Source Code

These source-code files derive from a printout of Luminary 116 (the Apollo 12 Lunar Module guidance computer program), from the personal library of original AGC developer Don Eyles, digitally photographed at archive.org, financially sponsored by Ron Burkey, and transcribed to source code by a team of volunteers. This colorized, syntax-highlighted form was created by assembling that transcribed source code. Note that the full page images are available on the Virtual AGC project page at archive.org, while reduced-size images are presented at the VirtualAGC project website. Report or fix any transcription errors at the Virtual AGC project code repository.

Notations on the program listing read, in part:

	GAP:  ASSEMBLE REVISION 116 OF AGC PROGRAM LUMINARY BY NASA 2021112-071
	19:09 AUG. 11,1969
Note that the date is the date of the printout, not the date of the program revision.

038498,000002:                                                                                                  ## Copyright:   Public domain.
038499,000003:                                                                                                  ## Filename:    LANDING_ANALOG_DISPLAYS.agc
038500,000004:                                                                                                  ## Purpose:     A section of Luminary revision 116.
038501,000005:                                                                                                  ##              It is part of the source code for the Lunar Module's (LM) 
038502,000006:                                                                                                  ##              Apollo Guidance Computer (AGC) for Apollo 12.
038503,000007:                                                                                                  ##              This file is intended to be a faithful transcription, except
038504,000008:                                                                                                  ##              that the code format has been changed to conform to the
038505,000009:                                                                                                  ##              requirements of the yaYUL assembler rather than the
038506,000010:                                                                                                  ##              original YUL assembler.
038507,000011:                                                                                                  ## Reference:   pp. 891-900
038508,000012:                                                                                                  ## Assembler:   yaYUL
038509,000013:                                                                                                  ## Contact:     Ron Burkey <info@sandroid.org>.
038510,000014:                                                                                                  ## Website:     www.ibiblio.org/apollo/index.html
038511,000015:                                                                                                  ## Mod history: 2017-01-22 MAS  Created from Luminary 99.
038512,000016:                                                                                                  ##              2017-02-15 NV   Updated for Luminary 116.
038513,000017:                                                                                                  ##              2017-03-13 RSB  Proofed comment text via 3-way diff vs
038514,000018:                                                                                                  ##                              Luminary 99 and 131 ... no problems found.
038515,000019: 

Page 891

038517,000021: 21,2145                                           BANK     21                                    
038518,000022: 21,2000                                           SETLOC   R10                                   
038519,000023: 21,2000                                           BANK                                           
038520,000024: 
038521,000025: 21,2145  E7,1536                                  EBANK=   UNIT/R/                               
038522,000026: 21,2145                                           COUNT*   $$/R10                                
038523,000027: 
038524,000028: 21,2145           23714        LANDISP            LXCH     PIPCTR1                               #  UPDATE TBASE2 AND PIPCTR SIMULTANEOUSLY.
038525,000029: 21,2146           40025                           CS       TIME1                                 
038526,000030: 21,2147           53055                           DXCH     TBASE2                                
038527,000031: 
038528,000032: 21,2150           40103                           CS       FLAGWRD7                              #  IS LANDING ANALOG DISPLAYS FLAG SET?
038529,000033: 21,2151           74741                           MASK     SWANDBIT                              
038530,000034: 21,2152           10000                           CCS      A                                     
038531,000035: 21,2153           13044                           TCF      DISPRSET                              #  NO.
038532,000036: 21,2154           31300                           CA       IMODES33                              #  BIT 7 = 0 (DO ALTRATE), =1 (DO ALT.)
038533,000037: 21,2155           74745                           MASK     BIT7                                  
038534,000038: 21,2156           10000                           CCS      A                                     
038535,000039: 21,2157           12231                           TCF      ALTOUT                                
038536,000040: 21,2160           02315        ALTROUT            TC       DISINDAT                              #  CHECK MODE SELECT SWITCH AND DIDFLG.
038537,000041: 21,2161           41300                           CS       IMODES33                              
038538,000042: 21,2162           74745                           MASK     BIT7                                  
038539,000043: 21,2163           27300                           ADS      IMODES33                              #  ALTERNATE ALTITUDE RATE WITH ALTITUDE.
038540,000044: 21,2164           34752                           CAF      BIT2                                  #  RATE COMMAND IS EXECUTED BEFORE RANGE.
038541,000045: 21,2165           00006                           EXTEND                                         
038542,000046: 21,2166           05014                           WOR      CHAN14                                #  ALTRATE (BIT2 = 1), ALTITUDE (BIT2 = 0).
038543,000047: 21,2167           31743        ARCOMP             CA       RUNIT                                 #  COMPUTE ALTRATE=RUNIT.VVECT M/CS *2(-6).
038544,000048: 21,2170           00006                           EXTEND                                         
038545,000049: 21,2171           71706                           MP       VVECT                                 #  MULTIPLY X-COMPONENTS.
038546,000050: 21,2172           56070                           XCH      RUPTREG1                              #  SAVE SINGLE PRECISION RESULT M/CS*2(-6).
038547,000051: 21,2173           31744                           CA       RUNIT      +1                         #  MULTIPLY Y-COMPONENTS.
038548,000052: 21,2174           00006                           EXTEND                                         
038549,000053: 21,2175           71707                           MP       VVECT      +1                         
038550,000054: 21,2176           26070                           ADS      RUPTREG1                              #  ACCUMULATE PARTIAL PRODUCTS.
038551,000055: 21,2177           31745                           CA       RUNIT      +2                         #  MULTIPLY Z-COMPONENTS.
038552,000056: 21,2200           00006                           EXTEND                                         
038553,000057: 21,2201           71710                           MP       VVECT      +2                         
038554,000058: 21,2202           26070                           ADS      RUPTREG1                              #  ALTITUDE RATE IN M/CS *2(-6).
038555,000059: 21,2203           32000                           CA       ARCONV                                #  CONVERT ALTRATE TO BIT UNITS (.5FPS/BIT)
038556,000060: 21,2204           00006                           EXTEND                                         
038557,000061: 21,2205           70070                           MP       RUPTREG1                              
038558,000062: 21,2206           20001                           DDOUBL                                         
038559,000063: 21,2207           20001                           DDOUBL                                         
038560,000064: 21,2210           56070                           XCH      RUPTREG1                              #  ALTITUDE RATE IN BIT UNITS*2(-14).
038561,000065: 21,2211           31716                           CA       DALTRATE                              #  ALTITUDE RATE COMPENSATION FACTOR.
038562,000066: 21,2212           00006                           EXTEND                                         
038563,000067: 21,2213           71715                           MP       DT                                    
038564,000068: 21,2214           60070                           AD       RUPTREG1                              
038565,000069: 21,2215           55711                           TS       ALTRATE                               #  ALTITUDE RATE IN BIT UNITS*2(-14).
038566,000070: 21,2216           41711                           CS       ALTRATE                               

