https://github.com/chrislgarry/Apollo-11
Tip revision: 422050965990dfa8ad1ffe4ae92e793d7d1ddae5 authored by panoreak on 11 October 2020, 02:01:06 UTC
Proof INPUT_OUTPUT_CHANNEL_BIT_DESCRIPTIONS.acg #592 (#708)
Proof INPUT_OUTPUT_CHANNEL_BIT_DESCRIPTIONS.acg #592 (#708)
Tip revision: 4220509
INTERPRETER.agc
# Copyright: Public domain.
# Filename: INTERPRETER.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 <info@sandroid.org>.
# Website: www.ibiblio.org/apollo.
# Pages: 1002-1094
# Mod history: 2009-05-25 RSB Adapted from the corresponding
# Luminary131 file, using page
# images from Luminary 1A.
# 2011-01-06 JL Fixed pseudo-label indentation.
# 2011-05-08 JL Removed workarounds.
# 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 2021112-061
# 16:27 JULY 14, 1969
# Page 1002
# SECTION 1: DISPATCHER
#
# ENTRY TO THE INTERPRETER. INTPRET SETS LOC TO THE FIRST INSTRUCTION, BANKSET TO THE BBANK OF THE
# OBJECT INTERPRETIVE PROGRAM, AND INTBIT15 TO THE BIT15 CONTENTS OF FBANK. INTERPRETIVE PROGRAMS MAY BE IN
# VIRTUALLY ALL BANKS PRESENT UNDER ANY SUPER-BANK SETTING, WITH THE RESTRICTION THAT PROGRAMS IN HIGH BANKS
# (BIT15 OF FBANK = 1) DO NOT REFER TO LOWBANKS, AND VICE-VERSA. THE INTERPRETER DOES NOT SWITCH SUPERBANKS.
# E-BANK SWITCHING OCCURS WHENEVER GENERAL ERASABLE (100-3777) IS ADDRESSED.
BLOCK 03
COUNT* $$/INTER
INTPRET RELINT
EXTEND # SET LOC TO THE WORD FOLLOWING THE TC.
QXCH LOC
+2 CA BBANK # INTERPRETIVE BRANCHES FINISH HERE.
TS BANKSET
MASK BIT15 # GET 15TH BIT FOR INDEXABLE ADDRESSES.
TS INTBIT15
TS EDOP # MAKE SURE NO INSTRUCTIONS LEFT OVER
TCF NEWOPS # PICK UP OP CODE PAIR AND BEGIN.
INTRSM LXCH BBANK # RESUME SUSPENDED INTERPRETIVE JOB
TCF INTPRET +3
# DLOAD LOADS MPAC, MPAC +1, LEAVING ZERO IN MPAC +2.
DLOAD EXTEND
INDEX ADDRWD
DCA 0 # LOAD DP C(C(ADDRWD)) INT MPAC,MPAC +1
SLOAD2 DXCH MPAC
CAF ZERO # ZERO MPAC +2
# Page 1003
# AT THE END OF MOST INSTRUCTIONS, CONTROL IS GIVEN TO DANZIG TO DISPATCH THE NEXT OPERATION.
TS MPAC +2 # AND DECLARE DP MODE
NEWMODE TS MODE # PROLOGUE FOR MODE-CHANGING INSTRUCTIONS.
DANZIG CA BANKSET # SET BBANK BEFORE TESTING NEWJOB SO THAT
TS BBANK # IT MAY BE SAVED DIRECTLY BY CHANJOB.
NOIBNKSW CCS EDOP # SEE IF AN ORDER CODE IS LEFT OVER FROM
TCF OPJUMP # THE LAST PAIR RETRIEVED. IF SO, EXECUTE.
# EDOP IS SET TO ZERO ON ITS RE-EDITIING.
CCS NEWJOB # SEE IF A JOB OF HIGHER PRIORITY IS
TCF CHANG2 # PRESENT, AND IF SO, CHANGE JOBS.
INCR LOC # ADVANCE THE LOCATION COUNTER.
# ITRACE (1) REFERS TO "NEWOPS"
NEWOPS INDEX LOC # ENTRY TO BEGIN BY PICKING OP CODE PAIR.
CA 0 # MAY BE AN OPCODE PAIR OR A STORE CODE.
CCS A # TEST SIGN AND GET DABS(A).
TCF DOSTORE # PROCESS STORE CODE.
LOW7 OCT 177
TS EDOP # OP CODE PAIR. LEAVE THE OTHER IN EDOP
MASK LOW7 # WHERE CCS EDOP WILL HONOR IT NEXT.
OPJUMP TS CYR # LOWWD ENTERS HERE IF A RIGHT-HAND OP
CCS CYR # CODE IS TO BE PROCESSED. TEST PREFICES.
TCF OPJUMP2 # TEST SECOND PREFIX BIT.
TCF EXIT # +0 OP CODE IS EXIT
# Page 1004
# PROCESS ADDRESSES WHICH MAY BE DIRECT, INDEXED, OR REFERENCE THE PUSHDOWN LIST.
ADDRESS MASK BIT1 # SEE IF ADDRESS IS INDEXED. CYR CONTAINED
CCS A # 400XX, SO BIT 1 IS NOW AS IT WAS IN CYR.
TCF INDEX # FORM INDEXED ADDRESS.
DIRADRES INDEX LOC # LOOK AHEAD TO NEXT WORD TO SEE IF
OCT40001 CS 1 # ADDRESS IS GIVEN.
CCS A
TCF PUSHUP # IF NOT.
NEG4 DEC -4
INCR LOC # IF SO, TO SHOW WE PICKED UP A WORD.
TS ADDRWD
# Page 1005
# FINAL DIGESTION OF DIRECT ADDRESSES OF OP CODES WITH 01 PREFIX IS DONE HERE. IN EACH CASE, THE
# REQUIRED 12-BIT SUB-ADDRESS IS LEFT IN ADDRWD, WITH ANY REQUIRED E OR F BANK SWITCHING DONE. ADDRESSES LESS
# THAN 45D ARE TAKEN TO BE RELATIVE TO THE WORK AREA. THE OP CODE IS NOW IN BITS 1-5 OF CYR WITH BIT 14 = 1.
AD -ENDVAC # SEE IF ADDRESS RELATIVE TO WORK AREA.
CCS A
AD -ENDERAS # IF NOT, SEE IF IN GENERAL ERASABLE.
TCF IERASTST
NETZERO CA FIXLOC # IF SO, LEAVE THE MODIFIED ADDRESS IN
ADS ADDRWD # ADDRWD AND DISPATCH.
ITR15 INDEX CYR # THIS INDEX MAKES THE NEXT INSTRUCTION
7 INDJUMP -1 # TCF INDJUMP + OP, EDITING CYR.
IERASTST EXTEND
BZMF GEADDR # GO PROCESS GENERAL-ERASABLE ADDRESS.
