388 lines
10 KiB
Plaintext
388 lines
10 KiB
Plaintext
# Copyright: Public domain.
|
|
# Filename: R60_62.agc
|
|
# Purpose: Part of the source code for Colossus 2A, AKA Comanche 055.
|
|
# It is part of the source code for the Command Module's (CM)
|
|
# Apollo Guidance Computer (AGC), for Apollo 11.
|
|
# Assembler: yaYUL
|
|
# Contact: Ron Burkey <info@sandroid.org>.
|
|
# Website: www.ibiblio.org/apollo.
|
|
# Pages: 390-398
|
|
# Mod history: 2009-05-09 RSB Adapted from the Colossus249/ file
|
|
# of the same name, using Comanche055 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 055 of AGC program Comanche by NASA
|
|
# 2021113-051. 10:28 APR. 1, 1969
|
|
#
|
|
# This AGC program shall also be referred to as
|
|
# Colossus 2A
|
|
|
|
# Page 390
|
|
BANK 34
|
|
SETLOC MANUVER
|
|
BANK
|
|
|
|
EBANK= TEMPR60
|
|
|
|
COUNT 27/R60
|
|
|
|
# CONFORMS TO GSOP CHAPTER FOUR REVISION LOGIC 09 JAN 18, 1968
|
|
|
|
R60CSM TC MAKECADR
|
|
TS TEMPR60
|
|
|
|
# INSERT PRIODSP CHECK WITH R22 (V06N49) WITH JENNINGS BRODEUR
|
|
|
|
REDOMANN CAF BIT6
|
|
MASK FLAGWRD5 # IS 3-AXIS FLAG SET
|
|
CCS A
|
|
TCF TOBALL # YES
|
|
TC INTPRET
|
|
CALL
|
|
VECPOINT # TO COMPUTE FINAL ANGLES
|
|
STORE CPHI # STORE FINAL ANGLES -- CPHI, CTHETA, CPSI
|
|
EXIT
|
|
|
|
TOBALL CAF V06N18
|
|
TC BANKCALL
|
|
CADR GOPERF2R # DISPLAY PLEASE PERFORM AUTO MANEUVER
|
|
TC R61TEST
|
|
TC REDOMANC # PROCEED
|
|
TCF ENDMANU1 # ENTER I.E., FINISHED WITH R60
|
|
|
|
TC CHKLINUS # TO CHECK FOR PRIORITY DISPLAYS
|
|
TC ENDOFJOB
|
|
|
|
REDOMANC CAF BIT6
|
|
MASK FLAGWRD5 # IS 3-AXIS FLAG SET
|
|
CCS A
|
|
TCF TOBALLC # YES
|
|
TC INTPRET
|
|
CALL
|
|
VECPOINT # TO COMPUTE FINAL ANGLES
|
|
STORE CPHI # STORE ANGLES
|
|
EXIT
|
|
|
|
TOBALLC CAF PRIO30 # IS MODE AUTO AND CTL GNC
|
|
# Page 391
|
|
EXTEND
|
|
RXOR CHAN31
|
|
MASK 13,14,15
|
|
EXTEND
|
|
BZF +2 # AUTO, NON-FLASH N18
|
|
TCF TOBALL # NOT AUTO
|
|
|
|
CAF V06N18 # STATIC UP NON-FLASHING V06 N18
|
|
TC BANKCALL
|
|
CADR GODSPR
|
|
TC CHKLINUS
|
|
|
|
STARTMNV TC BANKCALL
|
|
CADR GOMANUR
|
|
ENDMANUV TCF TOBALL # FINISHED MANEUVER.
|
|
|
|
ENDMANU1 TC DOWNFLAG # RESET 3-AXIS FLAG
|
|
ADRES 3AXISFLG # BIT 6 FLAG 5
|
|
CAE TEMPR60
|
|
TC BANKJUMP
|
|
|
|
CHKLINUS CS FLAGWRD4
|
|
MASK BIT12 # IS PRIORITY DISPLAY FLAG SET?