Page 892

038568,000072: 21,2217           00006                           EXTEND                                         #  CHECK POLARITY OF ALTITUDE RATE.
038569,000073: 21,2220           62222                           BZMF     +2                                    
038570,000074: 21,2221           12224                           TCF      DATAOUT                               #  NEGATIVE - SEND POS. PULSES TO ALTM REG.
038571,000075: 21,2222           31711                           CA       ALTRATE                               #  POSITIVE OR ZERO - SET SIGN BIT = 1 AND
038572,000076: 21,2223           64735                           AD       BIT15                                 #  SEND TO ALTM REGISTER.  *DO NOT SEND +0*
038573,000077: 21,2224           54060        DATAOUT            TS       ALTM                                  #  ACTIVATE THE LANDING ANALOG DISPLAYS - -
038574,000078: 21,2225           34751                           CAF      BIT3                                  
038575,000079: 21,2226           00006                           EXTEND                                         
038576,000080: 21,2227           05014                           WOR      CHAN14                                #  BIT3 DRIVES THE ALT/ALTRATE METER.
038577,000081: 21,2230           15261                           TCF      TASKOVER                              #  EXIT
038578,000082: 
038579,000083: 21,2231           02315        ALTOUT             TC       DISINDAT                              #  CHECK MODE SELECT SWITCH AND DIDFLG.
038580,000084: 21,2232           44745                           CS       BIT7                                  
038581,000085: 21,2233           71300                           MASK     IMODES33                              
038582,000086: 21,2234           55300                           TS       IMODES33                              #  ALTERNATE ALTITUDE RATE WITH ALTITUDE.
038583,000087: 21,2235           44752                           CS       BIT2                                  
038584,000088: 21,2236           00006                           EXTEND                                         
038585,000089: 21,2237           03014                           WAND     CHAN14                                
038586,000090: 21,2240           11741                           CCS      ALTBITS                               #  =-1 IF OLD ALT. DATA TOBE EXTRAPOLATED.
038587,000091: 21,2241           12245                           TCF      +4                                    
038588,000092: 21,2242           12245                           TCF      +3                                    
038589,000093: 21,2243           12263                           TCF      OLDDATA                               
038590,000094: 21,2244           55741                           TS       ALTBITS                               #  SET ALTBITS FROM -0 TO +0.
038591,000095: 21,2245           44753                           CS       ONE                                   
038592,000096: 21,2246           53742                           DXCH     ALTBITS                               #  SET ALTBITS =-1 FOR SWITCH USE NEXT PASS.
038593,000097: 21,2247           53713                           DXCH     ALTSAVE                               
038594,000098: 21,2250           34742                           CA       BIT10                                 #  NEW ALTITUDE EXTRAPOLATION WITH ALTRATE.
038595,000099: 21,2251           56002                           XCH      Q                                     
038596,000100: 21,2252           22007                           LXCH     7                                     #  ZL
038597,000101: 21,2253           31715                           CA       DT                                    
038598,000102: 21,2254           00006                           EXTEND                                         
038599,000103: 21,2255           10002                           DV       Q                                     #  RESCALE DT*2(-14) TO *2(-9) TIME IN CS.
038600,000104: 21,2256           00006                           EXTEND                                         
038601,000105: 21,2257           72002                           MP       ARTOA2                                #  .0021322 *2(+8)
038602,000106: 21,2260           12264                           TCF      OLDDATA    +1                         #  RATE APPLIES FOR DT CS.
038603,000107: 
038604,000108: 21,2261           53713        ZDATA2             DXCH     ALTSAVE                               
038605,000109: 21,2262           12304                           TCF      NEWDATA                               
038606,000110: 21,2263           32001        OLDDATA            CA       ARTOA                                 #  RATE APPLIES FOR .5 SEC. (4X/SEC. CYCLE)
038607,000111: 21,2264           00006                           EXTEND                                         
038608,000112: 21,2265           71711                           MP       ALTRATE                               #  EXTRAPOLATE WITH ALTITUDE RATE.
038609,000113: 21,2266           20001                           DDOUBL                                         
038610,000114: 21,2267           61713                           AD       ALTSAVE    +1                         
038611,000115: 21,2270           55713                           TS       ALTSAVE    +1                         
038612,000116: 21,2271           34755                           CAF      ZERO                                  
038613,000117: 21,2272           27712                           ADS      ALTSAVE                               
038614,000118: 21,2273           34733                           CAF      POSMAX                                #  FORCE SIGN AGREEMENT ASSUMING A
038615,000119: 21,2274           64753                           AD       ONE                                   #  NON-NEGATIVE ALTSAVE.
038616,000120: 21,2275           61713                           AD       ALTSAVE    +1                         #  IF ALTSAVE IS NEGATIVE, ZERO ALTSAVE
038617,000121: 21,2276           55713                           TS       ALTSAVE    +1                         #  AND ALTSAVE +1 AT ZERODATA.