MASK LOW10 # FIXED BANK ADDRESS. RESTORE AND ADD B15.
AD LOW10 # SWITCH BANKS AND LEAVE SUBADDRESS IN
XCH ADDRWD # ADDRWD FOR OPERAND RETRIEVAL. (THIS
AD INTBIT15 # METHOD PRECLUDES USE OF THE LAST
TS FBANK # LOCATION IN EACH FBANK.)
ITR12 INDEX CYR
7 INDJUMP -1
GEADDR MASK LOW8
AD OCT1400
XCH ADDRWD
TS EBANK
ITR10 INDEX CYR
7 INDJUMP -1
# Page 1006
# THE FOLLOWING ROUTINE PROCESSES INTERPRETIVE INDEXED ADDRESSES. AN INTERPRETER INDEX REGISTER MAY
# CONTAIN THE ADDRESS OF ANY ERASABLE REGISTER (0-42 BEING RELATIVE TO THE VAC AREA) OR ANY INTERPRETIVE PROGRAM
# BANK, OR ANY INTEGER IN THAT RANGE.
DODLOAD* CAF DLOAD* # STODL* COMES HERE TO PROCESS LOAD ADR.
TS CYR # (STOVL* ENTERS HERE).
INDEX CA FIXLOC # SET UP INDEX LOCATION.
TS INDEXLOC
INCR LOC # (ADDRESS ALWAYS GIVEN).
INDEX LOC
CS 0
CCS A # INDEX 2 IF ADDRESS STORED COMPLEMENTED.
INCR INDEXLOC
NOOP
TS ADDRWD # 14 BIT ADDRESS TO ADDRWD.
MASK HIGH4 # IF ADDRESS GREATER THAN 2K, ADD INTBIT15
EXTEND
BZF INDEX2
CA INTBIT15
ADS ADDRWD
INDEX2 INDEX INDEXLOC
CS X1
ADS ADDRWD # DO AUGMENT, IGNORING AND CORRECTING OVF.
MASK HIGH9 # SEE IF ADDRESS IS IN WORK AREA.
EXTEND
BZF INDWORK
MASK HIGH4 # SEE IF IN FIXED BANK.
EXTEND
BZF INDERASE
CA ADDRWD # IN FIXED -- SWITCH BANKS AND CREATE
TS FBANK # SUB-ADDRESS
MASK LOW10
AD 2K
TS ADDRWD
ITR11 INDEX CYR
3 INDJUMP -1
INDWORK CA FIXLOC # MAKE ADDRWD RELATIVE TO WORK AREA.
TCF ITR13 -1
INDERASE CA OCT1400
XCH ADDRWD
TS EBANK
MASK LOW8
-1 ADS ADDRWD
# Page 1007
ITR13 INDEX CYR
3 INDJUMP -1
# Page 1008
# PUSH-UP ROUTINES. WHEN NO OPERAND ADDRESS IS GIVEN, THE APPROPRIATE OPERAND IS TAKEN FROM THE PUSH-DOWN
# LIST. IN MOST CASES THE MODE OF THE RESULT (VECTOR OR SCALAR) OF THE LAST ARITHMETIC OPERATION PERFORMED
# IS THE SAME AS THE TYPE OF OPERAND DESIRED (ALL ADD/SUBTRACT ETC.). EXCEPTIONS TO THIS GENERAL RULE ARE LISTED
# BELOW (NOTE THAT IN EVERY CASE THE MODE REGISTER IS LEFT INTACT):
#
# 1. VXSC AND V/SC WANT THE OPPOSITE TYPE OF OPERAND, E.G., IF THE LAST OPERATION YIELDED A VECTOR
# RESULT, VXSC WANTS A SCALAR.
#
# 2. THE LOAD CODES SHOULD LOAD THE ACCUMULATOR INDEPENDENT OF THE RESULT OF THE LAST OPERATION. THIS
# INCLUDES VLOAD, DLOAD, TLOAD, PDDL, AND PDVL (NO PUSHUP WITH SLOAD).
#
# 3. SOME ARITHMETIC OPERATIONS REQUIRE A STANDARD TYPE OF OPERAND REGARDLESS OF THE PREVIOUS OPERATION.
# THIS INCLUDES SIGN WANTING DP AND TAD REQUIRING TP.
PUSHUP CAF OCT23 # IF THE LOW 5 BITS OF CYR ARE LESS THAN
MASK CYR # 20, THIS OP REQUIRES SPECIAL ATTENTION.
AD -OCT10 # (NO -0).
CCS A
TCF REGUP # FOR ALL CODES GREATEER THAN OCT 7.
-OCT10 OCT -10
AD NEG4 # WE NOW HAVE 7 -- OP CODE (MOD4). SEE IF
CCS A # THE OP CODE (MOD4) IS THREE (REVERSE).
INDEX A # NO -- THE MODE IS DEFINITE. PICK UP THE
CS NO.WDS
TCF REGUP +2
INDEX MODE # FOR VXSC AND V/SC WE WANT THE REQUIRED
CS REVCNT # PUSHLOC DECREMENT WITHOUT CHANGING THE
TCF REGUP +2 # MODE AT THIS TIME.
REGUP INDEX MODE # MOST ALL OP CODES PUSHUP HERE.
CS NO.WDS
+2 ADS PUSHLOC
TS ADDRWD
ITR14 INDEX CYR
7 INDJUMP -1 # (THE INDEX MAKES THIS A TCF.)
OCT 2 # REVERSE PUSHUP DECREMENT. VECTOR TAKES 2
REVCNT OCT 6 # WORDS, SCALAR TAKES 6.
OCT 6
NO.WDS OCT 2 # CONVENTIONAL DECREMENT IS 6 WORDS VECTOR
OCTAL3 OCT 3 # 2 IN DP, AND 3 IN TP.
OCT 6
# Page 1009
# TEST THE SECOND PREFIX BIT TO SEE IF THIS IS A MISCELLANEOUS OR A UNARY/SHORT SHIFT OPERATION.
OPJUMP2 CCS CYR # TEST SECOND PREFIX BIT.
TCF OPJUMP3 # TEST THIRD BIT TO SEE IF UNARY OR SHIFT
-ENDVAC DEC -45
# THE FOLLOWING ROUTINE PROCESSES ADDRESSES OF SUFFIX CLASS 10. THEY ARE BASICALLY WORK AREA ADDRESSES
# IN THE RANGE 0-52, ERASABLE ECADR CONSTANTS FROM 100-3777, AND FCADRS ABOVE THAT. ALL 15 BITS ARE AVAILABLE
# IN CONTRAST TO SUFFIX 1, IN WHICH ONLY THE LOW ORDER 14 ARE AVAILABLE.
15BITADR INCR LOC # (ENTRY HERE FROM STCALL).