|
|
CCS A
|
|
TC Q # NO -- EXIT
|
|
CA Q
|
|
TS MPAC +2 # SAVE RETURN
|
|
CS THREE # OBTAIN LOCATION FOR RESTART
|
|
AD BUF2 # HOLD Q OF LAST DISPLAY
|
|
TS TBASE1
|
|
|
|
TC PHASCHNG
|
|
OCT 71 # 1.7SPOT FOR RELINUS
|
|
|
|
CAF BIT7
|
|
TC LINUS # GO SET BITS FOR PRIORITY DISPLAY
|
|
TC MPAC +2
|
|
|
|
RELINUS CAF BIT5 # IS TRACK FLAG ON
|
|
MASK FLAGWRD1
|
|
EXTEND
|
|
BZF GOREDO20 # NO
|
|
|
|
TC UPFLAG
|
|
ADRES PDSPFLAG # R60 PRIODSP FLAG
|
|
|
|
TC UPFLAG
|
|
ADRES TARG1FLG # FOR R52
|
|
|
|
CAF ZERO # RESET TO ZERO, SINCE
|
|
# Page 392
|
|
TS OPTIND # OPTIND WAS SET TO -1 BY V379
|
|
|
|
CAF PRIO14 # RESTORE ORIGINAL PRIORITY
|
|
TC PRIOCHNG
|
|
|
|
TC TBASE1
|
|
|
|
GOREDO20 TC PHASCHNG
|
|
OCT 111 # 1.11 FOR PIKUP20
|
|
|
|
TC ENDOFJOB
|
|
|
|
R61TEST CA MODREG # ARE WE IN P00. IF YES THIS MUST BE
|
|
EXTEND # VERB49 OR VERB89 SO DO ENDEXT.
|
|
BZF ENDMANU1 # RESET 3-AXIS & RETURN. USER DOES ENDEXT
|
|
CA FLAGWRD4 # ARE WE IN R61 (P20)
