI RAD. TC OVERSUB2 # PIN NEEDLES IN CASE OF OVERFLOW. TS AK +2 # NOW CALCULATE P ERROR. (NOTE THAT M13 = 1, SCALED AT 1, SO THE MULTIPLICATION IS BY-PASSED.) # Page 1416 CA AK # Y-AXIS DIFFERENCE STORED BY Q AXIS CALC. EXTEND MP M11 # (CTHETA-CDUY)*M11 SCALED AT PI RADIANS. XCH AK # FIRST TERM OF P ERROR IN AK, AT PI RAD. CAE CPHI # DESIRED ATTITUDE, X-AXIS, 2'S COMP. EXTEND # SUBTRACT CURRENT X ATTITUDE. MSU CDUX # X-AXIS DIFFERENCE, 1'S COMP, AT PI RAD. # M13 = 1, SO BYPASS THE MULTIPLICATION. # EXTEND # MP M13 # (CPHI-CDUX)*M13 SCALED AT PI RADIANS. AD AK # P ERROR COMPLETE , SCALED AT PI RAD TC OVERSUB2 # PIN NEEDLES IN CASE OF OVERFLOW. TS AK EXTEND QXCH ITEMP1 # RESTORE Q FOR CHEKBITS RETURN. TCF RETNMORE # DISPLAY THESE THE NEXT TIME THROUGH # Page 1417 # FDAI ATTITUDE ERROR DISPLAY SUBROUTINE # # PROGRAM DESCRIPTION: D. KEENE 5/24/67 # MOD 1 BY CRAIG WORK, 12 DEC 67 # MOD 2 BY CRAIG WORK, 6 APRIL 68, CONVERTS ATTITUDE ERROR DISPLAY SCALING FROM 16 7/8 DEG. TO 42 3/16 DEGREES. # # THIS SUBROUTINE IS USED TO DISPLAY ATTITUDE ERRORS ON THE FDAI VIA THE DIGITAL TO ANALOG CONVERTERS (DACS) # IN THE CDUS. CARE IS TAKEN TO METER OUT THE APPROPRIATE NUMBER OF PULSES TO THE IMU ERROR COUNTERS AND PREVENT # OVERFLOW, TO CONTROL THE RELAY SEQUENCING, AND TO AVOID INTERFERENCE WITH THE COARSE ALIGN LOOP WHICH ALSO USES # THE DACS. # # CALLING SEQUENCE: # DURING THE INITIALIZATION SECTION OF THE USER'S PROGRAM, BIT3 OF RCSFLAGS SHOULD BE SET TO INITIATE THE # TURN-ON SEQUENCE WITHIN THE NEEDLES PROGRAM: # CS RCSFLAGS # IN EBANK6 # MASK BIT3 # ADS RCSFLAGS # THEREAFTER, THE ATTITUDE ERRORS GENERATED BY THE USER SHOULD BE TRANSFERRED TO THE FOLLOWING LOCATIONS IN EBANK6: # AK SCALED 180 DEGREES NOTE: THESE LOCATIONS ARE SUBJECT # AK1 SCALED 180 DEGREES TO CHANGE # AK2 SCALED 180 DEGREES # FULL SCALED DEFLECTION OF THE NEEDLES CORRESPONDS TO 5 1/16 DEGREES, WHILE 384 BITS IN THE IMU ERROR COUNTER # CORRESPONDS TO 42 3/16 DEGREES. (DAC MAXIMUM CAPACITY IS 384 BITS.) 46 BITS EFFECTIVELY PIN THE NEEDLES. # # A CALL TO NEEDLER WILL THE UPDATE THE DISPLAY: # INHINT # TC IBNKCALL # NOTE: EBANK SHOULD BE SET TO E6 # CADR NEEDLER # RELINT # THIS PROCESS SHOULD BE REPEATED EACH TIME THE ERRORS ARE UPDATED. AT LEAST 3 PASSES THRU THE PROGRAM ARE # REQUIRED BEFORE ANYTHING IS