INDEX LOC # PICK UP ADDRESS WORD.
CA 0
TS POLISH # WE MAY NEED A SUBADDRESS LATER.
CAF LOW7+2K # THESE INSTRUCTIONS ARE IN BANK 1.
TS FBANK
MASK CYR
ITR7 INDEX A
TCF MISCJUMP
# Page 1010
# COMPLETE THE DISPATCHING OF UNARY AND SHORT SHIFT OPERATIONS.
OPJUMP3 TS FBANK # CALL IN BANK 0 (BIT5S 11-15 OF A ARE 0.)
# ITRACE (6) REFERS TO "OPJUMP3"
CCS CYR # TEST THIRD PREFIX BIT.
INDEX A # THE DECREMENTED UNARY CODE IS IN BITS
TCF UNAJUMP # 1-4 OF A (ZERO, EXIT, HAS BEEN DETECTED)
CCS MODE # IT'S A SHORT SHIFT CODE. SEE IF PRESENT
TCF SHORTT # SCALAR OR VECTOR.
TCF SHORTT
TCF SHORTV # CALLS THE APPROPRIATE ROUTINE.
FBANKMSK EQUALS BANKMASK
LVBUF ADRES VBUF
# Page 1011
# THE FOLLOWING IS THE JUMP TABLE FOR OP CODES WHICH MAY HAVE INDEXABLE ADDRESSES OR MAY PUSH UP.
INDJUMP TCF VLOAD # 00 -- LOAD MPAC WITH A VECTOR.
TCF TAD # 01 -- TRIPLE PRECISION ADD TO MPAC.
TCF SIGN # 02 -- COMPLEMENT MPAC (V OR SC) IF X NEG.
TCF VXSC # 03 -- VECTOR TIMES SCALAR.
TCF CGOTO # 04 -- COMPUTED GO TO.
TCF TLOAD # 05 -- LOAD MPAC WITH TRIPLE PRECISION.
TCF DLOAD # 06 -- LOAD MPAC WITH A DP SCALAR.
TCF V/SC # 07 -- VECTOR DIVIDED BY A SCALAR.
TCF SLOAD # 10 -- LOAD MPACIN SINGLE PRECISION.
TCF SSP # 11 -- SET SINGLE PRECISION INTO X.
TCF PDDL # 12 -- PUSH DOWN MPAC AND RE-LOAD IN DP.
TCF MXV # 13 -- MATRIX POST-MULTIPLIED BY VECTOR.
TCF PDVL # 14 -- PUSH DOWN AND VECTOR LOAD.
TCF CCALL # 15 -- COMPUTED CALL.
TCF VXM # 16 -- MATRIX PRE-MULTIPLIED BY VECTOR.
TCF TSLC # 17 -- NORMALIZE MPAC (SCALAR ONLY).
TCF DMPR # 20 -- DP MULTIPLY AND ROUND.
TCF DDV # 21 -- DP DIVIDE BY.
TCF BDDV # 22 -- DP DIVIDE INTO.
TCF GSHIFT # 23 -- GENERAL SHIFT INSTRUCTION
TCF VAD # 24 -- VECTOR ADD.
TCF VSU # 25 -- VECTOR SUBTRACT.
TCF BVSU # 26 -- VECTOR SUBTRACT FROM.
TCF DOT # 27 -- VECTOR DOT PRODUCT.
TCF VXV # 30 -- VECTOR CROSS PRODUCT.
TCF VPROJ # 31 -- VECTOR PROJECTION.
TCF DSU # 32 -- DP SUBTRACT.
TCF BDSU # 33 -- DP SUBTRACT FROM.
TCF DAD # 34 -- DP ADD.
TCF # 35 -- AVAILABLE
TCF DMP1 # 36 -- DP MULTIPLY.
TCF SETPD # 37 -- SET PUSH DOWN POINTER (DIRECT ONLY)
# CODES 10 AND 14 MUST NOT PUSH UP. CODE 04 MAY BE USED FOR VECTOR DECLARE BEFORE PUSHUP IF DESIRED.
# Page 1012
# THE FOLLOWING JUMP TABLE APPLIES TO INDEX, BRANCH, AND MISCELLANEOUS INSTRUCTIONS.
MISCJUMP TCF AXT # 00 -- ADDRESS TO INDEX TRUE.
TCF AXC # 01 -- ADDRESS TO INDEX COMPLEMENTED.
TCF LXA # 02 -- LOAD INDEX FROM ERASABLE.
TCF LXC # 03 -- LOAD INDEX FROM COMPLEMENT OF ERAS.
TCF SXA # 04 -- STORE INDEX IN ERASABLE.
TCF XCHX # 05 -- EXCHANGE INDEX WITH ERASABLE.
TCF INCR # 06 -- INCREMENT INDEX REGISTER.
TCF TIX # 07 -- TRANSFER ON INDEX.
TCF XAD # 10 -- INDEX REGISTER ADD FROM ERASABLE.
TCF XSU # 11 -- INDEX SUBTRACT FROM ERASABLE.
TCF BZE/GOTO # 12 -- BRANCH ZERO AND GOTO
TCF BPL/BMN # 13 -- BRANCH PLUS AND BRANCH MINUS.
TCF RTB/BHIZ # 14 -- RETURN TO BASIC AND BRANCH HI ZERO.
TCF CALL/ITA # 15 -- CALL AND STORE QPRET.
TCF SW/ # 16 -- SWITCH INSTRUCTIONS AND AVAILABLE.
TCF BOV(B) # 17 -- BRANCH ON OVERFLOW TO BASIC OR INT.
# Page 1013
# THE FOLLOWING JUMP TABLE APPLIES TO UNARY INSTRUCTIONS.
COUNT* $$/INTER
BANK 0 # 00 -- EXIT -- DETECTED EARLIER.
UNAJUMP TCF SQRT # 01 -- SQUARE ROOT.
TCF SINE # 02 -- SIN.
TCF COSINE # 03 -- COS.
TCF ARCSIN # 04 -- ARC SIN.
TCF ARCCOS # 05 -- ARC COS.
TCF DSQ # 06 -- DP SQUARE.
TCF ROUND # 07 -- ROUND TO DP.
TCF COMP # 10 -- COMPLEMENT VECTOR OR SCALAR
TCF VDEF # 11 -- VECTOR DEFINE.
TCF UNIT # 12 -- UNIT VECTOR.
TCF ABVALABS # 13 -- LENGTH OF VECTOR OR MAG OF SCALAR.
TCF VSQ # 14 -- SQUARE OF LENGTH OF VECTOR.
TCF STADR # 15 -- PUSH UP ON STORE CODE.
TCF RVQ # 16 -- RETURN VIA QPRET.