Page 893

038619,000123: 21,2277           34755                           CAF      ZERO                                  
038620,000124: 21,2300           64733                           AD       POSMAX                                
038621,000125: 21,2301           61712                           AD       ALTSAVE                               
038622,000126: 21,2302           55712                           TS       ALTSAVE                               #  POSSIBLY SKIP TO NEWDATA.
038623,000127: 21,2303           13041                           TCF      ZERODATA                              
038624,000128: 21,2304           11713        NEWDATA            CCS      ALTSAVE    +1                         
038625,000129: 21,2305           12311                           TCF      +4                                    
038626,000130: 21,2306           12311                           TCF      +3                                    
038627,000131: 21,2307           34755                           CAF      ZERO                                  #  SET NEGATIVE ALTSAVE +1 TO +0.
038628,000132: 21,2310           55713                           TS       ALTSAVE    +1                         
038629,000133: 21,2311           11712                           CCS      ALTSAVE                               #  PROVIDE A 15 BIT UNSIGNED OUTPUT.
038630,000134: 21,2312           34735                           CAF      BIT15                                 #  THE HI-ORDER PART IS +1 OR +0.
038631,000135: 21,2313           61713                           AD       ALTSAVE    +1                         
038632,000136: 21,2314           12224                           TCF      DATAOUT                               #  DISPATCH UNSIGNED BITS TO ALTM REG.
038633,000137: 21,2315           00006        DISINDAT           EXTEND                                         
038634,000138: 21,2316           23714                           QXCH     LADQSAVE                              #  SAVE RETURN TO ALTROUT +1 OR ALTOUT +1
038635,000139: 21,2317           34746                           CAF      BIT6                                  
038636,000140: 21,2320           00006                           EXTEND                                         #  WISHETH THE ASTRONAUT THE ANALOG
038637,000141: 21,2321           02030                           RAND     CHAN30                                #  DISPLAYS?  I.E.,
038638,000142: 21,2322           10000                           CCS      A                                     #  IS THE MODE SELECT SWITCH IN PGNCS?
038639,000143: 21,2323           13044                           TCF      DISPRSET                              #  NO.  ASTRONAUT REQUESTS NO INERTIAL DATA
038640,000144: 21,2324           40075                           CS       FLAGWRD1                              #  YES.  CHECK STATUS OF DIDFLAG.
038641,000145: 21,2325           74736                           MASK     DIDFLBIT                              
038642,000146: 21,2326           00006                           EXTEND                                         
038643,000147: 21,2327           12365                           BZF      SPEEDRUN                              #  SET.  PERFORM DATA DISPLAY SEQUENCE.
038644,000148: 21,2330           40075                           CS       FLAGWRD1                              #  RESET.  PERFORM INITIALIZATION FUNCTIONS.
038645,000149: 21,2331           74736                           MASK     DIDFLBIT                              
038646,000150: 21,2332           26075                           ADS      FLAGWRD1                              #  SET DIDFLAG.
038647,000151: 21,2333           44745                           CS       BIT7                                  
038648,000152: 21,2334           71300                           MASK     IMODES33                              #  TO DISPLAY ALTRATE FIRST AND ALT. SECOND
038649,000153: 21,2335           55300                           TS       IMODES33                              
038650,000154: 21,2336           40074                           CS       FLAGWRD0                              #  ARE WE IN DESCENT TRAJECTORY?
038651,000155: 21,2337           74752                           MASK     R10FLBIT                              
038652,000156: 21,2340           00006                           EXTEND                                         
038653,000157: 21,2341           15261                           BZF      TASKOVER                              #  NO
038654,000158: 21,2342           34744                           CAF      BIT8                                  #  YES.
038655,000159: 21,2343           00006                           EXTEND                                         
038656,000160: 21,2344           05012                           WOR      CHAN12                                #  SET DISPLAY INERTIAL DATA OUTBIT.
038657,000161: 21,2345           34755                           CAF      ZERO                                  
038658,000162: 21,2346           55702                           TS       TRAKLATV                              #  LATERAL VELOCITY MONITOR FLAG
038659,000163: 21,2347           55703                           TS       TRAKFWDV                              #  FORWARD VELOCITY MONITOR FLAG
038660,000164: 21,2350           55676                           TS       LATVMETR                              #  LATVEL MONITOR METER
038661,000165: 21,2351           55677                           TS       FORVMETR                              #  FORVEL MONITOR METER
038662,000166: 21,2352           34750                           CAF      BIT4                                  
038663,000167: 21,2353           05173                           TC       TWIDDLE                               
038664,000168: 21,2354           02356                           ADRES    INTLZE                                
038665,000169: 21,2355           15261                           TCF      TASKOVER                              
038666,000170: 21,2356           34752        INTLZE             CAF      BIT2                                  
038667,000171: 21,2357           00006                           EXTEND                                         
038668,000172: 21,2360           05012                           WOR      CHAN12                                #  ENABLE RR ERROR COUNTER.