ACTUALLY DISPLAYED ON THE ERROR METERS. # NOTE: EACH CALL TO NEEDLER MUST BE SEPARATED BY AT LEAST 50 MS. TO ASSURE PROPER RELAY SEQUENCING. # # ERASABLES USED: # AK CDUXCMD # AK1 CDUYCMD # AK2 CDUZCMD # EDRIVEX A,L,Q # EDRIVEY T5TEMP # EDRIVEZ DINDX # Page 1418 # # SWITCHES: RCSFLAGS BITS 3,2 # # I/O CHANNELS: CHAN12 BIT 4 (COARSE ALIGN -- READ ONLY) # CHAN12 BIT 6 (IMU ERROR COUNTER ENABLE) # CHAN14 BIT 13,14,15 (DAC ACTIVITY) # # SIGN CONVENTION: AK = THETAC - THETA # WHERE THETAC = COMMAND ANGLE # THETA = PRESENT ANGLE NEEDLER CA RCSFLAGS MASK SIX EXTEND BZF NEEDLES3 MASK BIT3 EXTEND BZF NEEDLER2 # BIT3 = 0, BIT2 = 1 CS BIT6 # FIRST PASS BIT3 = 1 EXTEND # DISABLE IMU ERROR COUNTER TO ZERO DACS WAND CHAN12 # MUST WAIT AT LEAST 60 MS BEFORE NEEDLE11 CS ZERO # ENABLING COUNTERS. TS AK # ZERO THE INPUTS ON FIRST PASS TS AK1 TS AK2 TS EDRIVEX # ZERO THE DISPLAY REGISTERS TS EDRIVEY TS EDRIVEZ TS CDUXCMD # ZERO THE OUT COUNTERS TS CDUYCMD TS CDUZCMD CS SIX # RESET RCSFLAGS FOR PASS2 MASK RCSFLAGS AD BIT2 TS RCSFLAGS TCF RETNMORE NEEDLER2 CAF BIT6 # ENABLE IMU ERROR COUNTERS EXTEND WOR CHAN12 CS SIX # RESET RCSFLAGS TO DISPLAY ATTITUDE MASK RCSFLAGS # ERRORS. WAIT AT LEAST 4 MS FOR TS RCSFLAGS # RELAY CLOSURE. TCF RETNMORE NEEDLES3 CAF BIT6 # CHECK TO SEE IF IMU ERROR COUNTER EXTEND # IS ENABLED RAND CHAN12 # Page 1419 CCS A # IF NOT, RE-INITIALIZE NEEDLER. TCF NEEDLES CS RCSFLAGS # SET UP INITIALIZATION FLAG IN RCSFLAGS. MASK BIT3 ADS RCSFLAGS TCF RETNMORE NEEDLES CAF TWO DACLOOP TS DINDX CS ONETENTH # RESCALE INPUTS TO + OR - 1800 DEGREES. EXTEND INDEX DINDX MP AK TS L CCS A CA DACLIMIT TCF +2 CS DACLIMIT AD L TS T5TEMP # OVFLO CHK TCF +4 INDEX A # ON OVERFLOW LIMIT OUTPUT TO +-384 CAF DACLIMIT TS L INDEX DINDX CS EDRIVEX # CURRENT VALUE OF DAC AD L INDEX DINDX ADS CDUXCMD INDEX DINDX LXCH EDRIVEX CCS DINDX TCF DACLOOP CAF 13,14,15 EXTEND WOR CHAN14 # SET DAC ACTIVITY BITS TCF RETNMORE DEC -384 DACLIMIT DEC 16000 DEC 384 ONETENTH OCT 03146 # DECIMAL +0.1, SCALED AT 1. DSPLYALT EQUALS BIT4 # 100 MS ALTERNATION BIT IN RCSFLAGS OVERSUB2 TS 7 # RETURNS A UNCHANGED OR LIMITED TO TC Q # POSMAX OR NEGMAX IF A HAS OVERFLOW INDEX A # Page 1420 CS LIMITS # DUPLICATE CODING IN BANK 16 TC Q RETNMORE EXTEND # RETURN TO CHEKMORE DCA MORECADR DTCB EBANK= AOSQ MORECADR 2CADR CHEKMORE