TCF PUSH # 17 -- PUSH MPAC DOWN.
# Page 1014
# SECTION 2 LOAD AND STORE PACKAGE.
#
# A SET OF EIGHT STORE CODES IS PROVIDED AS THE PRIMARY METHOD OF STORING THE MULTI-PURPOSE
# ACCUMULATOR (MPAC). IF IN THE DANZIG SECTION LOC REFERS TO AN ALGEBRAICALLY POSITIVE WORD, IT IS TAKEN AS A
# STORE CODE WITH A CORRESPONDING ERASABLE ADDRESS. MOST OF THESE CODES ARE TWO ADDRESS, SPECIFYING THAT THE WORD
# FOLLOWING THE STORE CODE IS TO BE USED AS AN ADDRESS FROM WHICH TO RE-LOAD MPAC. FOUR OPTIONS ARE AVAILABLE:
#
# 1. STORE STORE MPAC. THE E ADDRESS MAY BE INDEXED.
# 2. STODL STORE MPAC AND RE-LOAD IT IN DP WITH THE NEXT ADDRESS (THE LOAD MAY BE INDEXED).
# 3. STOVL STORE MPAC AND RE-LOAD A VECTOR (AS ABOVE).
# 4. STCALL STORE AND DO A CALL (BOTH ADDRESES MUST BE DIRECT HERE).
#
# STODL AND STOVL WILL TAKE FROM THE PUSH-DOWN LIST IF NO LOAD ADDRESS IS GIVEN.
BLOCK 3
COUNT* $$/INTER
STADR CA BANKSET # THE STADR CODE (PUSHUP UP ON STORE
TS FBANK # ADDRESS) ENTERS HERE.
INCR LOC
ITR1 INDEX LOC # THE STORECODE WAS STORED COMPLEMENTED TO
CS 0 # MAKE IT LOOK LIKE AN OPCODE PAIR.
AD NEGONE # (YUL CAN'T REMOVE 1 BECAUSE OF EARLY CCS)
DOSTORE TS ADDRWD
MASK LOW11 # ENTRY FROM DISPATCHER. SAVE THE ERASABLE
XCH ADDRWD # ADDRESS AND JUMP ON THE STORE CODE NO.
MASK B12T14
EXTEND
MP BIT5 # EACH TRANSFER VECTOR ENTRY IS TWO WORDS.
INDEX A
TCF STORJUMP
# Page 1015
# STORE CODE JUMP TABLE. CALLS THE APPROPRIATE STORING ROUTINE AND EXITS TO DANZIG OR TO ADDRESS WITH
# A SUPPLIED OPERATION CODE.
#
# STORE STORE,1 AND STORE,2 RETURN TO DANZIG, THUS RESETTING THE EBANK TO ITS STATE AT INTPRET.
STORJUMP TC STORE # STORE.
TCF DANZIG # PICK UP NEW OP CODE(S).
TC STORE,1
TCF DANZIG
TC STORE,2
TCF DANZIG
TC STORE # STODL.
TCF DODLOAD
TC STORE # STODL WITH INDEXED LOAD ADDRESS.
TCF DODLOAD*
TC STORE # STOVL.
TCF DOVLOAD
TC STORE # STOVL WITH INDEXED LOAD ADDRESS.
TCF DOVLOAD*
TC STORE # STOTC.
CAF CALLCODE
TS CYR
TCF 15BITADR # GET A 15 BIT ADDRESS.
# Page 1016
# STORE CODE ADDRESS PROCESSOR.
STORE,1 INDEX FIXLOC
CS X1
TCF PRESTORE
STORE,2 INDEX FIXLOC
CS X2
PRESTORE ADS ADDRWD # RESULTANT ADDRESS IS IN ERASABLE.
STORE CS ADDRWD
AD DEC45
CCS A # DOES THE ADDRESS POINT TO THE WORK AREA?
CA FIXLOC # YES.
TCF AHEAD5
CA OCT1400 # NO. SET EBANK & MAKE UP SUBADDRESS.
XCH ADDRWD
TS EBANK
MASK LOW8
AHEAD5 ADS ADDRWD
# Page 1017
# STORING ROUTINES. STORE DP, TP, OR VECTOR AS INDICATED BY MODE.
STARTSTO EXTEND # MPAC,+1 MUST BE STORED IN ANY EVENT.
# ITRACE (5) REFERS TO "STARTSTO".
DCA MPAC
INDEX ADDRWD
DXCH 0
CCS MODE
TCF TSTORE
TC Q
VSTORE EXTEND
DCA MPAC +3
INDEX ADDRWD
DXCH 2
EXTEND
DCA MPAC +5
INDEX ADDRWD
DXCH 4
TC Q
TSTORE CA MPAC +2
INDEX ADDRWD
TS 2
TC Q
# Page 1018
# ROUTINES TO BEGIN PROCESSING OF THE SECOND ADDRES ASSOCIATED WITH ALL STORE-TYPE CODES EXCEPT STORE
# ITSELF.
DODLOAD CAF DLOADCOD
TS CYR
TCF DIRADRES # GO GET A DIRECT ADDRESS.
DOVLOAD CAF VLOADCOD
TS CYR
TCF DIRADRES
DOVLOAD* CAF VLOAD*
TCF DODLOAD* +1 # PROLOGUE TO INDEX ROUTINE.
# Page 1019
# THE FOLLOWING LOAD INSTRUCTIONS ARE PROVIDED FOR LOADING THE MULTI-PURPOSE ACCUMULATOR MPAC.
TLOAD INDEX ADDRWD
CA 2 # LOAD A TRIPLE PRECISION ARGUMENT INTO
TS MPAC +2 # THE FIRST THREE MPAC REGISTERS, WITH THE
EXTEND # CONTENTS OF THE OTHER FOUR IRRELEVANT.
INDEX ADDRWD
DCA 0
DXCH MPAC
TMODE CAF ONE
TCF NEWMODE # DECLARE TRIPLE PRECISION MODE.
SLOAD ZL # LOAD A SINGLE PRECISION NUMBER INTO
INDEX ADDRWD # MPAC, SETTING MPAC+1,2 TO ZERO. THE
CA 0 # CONTENTS OF THE REMAINING MPAC REGISTERS
TCF SLOAD2 # ARE IRRELEVANT.
VLOAD EXTEND # LOAD A DOUBLE PRECISION VECTOR INTO
INDEX ADDRWD # MPAC,+1, MPAC+3,4, AND MPAC+5,6. THE
DCA 0 # CONTENTS OF MPAC +2 ARE IRRELEVANT.
DXCH MPAC
ENDVLOAD EXTEND # PDVL COMES HERE TO FINISH UP FOR DP, TP.