|
|
MASK BIT12
|
|
EXTEND
|
|
BZF GOTOP00H # NO
|
|
TC GOTOV56 # YES
|
|
|
|
BIT14+7 OCT 20100
|
|
V06N18 VN 0618
|
|
|
|
# Page 393
|
|
# PROGRAM DESCRIPTION -- VECPOINT
|
|
#
|
|
# THIS INTERPRETIVE SUBROUTINE MAY BE USED TO POINT A SPACECRAFT AXIS IN A DESIRED DIRECTION. THE AXIS
|
|
# TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN SUCCESSIVE LOCATIONS OF ERASABLE MEMORY
|
|
# BEGINNING WITH THE LOCATION CALLED SCAXIS. THE COMPONENTS OF THIS VECTOR ARE GIVEN IN SPACECRAFT COORDINATES.
|
|
# THE DIRECTION IN WHICH THIS AXIS IS TO BE POINTED MUST APPEAR AS A HALF UNIT DOUBLE PRECISION VECTOR IN
|
|
# SUCCESSIVE LOCATIONS OF ERASABLE MEMORY BEGINNING WITH THE ADDRESS CALLED POINTVSM. THE COMPONENTS OF THIS
|
|
# VECTOR ARE GIVEN IN STABLE MEMBER COORDINATES. WITH THIS INFORMTION VECPOINT COMPUTES A SET OF THREE GIMBAL
|
|
# ANGLES (2'S COMPLEMENT) CORRESPONDING TO THE CROSS-PRODUCT ROTATION BETWEEN SCAXIS AND POINTVSM AND STORES THEM
|
|
# IN T(MPAC) BEFORE RETURNING TO THE CALLER.
|
|
#
|
|
# THIS ROTATION, HOWEVER, MAY BRING THE S/C INTO GIMBAL LOCK. WHEN POINTING A VECTOR IN THE Y-Z PLANE,
|
|
# THE TRANSPONDER AXIS, OR THE AOT FOR THE LEM, THE PROGRAM WILL CORRECT THIS PROGLEM BY ROTATING THE CROSS-
|
|
# PRODUCT ATTITUDE ABOUT POINTVSM BY A FIXED AMOUNT SUFFICIENT TO ROTATE THE DESIRED S/C ATTITUDE OUT OF GIMBAL
|
|
# LOCK. IF THE AXIS TO BE POINTED IS MORE THAN 40.6 DEGREES BUT LESS THAN 60.5 DEG FROM THE +X (OR -X) AXIS,
|
|
# THE ADDITIONAL ROTATION TO AVOID GIMBAL LOCK IS 35 DEGREES. IF THE AXIS IS MORE THAN 60.5 DEGREES FROM +X (OR -X)
|
|
# THE ADDITIONAL ROTATION IS 35 DEGREES. THE GIMBAL ANGLES CORRESPONDING TO THIS ATTITUDE ARE THEN COMPUTED AND
|
|
# STORED AS 2'S COMPLEMENT ANGLES N T(MPAC) BEFORE RETURNING TO THE CALLER.
|
|
#
|
|
# WHEN POINTING THE X-AXIS, OR THE THRUST VECTOR, OR ANY VECTOR WITHIN 40.6 DEG OF THE X-AXIS, VECPOINT
|
|
# CANNOT CORRECT FOR A CROSS-PRODUCT ROTATION INTO GIMBAL LOCK. IN THIS CASE A PLATFORM REALIGNMENT WOULD BE
|
|
# REQUIRED TO POINT THE VECTOR IN THE DESIRED DIRECTION. AT PRESENT NO INDICATION IS GIVEN FOR THIS SITUATION
|
|
# EXCEPT THAT THE FINAL MIDDLE GIMBAL ANGLE IN MPAC +2 IS GREATER THAN 59 DEGREES.
|
|
#
|
|
# CALLING SEQUENCE
|
|
#
|
|
# 1) LOAD SCAXIS, POINTVSM
|
|
# 2) CALL
|
|
# VECPOINT
|
|
#
|
|
# RETURNS WITH
|
|
#
|
|
# 1) DESIRED OUTER GIMBAL ANGLE IN MPAC
|
|
# 2) DESIRED INNER GIMBAL ANGLE IN MPAC +1
|
|
# 3) DESIRED MIDDLE GIMBAL ANGLE IN MPAC +2
|
|
#
|
|
# ERASABLES USED --
|
|
#
|
|
# 1) SCAXIS 6
|
|
# 2) POINTVSM 6
|
|
# 3) MIS 18
|
|
# 4) DEL 18
|
|
# 5) COF 6
|
|
# 6) VECQTEMP 1
|
|
# 7) ALL OF VAC AREA 43
|
|
#
|
|
# TOTAL 99
|
|
|
|
SETLOC VECPT
|
|
BANK
|
|
# Page 394
|
|
EBANK= BCDU
|
|
|
|
COUNT 27/VECPT
|
|
|
|
VECPOINT STQ BOV # SAVE RETURN ADDRESS
|
|
VECQTEMP
|
|
VECLEAR # AND CLEAR OVFIND
|
|
VECLEAR AXC,2 RTB
|
|
MIS # READ THE PRESENT CDU ANGLES AND
|
|
READCDUK # STORE THEM IN PD25, 26, 27
|
|
STCALL 25D
|
|
CDUTODCM # S/C AXES TO STABLE MEMBER AXES (MIS)
|
|
VLOAD VXM
|
|
POINTVSM # RESOLVE THE POINTING DIRECTION VF INTO
|
|
MIS # INITIAL S/C AXES (VF = POINTVSM)
|
|
UNIT
|
|
STORE 28D
|
|
# PD 28 29 30 31 32 33
|
|
VXV UNIT # TAKE THE CROSS PRODUCT VF X VI
|
|
SCAXIS # WHERE VI = SCAXIS
|
|
BOV VCOMP
|
|
PICKAXIS
|
|
STODL COF # CHECK MAGNITUDE
|
|
36D # OF CROSS PRODUCT
|
|
DSU BMN # VECTOR, IF LESS
|
|
DPB-14 # THAN B-14 ASSUME
|
|
PICKAXIS # UNIT OPERATION
|
|
VLOAD DOT # INVALID.