Page 894

038670,000174: 21,2361           41300                           CS       IMODES33                              
038671,000175: 21,2362           74744                           MASK     BIT8                                  
038672,000176: 21,2363           27300                           ADS      IMODES33                              #  SET INERTIAL DATA FLAG.
038673,000177: 21,2364           15261                           TCF      TASKOVER                              
038674,000178: 
038675,000179: 21,2365           41234        SPEEDRUN           CS       PIPTIME    +1                         #  UPDATE THE VELOCITY VECTOR
038676,000180: 21,2366           60025                           AD       TIME1                                 #  COMPUTE T - TN
038677,000181: 21,2367           64736                           AD       HALF                                  #  CORRECT FOR POSSIBLE OVERFLOW OF TIME1.
038678,000182: 21,2370           64736                           AD       HALF                                  
038679,000183: 21,2371           57715                           XCH      DT                                    #  SAVE FOR LATER USE
038680,000184: 21,2372           34777                           CA       1SEC                                  
038681,000185: 21,2373           54065                           TS       ITEMP5                                #  INITIALIZE FOR DIVISION LATER
038682,000186: 21,2374           00006                           EXTEND                                         
038683,000187: 21,2375           31236                           DCA      GDT/2                                 #  COMPUTE THE X-COMPONENT OF VELOCITY.
038684,000188: 21,2376           20001                           DDOUBL                                         
038685,000189: 21,2377           20001                           DDOUBL                                         
038686,000190: 21,2400           00006                           EXTEND                                         
038687,000191: 21,2401           71715                           MP       DT                                    
038688,000192: 21,2402           00006                           EXTEND                                         
038689,000193: 21,2403           10065                           DV       ITEMP5                                
038690,000194: 21,2404           57706                           XCH      VVECT                                 #  VVECT = G(T-TN) M/CS *2(-5)
038691,000195: 21,2405           00006                           EXTEND                                         
038692,000196: 21,2406           31527                           DCA      V                                     #  M/CS *2(-7)
038693,000197: 21,2407           20001                           DDOUBL                                         #  RESCALE TO 2(-5)
038694,000198: 21,2410           20001                           DDOUBL                                         
038695,000199: 21,2411           27706                           ADS      VVECT                                 #  VVECT = VN + G(T-TN) M/CS *2(-5)
038696,000200: 21,2412           30037                           CA       PIPAX                                 #  DELV CM/SEC *2(-14)
038697,000201: 21,2413           61157                           AD       PIPATMPX                              #  IN CASE PIPAX HAS BEEN ZEROED
038698,000202: 21,2414           00006                           EXTEND                                         
038699,000203: 21,2415           72004                           MP       KPIP1(5)                              #  DELV M/CS *2(-5)
038700,000204: 21,2416           27706                           ADS      VVECT                                 #  VVECT = VN + DELV + GN(T-TN) M/CS *2(-5)
038701,000205: 21,2417           00006                           EXTEND                                         
038702,000206: 21,2420           31240                           DCA      GDT/2      +2                         #  COMPUTE THE Y-COMPONENT OF VELOCITY.
038703,000207: 21,2421           20001                           DDOUBL                                         
038704,000208: 21,2422           20001                           DDOUBL                                         
038705,000209: 21,2423           00006                           EXTEND                                         
038706,000210: 21,2424           71715                           MP       DT                                    
038707,000211: 21,2425           00006                           EXTEND                                         
038708,000212: 21,2426           10065                           DV       ITEMP5                                
038709,000213: 21,2427           57707                           XCH      VVECT      +1                         
038710,000214: 21,2430           00006                           EXTEND                                         
038711,000215: 21,2431           31531                           DCA      V          +2                         
038712,000216: 21,2432           20001                           DDOUBL                                         
038713,000217: 21,2433           20001                           DDOUBL                                         
038714,000218: 21,2434           27707                           ADS      VVECT      +1                         
038715,000219: 21,2435           30040                           CA       PIPAY                                 
038716,000220: 21,2436           61160                           AD       PIPATMPY                              
038717,000221: 21,2437           00006                           EXTEND                                         
038718,000222: 21,2440           72004                           MP       KPIP1(5)                              
038719,000223: 21,2441           27707                           ADS      VVECT      +1                         