INDEX ADDRWD
DCA 2
DXCH MPAC +3
+4 EXTEND # TPDVL FINISHES HERE.
INDEX ADDRWD
DCA 4
DXCH MPAC +5
VMODE CS ONE # DECLARE VECTOR MODE.
TCF NEWMODE
# Page 1020
# THE FOLLOWING INSTRUCTIONS ARE PROVIDED FOR STORING OPERANDS IN THE PUSHDOWN LIST:
# 1. PUSH PUSHDOWN AND NO LOAD.
# 2. PDDL PUSHDOWN AND DOUBLE PRECISION LOAD.
# 3. PDVL PUSHDOWN AND VECTOR LOAD.
PDDL EXTEND
INDEX ADDRWD # LOAD MPAC,+1, PUSHING THE FORMER
DCA 0 # CONTENTS DOWN.
DXCH MPAC
INDEX PUSHLOC
DXCH 0
INDEX MODE # ADVANCE THE PUSHDOWN POINTER APPRO-
CAF NO.WDS # PRIATELY.
ADS PUSHLOC
CCS MODE
TCF ENDTPUSH
TCF ENDDPUSH
TS MODE # NOW DP.
ENDVPUSH TS MPAC +2
DXCH MPAC +3 # PUSH DOWN THE REST OF THE VECTOR HERE.
INDEX PUSHLOC
DXCH 0 -4
DXCH MPAC +5
INDEX PUSHLOC
DXCH 0 -2
TCF DANZIG
ENDDPUSH TS MPAC +2 # SET MPAC +2 TO ZERO AND EXIT ON DP.
TCF DANZIG
ENDTPUSH TS MODE
XCH MPAC +2 # ON TRIPLE, SET MPAC +2 TO ZERO, PUSHING
+2 INDEX PUSHLOC # DOWN THE OLD CONTENTS
TS 0 -1
TCF DANZIG
# Page 1021
# PDVL -- PUSHDOWN AND VECTOR LOAD
PDVL EXTEND # RELOAD MPAC AND PUSH DOWN ITS CONTENTS.
INDEX ADDRWD
DCA 0
DXCH MPAC
INDEX PUSHLOC
DXCH 0
INDEX MODE # ADVANCE THE PUSHDOWN POINTER.
CAF NO.WDS
ADS PUSHLOC
CCS MODE # TEST PAST MODE.
TCF TPDVL
TCF ENDVLOAD # JUST LOAD LAST FOUR REGISTERS ON DP.
VPDVL EXTEND # PUSHDOWN AND RE-LOAD LAST TWO COMPONENTS
INDEX ADDRWD
DCA 2
DXCH MPAC +3
INDEX PUSHLOC
DXCH 0 -4
EXTEND
INDEX ADDRWD
DCA 4
DXCH MPAC +5
INDEX PUSHLOC
DXCH 0 -2
TCF DANZIG
TPDVL EXTEND # ON TP, WE MUST LOAD THE Y COMPONENT
INDEX ADDRWD # BEFORE STORING MPAC +2 IN CASE THIS IS A
DCA 2 # PUSHUP.
DXCH MPAC +3
CA MPAC +2
INDEX PUSHLOC # IN DP.
TS 0 -1
TCF ENDVLOAD +4
# SSP (STORE SINGLE PRECISION) IS EXECUTED HERE.
SSP INCR LOC # PICK UP THE WORD FOLLOWING THE GIVEN
INDEX LOC # ADDRESS AND STORE IT AT X.
CA 0
STORE1 INDEX ADDRWD # SOME INDEX AND MISCELLANEOUS OPS END
TS 0 # HERE.
# Page 1022
TCF DANZIG
# Page 1023
# SEQUENCE CHANGING AND SUBROUTINE CALLING OPTIONS.
#
# THE FOLLOWING OPERATIONS ARE AVAILABLE FOR SEQUENCING CHANGING, BRANCHING, AND CALLING SUBROUTINES:
# 1. GOTO GO TO.
# 2. CALL CALL SUBROUTINE SETTING QPRET.
# 3. CGOTO COMPUTED GO TO.
# 4. CCALL COMPUTED CALL.
# 7. BPL BRANCH IF MPAC POSITIVE OR ZERO.
# 8. BZE BRANCH IF MPAC ZERO.
# 9. BMN BRANCH IF MPAC NEGATIVE NON-ZERO.
CCALL INCR LOC # MAINTAIN LOC FOR QPRET COMPUTATION
INDEX LOC
CAF 0 # GET BASE ADDRESS OF CADR LIST.
INDEX ADDRWD
AD 0 # ADD INCREMENT.
TS FBANK # SELECT DESIRED CADR.
MASK LOW10
INDEX A
CAF 10000
TS POLISH
CALL CA BANKSET # FOR ANY OF THE CALL OPTIONS, MAKE UP THE
MASK BANKMASK # ADDRESS OF THE NEXT OP-CODE PAIR/STORE
AD BANKMASK # CODE AND LEAVE IT IN QPRET. NOTE THAT
AD LOC # BANKMASK = -(2000 - 1).
INDEX FIXLOC
TS QPRET
GOTO CA POLISH # BASIC BRANCHING SEQUENCE.
+1 MASK HIGH4
EXTEND
BZF GOTOERS # SEE IF ADDRESS POINTS TO FIXED OR ERAS.
+4 CA BANKSET # SET EBANK PART OF BBANK. NEXT, SET UP
TS BBANK # FBANK. THE COMBINATION IS PICKED UP &
CA POLISH # PUT INTO BANKSET AT INTPRET +2.
TS FBANK
MASK LOW10
AD 2K
TS LOC
TCF INTPRET +3
EBANK= 1400 # SO YUL DOESN'T CUSS THE "CA 1400" BELOW.
GOTOERS CA POLISH # THE GIVEN ADDRESS IS IN ERASABLE -- SEE
AD -ENDVAC # IF RELATIVE TO THE WORK ARA.
CCS A
CA POLISH # GENERAL ERASABLE.
TCF GOTOGE
# Page 1024
CA FIXLOC # WORK AREA.
AD POLISH
INDEX A # USE THE GIVEN ADDRESS AS THE ADDRESS OF
CA 0 # THE BRANCH ADDRESS.
TS POLISH
TCF GOTO +1 # ALLOWS ARBITRARY INDIRECTNESS LEVELS.
GOTOGE TS EBANK
MASK LOW8
INDEX A # USE THE GIVEN ADDRESS AS THE ADDRESS OF
CA 1400 # THE BRANCH ADDRESS.
TS POLISH
TCF GOTO +1
CGOTO INDEX LOC # COMPUTED GO TO. PICK UP ADDRESS OF CADR
CA 1 # LIST
INDEX ADDRWD # ADD MODIFIER.