|
|
SCAXIS
|
|
28D
|
|
SL1 ARCCOS
|
|
COMPMATX CALL # NO COMPUTE THE TRANSFORMATION FROM
|
|
DELCOMP # FINAL S/C AXES TO INITIAL S/C AXES MFI
|
|
AXC,1 AXC,2
|
|
MIS # COMPUTE THE TRANSFORMATION FROM FINAL
|
|
DEL # S/C AXES TO STABLE MEMBER AXES
|
|
CALL # MFS = MIS MFI
|
|
MXM3 # (IN PD LIST)
|
|
|
|
DLOAD ABS
|
|
6 # MFS6 = SIN(CPSI) $2
|
|
DSU BMN
|
|
SINGIMLC # = SIN(59 DEGS) $2
|
|
FINDGIMB # /CPSI/ LESS THAN 59 DEGS.
|
|
# I.E., DESIRED ATTITUDE NOT IN GIMBAL LOCK
|
|
|
|
DLOAD ABS # CHECK TO SEE IF WE ARE POINTING
|
|
SCAXIS # THE THRUST AXIS
|
|
DSU BPL
|
|
SINVEC1 # SIN 49.4 DEGS $2
|
|
# Page 395
|
|
FINDGIMB # IF SO, WE ARE TRYING TO POINT IT INTO
|
|
VLOAD # GIMBAL LOCK, ABORT COULD GO HERE
|
|
STADR
|
|
STOVL MIS +12D
|
|
STADR # STORE MFS (IN PD LIST) IN MIS
|
|
STOVL MIS +6
|
|
STADR
|
|
STOVL MIS
|
|
MIS +6 # INNER GIMBAL AXIS IN FINAL S/C AXES
|
|
BPL VCOMP # LOCATE THE IG AXIS DIRECTION CLOSEST TO
|
|
IGSAMEX # FINAL X S/C AXIS
|
|
|
|
IGSAMEX VXV BMN # FIND THE SHORTEST WAY OF ROTATING THE
|
|
SCAXIS # S/C OUT OF GIMBAL LOCK BY A ROTATION
|
|
U=SCAXIS # ABOUT +- SCAXIS, I.E., IF (IG (SGN MFS3)
|
|
# X SCAXIS . XF) LESS THAN Q, U = SCAXIS
|
|
# OTHERWISE U = -SCAXIS.
|
|
|
|
VLOAD VCOMP
|
|
SCAXIS
|
|
STCALL COF # ROTATE ABOUT -SCAXIS
|
|
CHEKAXIS
|
|
U=SCAXIS VLOAD
|
|
SCAXIS
|
|
STORE COF # ROTATE ABOUT + SCAXIS
|
|
CHEKAXIS DLOAD ABS
|
|
SCAXIS # SEE IF WE ARE POINTING THE AOT
|
|
DSU BPL
|
|
SINVEC2 # SIN 29.5 DEGS $2
|
|
PICKANG1 # IF SO, ROTATE 50 DEGS ABOUT +- SCAXIS
|
|
DLOAD GOTO # IF NOT, MUST BE POINTING THE TRANSPONDER
|
|
VECANG2 # OR SOME VECTOR IN THE Y, OR Z PLANE
|
|
COMPMFSN # IN THIS CASE ROTATE 35 DEGS TO GET OUT
|
|
# OF GIMBAL LOCK (VECANG2 $360)
|
|
PICKANG1 DLOAD
|
|
VECANG1 # = 50 DEGS. $360
|
|
COMPMFSN CALL
|
|
DELCOMP # COMPUTE THE ROTATION ABOUT SCAXIS TO
|
|
AXC,1 AXC,2 # BRING MFS OUT OF GIMBAL LOCK
|
|
MIS
|
|
DEL
|
|
CALL # COMPUTE THE NEW TRANSFORMATION FROM
|
|
MXM3 # DESIRED S/C AXES TO STABLE MEMBER AXES