Page 895

038721,000225: 21,2442           00006                           EXTEND                                         
038722,000226: 21,2443           31242                           DCA      GDT/2      +4                         #  COMPUTE THE Z-COMPONENT OF VELOCITY.
038723,000227: 21,2444           20001                           DDOUBL                                         
038724,000228: 21,2445           20001                           DDOUBL                                         
038725,000229: 21,2446           00006                           EXTEND                                         
038726,000230: 21,2447           71715                           MP       DT                                    
038727,000231: 21,2450           00006                           EXTEND                                         
038728,000232: 21,2451           10065                           DV       ITEMP5                                
038729,000233: 21,2452           57710                           XCH      VVECT      +2                         
038730,000234: 21,2453           00006                           EXTEND                                         
038731,000235: 21,2454           31533                           DCA      V          +4                         
038732,000236: 21,2455           20001                           DDOUBL                                         
038733,000237: 21,2456           20001                           DDOUBL                                         
038734,000238: 21,2457           27710                           ADS      VVECT      +2                         
038735,000239: 21,2460           30041                           CA       PIPAZ                                 
038736,000240: 21,2461           61161                           AD       PIPATMPZ                              
038737,000241: 21,2462           00006                           EXTEND                                         
038738,000242: 21,2463           72004                           MP       KPIP1(5)                              
038739,000243: 21,2464           27710                           ADS      VVECT      +2                         
038740,000244: 
038741,000245: 21,2465           34751                           CAF      BIT3                                  #  PAUSE 40 MS TO LET OTHER RUPTS IN.
038742,000246: 21,2466           05224                           TC       VARDELAY                              
038743,000247: 
038744,000248: 21,2467           40074                           CS       FLAGWRD0                              #  ARE WE IN DESCENT TRAJECTORY?
038745,000249: 21,2470           74752                           MASK     R10FLBIT                              
038746,000250: 21,2471           10000                           CCS      A                                     
038747,000251: 21,2472           12474                           TCF      +2                                    #  YES.
038748,000252: 21,2473           01714                           TC       LADQSAVE                              #  NO.
038749,000253: 
038750,000254: 21,2474           31733                           CA       DELVS                                 #  HI X OF VELOCITY CORRECTION TERM.
038751,000255: 21,2475           61706                           AD       VVECT                                 #  HI X OF UPDATED VELOCITY VECTOR.
038752,000256: 21,2476           54061                           TS       ITEMP1                                #  = VX - DVX M/CS*2(-5).
038753,000257: 21,2477           31735                           CA       DELVS      +2                         #     Y
038754,000258: 21,2500           61707                           AD       VVECT      +1                         #     Y
038755,000259: 21,2501           54062                           TS       ITEMP2                                #  = VY - DVY M/CS*2(-5).
038756,000260: 21,2502           31737                           CA       DELVS      +4                         #     Z
038757,000261: 21,2503           61710                           AD       VVECT      +2                         #     Z
038758,000262: 21,2504           54063                           TS       ITEMP3                                #  = VZ - DVZ M/CS*2(-5).
038759,000263: 21,2505           30061                           CA       ITEMP1                                #  COMPUTE VHY, VELOCITY DIRECTED ALONG THE
038760,000264: 21,2506           00006                           EXTEND                                         #  Y-COORDINATE.
038761,000265: 21,2507           71717                           MP       UHYP                                  #  HI X OF CROSS-RANGE HALF-UNIT VECTOR.
038762,000266: 21,2510           56070                           XCH      RUPTREG1                              
038763,000267: 21,2511           30062                           CA       ITEMP2                                
038764,000268: 21,2512           00006                           EXTEND                                         
038765,000269: 21,2513           71721                           MP       UHYP       +2                         #  Y
038766,000270: 21,2514           26070                           ADS      RUPTREG1                              #  ACCUMULATE PARTIAL PRODUCTS.
038767,000271: 21,2515           30063                           CA       ITEMP3                                
038768,000272: 21,2516           00006                           EXTEND                                         
038769,000273: 21,2517           71723                           MP       UHYP       +4                         #  Z
038770,000274: 21,2520           26070                           ADS      RUPTREG1                              

Page 896

038772,000276: 21,2521           30070                           CA       RUPTREG1                              
038773,000277: 21,2522           60000                           DOUBLE                                         
038774,000278: 21,2523           57704                           XCH      VHY                                   #  VHY=VMP.UHYP M/CS*2(-5).
038775,000279: 21,2524           30061                           CA       ITEMP1                                #  NOW COMPUTE VHZ, VELOCITY DIRECTED ALONG
038776,000280: 21,2525           00006                           EXTEND                                         #  THE Z-COORDINATE.
038777,000281: 21,2526           71725                           MP       UHZP                                  #  HI X OF DOWN-RANGE HALF-UNIT VECTOR.
038778,000282: 21,2527           56070                           XCH      RUPTREG1                              
038779,000283: 21,2530           30062                           CA       ITEMP2                                
038780,000284: 21,2531           00006                           EXTEND                                         
038781,000285: 21,2532           71727                           MP       UHZP       +2                         #  Y
038782,000286: 21,2533           26070                           ADS      RUPTREG1                              #  ACCUMULATE PARTIAL PRODUCTS.
038783,000287: 21,2534           30063                           CA       ITEMP3                                
038784,000288: 21,2535           00006                           EXTEND                                         
038785,000289: 21,2536           71731                           MP       UHZP       +4                         #  Z
038786,000290: 21,2537           26070                           ADS      RUPTREG1                              
038787,000291: 21,2540           30070                           CA       RUPTREG1                              
038788,000292: 21,2541           60000                           DOUBLE                                         
038789,000293: 21,2542           57705                           XCH      VHZ                                   #  VHZ = VMP.UHZP M/CS*2(-5).
038790,000294: 21,2543           35015        GET22/32           CAF      EBANK6                                #  GET SIN(AOG),COS(AOG) FROM GPMATRIX.
038791,000295: 21,2544           54003                           TS       EBANK                                 
038792,000296: 21,2545  E6,1417                                  EBANK=   M22                                   
038793,000297: 21,2545           31417                           CA       M22                                   
038794,000298: 21,2546           54063                           TS       ITEMP3                                
038795,000299: 21,2547           31420                           CA       M32                                   
038796,000300: 21,2550           54064                           TS       ITEMP4                                
038797,000301: 21,2551           35016                           CAF      EBANK7                                
038798,000302: 21,2552           54003                           TS       EBANK                                 
038799,000303: 21,2553  E7,1536                                  EBANK=   UNIT/R/                               
038800,000304: 21,2553           30064        LATFWDV            CA       ITEMP4                                #  COMPUTE LATERAL AND FORWARD VELOCITIES.
038801,000305: 21,2554           00006                           EXTEND                                         
038802,000306: 21,2555           71704                           MP       VHY                                   
038803,000307: 21,2556           56070                           XCH      RUPTREG1                              
038804,000308: 21,2557           30063                           CA       ITEMP3                                
038805,000309: 21,2560           00006                           EXTEND                                         
038806,000310: 21,2561           71705                           MP       VHZ                                   
038807,000311: 21,2562           26070                           ADS      RUPTREG1                              #  =VHY(COS)AOG+VHZ(SIN)AOG M/CS *2(-5)
038808,000312: 21,2563           32003                           CA       VELCONV                               #  CONVERT LATERAL VELOCITY TO BIT UNITS.
038809,000313: 21,2564           00006                           EXTEND                                         
038810,000314: 21,2565           70070                           MP       RUPTREG1                              
038811,000315: 21,2566           20001                           DDOUBL                                         
038812,000316: 21,2567           57700                           XCH      LATVEL                                #  LATERAL VELOCITY IN BIT UNITS *2(-14).
038813,000317: 21,2570           30064                           CA       ITEMP4                                #  COMPUTE FORWARD VELOCITY.
038814,000318: 21,2571           00006                           EXTEND                                         
038815,000319: 21,2572           71705                           MP       VHZ                                   
038816,000320: 21,2573           56070                           XCH      RUPTREG1                              
038817,000321: 21,2574           30063                           CA       ITEMP3                                
038818,000322: 21,2575           00006                           EXTEND                                         
038819,000323: 21,2576           71704                           MP       VHY                                   
038820,000324: 21,2577           40000                           CS       A                                     
038821,000325: 21,2600           26070                           ADS      RUPTREG1                              #  =VHZ(COS)AOG-VHY(SIN)AOG M/CS *2(-5).