AD 0
TS FBANK # SELECT GOTO ADDRESS
MASK LOW10
INDEX A
CA 10000
TS POLISH
TCF GOTO +1 # WITH ADDRESS IN A.
SWBRANCH CA BANKSET # SWITCH INSTRUCTIONS WHICH ELECT TO
TS FBANK # BRANCH COME HERE TO DO SO.
INDEX LOC
CA 1
TS POLISH
TCF GOTO +1
# Page 1025
# TRIPLE PRECISION BRANCHING ROUTINE. IF CALLING TC IS AT L, RETURN IS AS FOLLOWS:
# L+1 IF MPAC IS GREATER THAN ZERO.
# L+2 IF MPAC IS EQUAL TO +0 OR -0.
# L+3 IF MPAC IS LESS THAN ZERO.
BRANCH CCS MPAC
TC Q
TCF +2 # ON ZERO.
TCF NEG
CCS MPAC +1
TC Q
TCF +2
TCF NEG
CCS MPAC +2
TC Q
TCF +2
TCF NEG
Q+1 INDEX Q
TC 1
NEG INDEX Q # IF FIRST NON-ZERO REGISTER WAS NEGATIVE.
TC 2
Q+2 = NEG
# ITRACE (3) REFERS TO "EXIT".
EXIT CA BANKSET # RESTORE USER'S BANK SETTING, AND LEAVE
TS BBANK # INTERPRETIVE MODE.
INDEX LOC
TC 1
# Page 1026
# SECTION 3 -- ADD/SUBTRACT PACKAGE.
#
# THE FOLLOWING OPERATIONS ARE PROVIDED FOR ADDING TO AND SUBTRACTING FROM THE MULTI-PURPOSE ACCUMULATOR
# MPAC:
# 1. DAD DOUBLE PRECISION ADD.
# 2. DSU DOUBLE PRECISION SUBTRACT.
# 3. BDSU DOUBLE PRECISION SUBTRACT FROM.
# 4. TAD TRIPLE PRECISION ADD.
# 5. VAD VECTOR ADD.
# 6. VSU VECTOR SUBTRACT.
# 7. BVSU VECTOR SUBTRACT FROM.
# THE INTERPRETIVE OVERFLOW INDICATOR OVFIND IS SET NON-ZERO IF OVERFLOW OCCURS IN ANY OF THE ABOVE.
VSU CAF BIT15 # CHANGES 0 TO DCS.
TCF +2
VAD CAF PRIO30 # CHANGES 0 TO DCA.
ADS ADDRWD
EXTEND
INDEX ADDRWD
READ HISCALAR # DCA 2 OR DCS 2
DAS MPAC +3
EXTEND # CHECK OVERFLOW.
BZF +2
TC OVERFLWY
EXTEND
INDEX ADDRWD
READ CHAN5 # DCA 4 OR DCS 4
DAS MPAC +5
EXTEND
BZF +2
TC OVERFLWZ
EXTEND
INDEX ADDRWD
READ LCHAN # DCA 0 OR DCS 0
TCF ENDVXV
DAD EXTEND
INDEX ADDRWD
DCA 0
ENDVXV DAS MPAC # VXV FINISHES HERE.
EXTEND
BZF DANZIG
# Page 1027
SETOVF TC OVERFLOW
TCF DANZIG
# Page 1028
DSU EXTEND
INDEX ADDRWD
DCS 0
TCF ENDVXV
OVERFLWZ TS L # ENTRY FOR THIRD COMPONENT.
CAF FIVE
TCF +3
OVERFLWY TS L # ENTRY FOR SECOND COMPONENT.
CAF THREE
XCH L
OVERFLOW INDEX A # ENTRY FOR 1ST COMP OR DP (L=0).
CS LIMITS # PICK UP POSMAX OR NEGMAX.
TS BUF
EXTEND
AUG A # FORCE OVERFLOW.
INDEX L
ADS MPAC +1
TS 7
CAF ZERO
AD BUF
INDEX L
ADS MPAC
TS 7
TC Q # NO OVERFLOW EXIT.
TCF SETOVF2 # SET OVFIND AND EXIT.
BVSU EXTEND
INDEX ADDRWD
DCA 2
DXCH MPAC +3
EXTEND
DCOM
DAS MPAC +3
EXTEND
BZF +2
TC OVERFLWY
EXTEND
INDEX ADDRWD
DCA 4
DXCH MPAC +5
EXTEND
DCOM
DAS MPAC +5
EXTEND
BZF +2
TC OVERFLWZ
# Page 1029
BDSU EXTEND
INDEX ADDRWD
DCA 0
DXCH MPAC
EXTEND
DCOM
TCF ENDVXV
# Page 1030
# TRIPLE PRECISION ADD ROUTINE.
TAD EXTEND
INDEX ADDRWD
DCA 1 # ADD MINOR PARTS FIRST.
DAS MPAC +1
INDEX ADDRWD
AD 0
AD MPAC
TS MPAC
TCF DANZIG
TCF SETOVF # SET OVFIND IF SUCH OCCURS.
# Page 1031
# ARITHMETIC SUBROUTINES REQUIRED IN FIXED-FIXED.
# 1. DMPSUB DOUBLE PRECISION MULTIPLY, MULTIPLY THE CONTENTS OF MPAC,+1 BY THE DP WORD WHOSE ADDRESS
# IS IN ADDRWD AND LEAVE A TRIPLE-PRECISION RESULT IN MPAC.
# 2. ROUNDSUB ROUND THE TRIPLE PRECISION CONTENTS OF MPAC TO DOUBLE PRECISION.
# 3. DOTSUB TAKE THE DOT PRODUCT OF THE VECTOR IN MPAC AND THE VECTOR WHOSE ADDRESS IS IN ADDRWD
# AND LEAVE THE TRIPLE PRECISION RESULT IN MPAC.
# 4. POLY USING THE CONTENTS OF MPAC AS A DP ARGUMENT, EVALUATE THE POLYNOMIAL WHOSE DEGREE AND
# COEFFICIENTS IMMEDIATELY FOLLOW THE TC POLY INSTRUCTION (SEE ROUTINE FOR DETAILS).
DMP INDEX Q # BASIC SUBROUTINE FOR USE BY PINBALL, ETC
CAF 0 # ADRES OF ARGUMENT FOLLOWS TC DMP .
INCR Q
-1 TS ADDRWD # (PROLOGUE FOR SETTING ADDRWD.)
DMPSUB INDEX ADDRWD # GET MINOR PART OF OPERAND AT C(ADDRWD).
CA 1
TS MPAC +2 # THIS WORKS FOR SQUARING MPAC AS WELL.
CAF ZERO # SET MPAC +1 TO ZERO SO WE CAN ACCUMULATE
XCH MPAC +1 # THE PARTIAL PRODUCTS WITH DAS
TS MPTEMP # INSTRUCTIONS.