|
|
# WHICH WILL ALIGN VI WITH VF AND AVOID
|
|
# GIMBAL LOCK
|
|
FINDGIMB AXC,1 CALL
|
|
0 # EXTRACT THE COMMANDED CDU ANGLES FROM
|
|
DCMTOCDU # THIS MATRIX
|
|
RTB SETPD
|
|
V1STO2S # CONVERT TO 2'S COMPLEMENT
|
|
# Page 396
|
|
0
|
|
GOTO
|
|
VECQTEMP # RETURN TO CALLER
|
|
|
|
PICKAXIS VLOAD DOT # IF VF X VI = 0, FIND VF, VI
|
|
28D
|
|
SCAXIS
|
|
BMN TLOAD
|
|
ROT180
|
|
25D
|
|
GOTO # IF VF = VI, CDU DESIRED = PRESENT CDU
|
|
VECQTEMP # PRESENT CDU ANGLES
|
|
|
|
ROT180 VLOAD VXV # IF VF, VI ANTI-PARALLEL, 180 DEG ROTATION
|
|
MIS +6 # IS REQUIRED. Y STABLE MEMBER AXIS IN
|
|
HIUNITX # INITIAL S/C AXES.
|
|
UNIT VXV # FIND Y(SM) X X(I)
|
|
SCAXIS # FIND UNIT(VI X UNIT(Y(SM) X X(I)))
|
|
UNIT BOV # I.E., PICK A VECTOR IN THE PLANE OF X(I),
|
|
PICKX # Y(SM) PERPENDICULAR TO VI
|
|
STODL COF
|
|
36D # CHECK MAGNITUDE
|
|
DSU BMN # OF THIS VECTOR.
|
|
DPB-14 # IF LESS THAN B-14,
|
|
PICKX # PICK X-AXIS.
|
|
VLOAD
|
|
COF
|
|
XROT STODL COF
|
|
HIDPHALF
|
|
GOTO
|
|
COMPMATX
|
|
PICKX VLOAD GOTO # PICK THE XAXIS IN THIS CASE
|
|
HIUNITX
|
|
XROT
|
|
BANK 35
|
|
SETLOC MANUVER1
|
|
BANK
|
|
|
|
SINGIMLC 2DEC .4285836003 # = SIN(59) $2
|
|
|
|
SINVEC1 2DEC .3796356537 # = SIN(49.4) $2
|
|
|
|
SINVEC2 2DEC .2462117800 # = SIN(29.5) $2
|
|
|
|
VECANG1 2DEC .1388888889 # = 50 DEGREES $360
|
|
|
|
VECANG2 2DEC .09722222222 # = 35 DEGREES $360
|
|
|
|
|
|
1BITDP OCT 0 # KEEP THIS BEFORE DPB(-14) ********
|
|
DPB-14 OCT 00001
|
|
# Page 397
|
|
OCT 00000
|
|
BANK 34
|
|
SETLOC MANUVER
|
|
BANK
|
|
|
|
# Page 398
|
|
# ROUTINE FOR INITIATING AUTOMATIC MANEUVER VIA KEYBOARD (V49)
|
|
|
|
EBANK= CPHI
|
|
|
|
COUNT 27/R62
|
|
|
|
R62DISP CAF V06N22 # DISPLAY COMMAND ICDUS CPHI, CTHETA, CPHI
|
|
TC BANKCALL
|
|
CADR GOFLASH
|
|
TCF ENDEXT
|
|
TCF GOMOVE # PROCEED
|
|
TCF R62DISP # ENTER
|
|
|
|
# ASTRONAUT MAY LOAD NEW ICDUS AT THIS
|
|
# POINT.
|
|
GOMOVE TC UPFLAG # SET FOR 3-AXIS MANEUVER
|
|
ADRES 3AXISFLG
|
|
|
|
TC BANKCALL
|
|
CADR R60CSM
|
|
TCF ENDEXT
|
|
|