Page 897

038823,000327: 21,2601           32003                           CA       VELCONV                               #  CONVERT FORWARD VELOCITY TO BIT UNITS.
038824,000328: 21,2602           00006                           EXTEND                                         
038825,000329: 21,2603           70070                           MP       RUPTREG1                              
038826,000330: 21,2604           20001                           DDOUBL                                         
038827,000331: 21,2605           57701                           XCH      FORVEL                                #  FORWARD VELOCITY IN BIT UNITS *2(-14).
038828,000332: 
038829,000333: 21,2606           42005                           CS       MAXVBITS                              #  ACC.=-199.9989 FT./SEC.
038830,000334: 21,2607           54066                           TS       ITEMP6                                #  -547 BIT UNITS (OCTAL) AT 0.5571 FPS/BIT
038831,000335: 
038832,000336: 21,2610           34753                           CAF      ONE                                   #  LOOP TWICE.
038833,000337: 21,2611           54065        VMONITOR           TS       ITEMP5                                #  FORWARD AND LATERAL VELOCITY LANDING
038834,000338: 21,2612           50065                           INDEX    ITEMP5                                #        ANALOG DISPLAYS MONITOR.
038835,000339: 21,2613           11700                           CCS      LATVEL                                
038836,000340: 21,2614           12620                           TCF      +4                                    
038837,000341: 21,2615           12721                           TCF      LVLIMITS                              
038838,000342: 21,2616           12626                           TCF      +8D                                   
038839,000343: 21,2617           12721                           TCF      LVLIMITS                              
038840,000344: 21,2620           50065                           INDEX    ITEMP5                                
038841,000345: 21,2621           41700                           CS       LATVEL                                
038842,000346: 21,2622           62005                           AD       MAXVBITS                              #  +199.9989 FT./SEC.
038843,000347: 21,2623           00006                           EXTEND                                         
038844,000348: 21,2624           62634                           BZMF     CHKLASTY                              
038845,000349: 21,2625           12721                           TCF      LVLIMITS                              
038846,000350: 21,2626           50065                           INDEX    ITEMP5                                
038847,000351: 21,2627           31700                           CA       LATVEL                                
038848,000352: 21,2630           62005                           AD       MAXVBITS                              
038849,000353: 21,2631           00006                           EXTEND                                         
038850,000354: 21,2632           62634                           BZMF     +2                                    
038851,000355: 21,2633           12721                           TCF      LVLIMITS                              
038852,000356: 21,2634           50065        CHKLASTY           INDEX    ITEMP5                                
038853,000357: 21,2635           11676                           CCS      LATVMETR                              
038854,000358: 21,2636           12642                           TCF      +4                                    
038855,000359: 21,2637           12653                           TCF      LASTOK                                
038856,000360: 21,2640           12647                           TCF      +7                                    
038857,000361: 21,2641           12653                           TCF      LASTOK                                
038858,000362: 21,2642           50065                           INDEX    ITEMP5                                
038859,000363: 21,2643           31700                           CA       LATVEL                                
038860,000364: 21,2644           00006                           EXTEND                                         
038861,000365: 21,2645           62672                           BZMF     LASTPOSY   +5                         
038862,000366: 21,2646           12653                           TCF      +5                                    
038863,000367: 21,2647           50065                           INDEX    ITEMP5                                
038864,000368: 21,2650           41700                           CS       LATVEL                                
038865,000369: 21,2651           00006                           EXTEND                                         
038866,000370: 21,2652           62707                           BZMF     LASTNEGY   +4                         
038867,000371: 21,2653           50065        LASTOK             INDEX    ITEMP5                                
038868,000372: 21,2654           11702                           CCS      TRAKLATV                              
038869,000373: 21,2655           12665                           TCF      LASTPOSY                              
038870,000374: 21,2656           12660                           TCF      +2                                    
038871,000375: 21,2657           12703                           TCF      LASTNEGY                              
038872,000376: 21,2660           50065                           INDEX    ITEMP5                                