EXTEND
MP MPAC +2 # MINOR OF MPAC X MINOR OF C(ADDRWD).
XCH MPAC +2 # DISCARD MINOR PART OF ABOVE RESULT AND
EXTEND # FORM MAJOR OF MPAC X MINOR OF C(ADDRWD).
MP MPAC
DAS MPAC +1 # GUARANTEED NO OVERFLOW.
INDEX ADDRWD # GET MAJOR PART OF ARGUMENT AT C(ADDRWD).
CA 0
XCH MPTEMP # SAVE AND BRING OUT MINOR OF MPAC.
DMPSUB2 EXTEND
MP MPTEMP # MAJOR OF C(ADDRWD) X MINOR OF MPAC.
DAS MPAC +1 # ACCUMULATE, SETTING A TO NET OVERFLOW.
XCH MPAC # SETTING MPAC TO 0 OR +-1.
EXTEND
MP MPTEMP # MAJOR OF MPAC X MAJOR OF C(ADDRWD).
DAS MPAC # GUARANTEED NO OVERFLOW.
TC Q # 49 MCT = .573 MS. INCLUDING RETURN.
# Page 1032
# ROUND MPAC TO DOUBLE PRECISION, SETTING OVFIND ON THE RARE EVENT OF OVERFLOW.
ROUNDSUB CAF ZERO # SET MPAC +2 = 0 FOR SCALARS AND CHANGE
+1 TS MODE # MODE TO DP.
VROUND XCH MPAC +2 # BUT WE NEEDN'T TAKE THE TIME FOR VECTORS.
DOUBLE
TS L
TC Q
AD MPAC +1 # ADD ROUDING BIT IF MPAC +2 WAS GREATER
TS MPAC +1 # THAN .5 IN MAGNITUDE.
TC Q
AD MPAC # PROPAGATE INTERFLOW.
TS MPAC
TC Q
SETOVF2 TS OVFIND # (RARE).
TC Q
# Page 1033
# THE DOT PRODUCT SUBROUTINE USUALLY FORMS THE DOT PRODUCT OF THE VECTOR IN MPAC WITH A STANDARD SIX
# REGISTER VECTOR WHOSE ADDRESS IS IN ADDRWD. IN THIS CASE C(DOTINC) ARE SET TO 2. VXM, HOWEVER, SETS C(DOTINC) TO
# 6 SO THAT DOTSUB DOTS MPAC WITH A COLUMN VECTOR OF THE MATRIX IN QUESTION IN THIS CASE.
PREDOT CAF TWO # PROLOGUE TO SET DOTINC TO 2.
TS DOTINC
DOTSUB EXTEND
QXCH DOTRET # SAVE RETURN
TC DMPSUB # DOT X COMPONENTS.
DXCH MPAC +3 # POSITION Y COMPONENT OF MPAC FOR
DXCH MPAC # MULTIPLICATION WHILE SAVING RESULT IN
DXCH BUF # THREE WORD BUFFER, BUF.
CA MPAC +2
TS BUF +2
CA DOTINC # ADVANCE ADDRWD TO Y COMPONENT OF
ADS ADDRWD # OTHER ARGUMENT.
TC DMPSUB
DXCH MPAC +1 # ACCUMULATE PARTIAL PRODUCTS.
DAS BUF +1
AD MPAC
AD BUF
TS BUF
TCF +2
TS OVFIND # IF OVERFLOW OCCURS.
DXCH MPAC +5 # MULTIPLY Z COMPONENTS.
DXCH MPAC
CA DOTINC
ADS ADDRWD
TC DMPSUB
ENDDOT DXCH BUF +1 # LEAVE FINAL ACCUMULATION IN MPAC.
DAS MPAC +1
AD MPAC
AD BUF
TS MPAC
TC DOTRET
TC OVERFLOW # ON OVERFLOW HERE.
TC DOTRET
# Page 1034
# DOUBLE PRECISION POLYNOMIAL EVALUATOR
# N N-1
# THIS ROUTINE EVALUATES A X + A X + ... + A X + A LEAVING THE DP RESULT IN MPAC ON EXIT.
# N N-1 1 0
#
# THE ROUTINE HAS TWO ENTRIES
#
# 1 ENTRY THRU POWRSERS. THE COEFFICIENTS MAY BE EITHER IN FIXED OR ERASABLE E. THE CALL IS BY
# TC POWRSERS, AND THE RETURN IS TO LOC(TC POWRSERS)+1. THE ENTERING DATA MUST BE AS FOLLOWS:
#
# A SP LOC-3 # ADDRESS FOR REFERENCING COEF TABLE
# L SP N-1 # N IS THE DEGREE OF THE POWER SERIES
# MPAC DP X # ARGUMENT
# LOC-2N DP A(0)
# ...
# LOC DP A(N)
#
# 2. ENTRY THRU POLY. THE CALL TO POLY AND THE ENTERING DATA MUST BE AS FOLLOWS
#
# MPAC DP X # ARGUMENT
# LOC TC POLY
# LOC+1 SP N-1
# LOC+2 DP A(0)
# ...
# LOC+2N+2 DP A(N) # RETURN IS TO LOC+2N+4
POWRSERS EXTEND
QXCH POLYRET # RETURN ADDRESS
TS POLISH # POWER SERIES ADDRESS
LXCH POLYCNT # N-1 TO COUNTER
TCF POLYCOM # SKIP SET UP BY POLY
POLY INDEX Q
CAF 0
TS POLYCNT # N-1 TO COUNTER
DOUBLE
AD Q
TS POLISH # L(A(N))-3 TO POLISH
AD FIVE
TS POLYRET # STORE RETURN ADDRESS
POLYCOM CAF LVBUF # INCOMING X WILL BE MOVED TO VBUF, SO
TS ADDRWD # SET ADDRWD SO DMPSUB WILL MPY BY VBUF.
EXTEND
INDEX POLISH
DCA 3
# Page 1035
DXCH MPAC # LOAD A(N) INTO MPAC
DXCH VBUF # SAVING X IN VBUF
TCF POLY2
POLYLOOP TS POLYCNT # SAVE DECREMENTD LOOP COUNTER
CS TWO
ADS POLISH # REGRESS COEFFICIENT POINTER
POLY2 TC DMPSUB # MULTIPLY BY X
EXTEND
INDEX POLISH
DCA 1 # ADD IN NEXT COEFFICIENT
DAS MPAC # USER'S RESPONSIBILITY TO ASSURE NO OVFLOW
CCS POLYCNT
TCF POLYLOOP
TC POLYRET # RETURN CALLER
# Page 1036
# MISCELLANEOUS MULTI-PRECISION ROUTINES REQUIRED IN FIXED-FIXED BUT NOT USED BY THE INTERPRETER.
DPAGREE CAF ZERO # DOUBLE PRECISION ENTRY --
TS MPAC +2 # ZERO LOW-ORDER WORD
TPAGREE LXCH Q # FORCE SIGN AGREEMENT AMONG THE TRIPLE
TC BRANCH # PRECISION CONTENTS OF MPAC. RETURNING
TCF ARG+ # WITH SIGNUM OF THE INPUT IN A.