Page 898

038874,000378: 21,2661           31700                           CA       LATVEL                                
038875,000379: 21,2662           00006                           EXTEND                                         
038876,000380: 21,2663           62711                           BZMF     NEGVMAXY                              
038877,000381: 21,2664           12674                           TCF      POSVMAXY                              
038878,000382: 21,2665           50065        LASTPOSY           INDEX    ITEMP5                                
038879,000383: 21,2666           31700                           CA       LATVEL                                
038880,000384: 21,2667           00006                           EXTEND                                         
038881,000385: 21,2670           62672                           BZMF     +2                                    
038882,000386: 21,2671           12674                           TCF      POSVMAXY                              
038883,000387: 21,2672           42005                           CS       MAXVBITS                              
038884,000388: 21,2673           13015                           TCF      ZEROLSTY                              
038885,000389: 21,2674           50065        POSVMAXY           INDEX    ITEMP5                                
038886,000390: 21,2675           41676                           CS       LATVMETR                              
038887,000391: 21,2676           62005                           AD       MAXVBITS                              
038888,000392: 21,2677           50065                           INDEX    ITEMP5                                
038889,000393: 21,2700           56072                           XCH      RUPTREG3                              
038890,000394: 21,2701           34753                           CAF      ONE                                   
038891,000395: 21,2702           13020                           TCF      ZEROLSTY   +3                         
038892,000396: 21,2703           50065        LASTNEGY           INDEX    ITEMP5                                
038893,000397: 21,2704           31700                           CA       LATVEL                                
038894,000398: 21,2705           00006                           EXTEND                                         
038895,000399: 21,2706           62711                           BZMF     NEGVMAXY                              
038896,000400: 21,2707           32005                           CA       MAXVBITS                              
038897,000401: 21,2710           13015                           TCF      ZEROLSTY                              
038898,000402: 21,2711           50065        NEGVMAXY           INDEX    ITEMP5                                
038899,000403: 21,2712           31676                           CA       LATVMETR                              
038900,000404: 21,2713           62005                           AD       MAXVBITS                              
038901,000405: 21,2714           40000                           COM                                            
038902,000406: 21,2715           50065                           INDEX    ITEMP5                                
038903,000407: 21,2716           56072                           XCH      RUPTREG3                              
038904,000408: 21,2717           44753                           CS       ONE                                   
038905,000409: 21,2720           13020                           TCF      ZEROLSTY   +3                         
038906,000410: 21,2721           50065        LVLIMITS           INDEX    ITEMP5                                
038907,000411: 21,2722           11702                           CCS      TRAKLATV                              
038908,000412: 21,2723           12752                           TCF      LATVPOS                               
038909,000413: 21,2724           12726                           TCF      +2                                    
038910,000414: 21,2725           12757                           TCF      LATVNEG                               
038911,000415: 21,2726           50065                           INDEX    ITEMP5                                
038912,000416: 21,2727           41676                           CS       LATVMETR                              
038913,000417: 21,2730           00006                           EXTEND                                         
038914,000418: 21,2731           62733                           BZMF     +2                                    
038915,000419: 21,2732           12766                           TCF      NEGLMLV                               
038916,000420: 21,2733           50065                           INDEX    ITEMP5                                
038917,000421: 21,2734           41700                           CS       LATVEL                                
038918,000422: 21,2735           00006                           EXTEND                                         
038919,000423: 21,2736           63011                           BZMF     LVMINLM                               
038920,000424: 21,2737           60066                           AD       ITEMP6                                
038921,000425: 21,2740           50065                           INDEX    ITEMP5                                
038922,000426: 21,2741           61676                           AD       LATVMETR                              
038923,000427: 21,2742           00006                           EXTEND                                         

Page 899

038925,000429: 21,2743           63011                           BZMF     LVMINLM                               
038926,000430: 21,2744           50065                           INDEX    ITEMP5                                
038927,000431: 21,2745           61700                           AD       LATVEL                                
038928,000432: 21,2746           00006                           EXTEND                                         
038929,000433: 21,2747           50065                           INDEX    ITEMP5                                
038930,000434: 21,2750           61676                           SU       LATVMETR                              
038931,000435: 21,2751           13015                           TCF      ZEROLSTY                              
038932,000436: 21,2752           50065        LATVPOS            INDEX    ITEMP5                                
038933,000437: 21,2753           41700                           CS       LATVEL                                
038934,000438: 21,2754           00006                           EXTEND                                         
038935,000439: 21,2755           63011                           BZMF     LVMINLM                               
038936,000440: 21,2756           12763                           TCF      +5                                    
038937,000441: 21,2757           50065        LATVNEG            INDEX    ITEMP5                                
038938,000442: 21,2760           31700                           CA       LATVEL                                
038939,000443: 21,2761           00006                           EXTEND                                         
038940,000444: 21,2762           63011                           BZMF     LVMINLM                               
038941,000445: 21,2763           50065                           INDEX    ITEMP5                                
038942,000446: 21,2764           41676                           CS       LATVMETR                              
038943,000447: 21,2765           13015                           TCF      ZEROLSTY                              
038944,000448: 21,2766           50065        NEGLMLV            INDEX    ITEMP5                                
038945,000449: 21,2767           31700                           CA       LATVEL                                
038946,000450: 21,2770           00006                           EXTEND                                         
038947,000451: 21,2771           63011                           BZMF     LVMINLM                               
038948,000452: 21,2772           32005                           CA       MAXVBITS                              
038949,000453: 21,2773           50065                           INDEX    ITEMP5                                
038950,000454: 21,2774           61676                           AD       LATVMETR                              
038951,000455: 21,2775           40000                           COM                                            
038952,000456: 21,2776           50065                           INDEX    ITEMP5                                
038953,000457: 21,2777           61700                           AD       LATVEL                                
038954,000458: 21,3000           00006                           EXTEND                                         
038955,000459: 21,3001           63011                           BZMF     LVMINLM                               
038956,000460: 21,3002           00006                           EXTEND                                         
038957,000461: 21,3003           50065                           INDEX    ITEMP5                                
038958,000462: 21,3004           61700                           SU       LATVEL                                
038959,000463: 21,3005           50065                           INDEX    ITEMP5                                
038960,000464: 21,3006           61676                           AD       LATVMETR                              
038961,000465: 21,3007           40000                           COM                                            
038962,000466: 21,3010           13015                           TCF      ZEROLSTY                              
038963,000467: 21,3011           50065        LVMINLM            INDEX    ITEMP5                                
038964,000468: 21,3012           41676                           CS       LATVMETR                              
038965,000469: 21,3013           50065                           INDEX    ITEMP5                                
038966,000470: 21,3014           61700                           AD       LATVEL                                
038967,000471: 21,3015           50065        ZEROLSTY           INDEX    ITEMP5                                
038968,000472: 21,3016           56072                           XCH      RUPTREG3                              
038969,000473: 21,3017           34755                           CAF      ZERO                                  
038970,000474: 21,3020           50065                           INDEX    ITEMP5                                
038971,000475: 21,3021           55702                           TS       TRAKLATV                              
038972,000476: 21,3022           50065                           INDEX    ITEMP5                                
038973,000477: 21,3023           30072                           CA       RUPTREG3                              
038974,000478: 21,3024           64754                           AD       NEG0                                  #  AVOIDS +0 DINC HARDWARE MALFUNCTION

Page 900

038976,000480: 21,3025           50065                           INDEX    ITEMP5                                
038977,000481: 21,3026           54053                           TS       CDUTCMD                               
038978,000482: 21,3027           50065                           INDEX    ITEMP5                                
038979,000483: 21,3030           30072                           CA       RUPTREG3                              
038980,000484: 21,3031           50065                           INDEX    ITEMP5                                
038981,000485: 21,3032           27676                           ADS      LATVMETR                              
038982,000486: 21,3033           10065                           CCS      ITEMP5                                #  FIRST MONITOR FORWARD THEN LATERAL VEL.
038983,000487: 21,3034           12611                           TCF      VMONITOR                              
038984,000488: 
038985,000489: 21,3035           35020                           CAF      BITSET                                #  DRIVE THE X-POINTER DISPLAY.
038986,000490: 21,3036           00006                           EXTEND                                         
038987,000491: 21,3037           05014                           WOR      CHAN14                                
038988,000492: 21,3040           01714                           TC       LADQSAVE                              #  GO TO ALTROUT +1 OR TO ALTOUT +1
038989,000493: 21,3041           34755        ZERODATA           CAF      ZERO                                  #  ZERO ALTSAVE AND ALTSAVE +1 - - -
038990,000494: 21,3042           54001                           TS       L                                     #        NO NEGATIVE ALTITUDES ALLOWED.
038991,000495: 21,3043           12261                           TCF      ZDATA2                                
038992,000496: 
038993,000497:                                                                                                  #  ************************************************************************
038994,000498: 
038995,000499: 21,3044           40074        DISPRSET           CS       FLAGWRD0                              #  ARE WE IN DESCENT TRAJECTORY?
038996,000500: 21,3045           74752                           MASK     R10FLBIT                              
038997,000501: 21,3046           00006                           EXTEND                                         
038998,000502: 21,3047           13060                           BZF      ABORTON                               #  NO.
038999,000503: 21,3050           34744                           CAF      BIT8                                  #  YES.
039000,000504: 21,3051           71300                           MASK     IMODES33                              #  CHECK IF INERTIAL DATA JUST DISPLAYED.
039001,000505: 21,3052           10000                           CCS      A                                     
039002,000506: 21,3053           34752                           CAF      BIT2                                  #  YES. DISABLE RR ERROR COUNTER
039003,000507: 21,3054           64744                           AD       BIT8                                  #  NO.  REMOVE DISPLAY INERTIAL DATA
039004,000508: 21,3055           40000                           COM                                            
039005,000509: 21,3056           00006                           EXTEND                                         
039006,000510: 21,3057           03012                           WAND     CHAN12                                
039007,000511: 21,3060           43067        ABORTON            CS       BITS8/7                               #  RESET INERTIAL DATA, INTERLEAVE FLAGS.
039008,000512: 21,3061           71300                           MASK     IMODES33                              
039009,000513: 21,3062           55300                           TS       IMODES33                              
039010,000514: 21,3063           44736                           CS       DIDFLBIT                              
039011,000515: 21,3064           70075                           MASK     FLAGWRD1                              
039012,000516: 21,3065           54075                           TS       FLAGWRD1                              #  RESET DIDFLAG.
039013,000517: 21,3066           15261                           TCF      TASKOVER                              
039014,000518: 
039015,000519:                                                                                                  #  ************************************************************************
039016,000520: 
039017,000521: 21,3067           00300        BITS8/7            OCT      00300                                 #  INERTIAL DATA AND INTERLEAVE FLAGS.
039018,000522: 21,3070     5020               BITSET             =        PRIO6                                 
039019,000523: 
039020,000524:                                                                                                  #  ************************************************************************
039021,000525: 
039022,000526: 

End of include-file LANDING_ANALOG_DISPLAYS.agc.  Parent file is MAIN.agc