TCF ARGZERO
CS POSMAX # IF NEGATIVE.
TCF +2
ARG+ CAF POSMAX
TS Q
EXTEND
AUG A # FORMS +-1.0.
AD MPAC +2
TS MPAC +2
CAF ZERO
AD Q
AD MPAC +1
TS MPAC +1
CAF ZERO
AD Q # Q STILL HAS POSMAX OR NEGMAX IN IT.
AD MPAC
ARGZERO2 TS MPAC # ALWAYS SKIPPING UNLESS ARGZERO.
TS MPAC +1
TC L # RETURN VIA L.
ARGZERO TS MPAC +2 # SET ALL THREE MPAC REGISTERS TO ZERO.
TCF ARGZERO2
# SHORTMP MULTIPLIES THE TP CONTENTS OF MPAC BY THE SINGLE PRECISION NUMBER ARRIVING IN A.
SHORTMP TS MPTEMP
EXTEND
MP MPAC +2
TS MPAC +2
SHORTMP2 CAF ZERO # SO SUBSEQUENT DAS WILL WORK.
XCH MPAC +1
TCF DMPSUB2
# Page 1037
# DMPNSUB MULTIPLIES THE DP FRACTION ARRIVING IN MPAC BY THE SP
# INTEGER ARRIVING IN A. THE DP PRODUCT DEPARTS BOTH IN MPAC AND IN
# A AND L. NOTE THAT DMPNSUB NORMALLY INCREASES THE MAGNITUDE OF THE
# CONTENTS OF MPAC. THE CUSTOMER MUST INSURE THAT B(A) X B(MPAC,MPAC+1)
# AND B(A) X B(MPAC) ARE LESS THAN 1 IN MAGNITUDE, WHERE B, AS IS OBVIOUS,
# INDICATES THE ARRIVING CONTENTS.
DMPNSUB TS DMPNTEMP
EXTEND
MP MPAC +1
DXCH MPAC # LOW PRODUCT TO MPAC, HIGH FACTOR TO A
EXTEND
MP DMPNTEMP
CA L
ADS MPAC # COMPLETING THE PRODUCT IN MPAC
EXTEND
DCA MPAC # BRINGING THE PRODUCT INTO A AND L
TC Q
# Page 1038
# MISCELLANEOUS VECTOR OPERATIONS. INCLUDED HERE ARE THE FOLLOWING.
# 1. DOT DP VECTOR DOT PRODUCT.
# 2. VXV DP VECTOR CROSS PRODUCT.
# 3. VXSC DP VECTOR TIMES SCALAR.
# 4. V/SC DP VECTOR DIVIDED BY SCALAR.
# 5. VPROJ DP VECTOR PROJECTION. ( (MPAC.X)MPAC ).
# 6. VXM DP VECTOR POST-MULTIPLIED BY MATRIX.
# 7. MXV DP VECTOR PRE-MULTIPLIED BY MATRIX.
DOT TC PREDOT # DO THE DOT PRODUCT AND EXIT, CHANGING
DMODE CAF ZERO # THE MODE TO DP SCALAR.
TCF NEWMODE
MXV CAF TWO # SET UP MATINC AND DOTINC FOR ROW
TS MATINC # VECTORS.
TCF VXM/MXV # GO TO COMMON PORTION.
VXM CS TEN # SET MATINC AND DOTINC TO REFER TO MATRIX
TS MATINC # AS THREE COLUMN VECTORS.
CAF SIX
# Page 1039
# COMMON PORTION OF MXV AND VXM.
VXM/MXV TS DOTINC
# ITRACE (2) REFERS TO "VXM/MXV".
TC MPACVBUF # SAVE VECTOR IN MPAC FOR FURTHER USE.
TC DOTSUB # GO DOT TO GET X COMPONENT OF ANSWER.
EXTEND
DCA VBUF # MOVE MPAC VECTOR BACK INTO MPAC, SAVING
DXCH MPAC # NEW X COMPONENT IN BUF2.
DXCH BUF2
EXTEND
DCA VBUF +2
DXCH MPAC +3
EXTEND
DCA VBUF +4
DXCH MPAC +5
CA MATINC # INITIALIZE ADDRWD FOR NEXT DOT PRODUCT.
ADS ADDRWD # FORMS HAS ADDRESS OF NEXT COLUMN(ROW).
TC DOTSUB
DXCH VBUF # MORE GIVEN VECTOR BACK TO MPAC, SAVING Y
DXCH MPAC # COMPONENT OF ANSWER IN VBUF +2.
DXCH VBUF +2
DXCH MPAC +3
DXCH VBUF +4
DXCH MPAC +5
CA MATINC # FORM ADDRESS OF LAST COLUMN OR ROW.
ADS ADDRWD
TC DOTSUB
DXCH BUF2 # ANSWER NOW COMPLETE. PUT COMPONENTS INTO
DXCH MPAC # PROPER MPAC REGISTERS.
DXCH MPAC +5
DXCH VBUF +2
DXCH MPAC +3
TCF DANZIG # EXIT.
# Page 1040
# VXSC -- VECTOR TIMES SCALAR.
VXSC CCS MODE # TEST PRESENT MODE.
TCF DVXSC # SEPARATE ROUTINE WHEN SCALAR IS IN MPAC.
TCF DVXSC
VVXSC TC DMPSUB # COMPUTE X COMPONENT
TC VROUND # AND ROUND IT.
DXCH MPAC +3 # PUT Y COMPONENT INTO MPAC SAVING MPAC IN
DXCH MPAC # MPAC +3.
DXCH MPAC +3
TC DMPSUB # DO SAME FOR Y AND Z COMPONENTS.
TC VROUND
DXCH MPAC +5
DXCH MPAC
DXCH MPAC +5
TC DMPSUB
TC VROUND
VROTATEX DXCH MPAC # EXIT USED TO RESTORE MPAC AFTER THIS
DXCH MPAC +5 # TYPE OF ROTATION. CALLED BY VECTOR SHIFT
DXCH MPAC +3 # RIGHT, V/SC, ETC.
DXCH MPAC
TCF DANZIG
# Page 1041
# DP VECTOR PROJECTION ROUTINE.
VPROJ TC PREDOT # (MPAC.X)MPAC IS COMPUTED AND LEFT IN
CS FOUR # MPAC. DO DOT AND FALL INTO DVXSC.
ADS ADDRWD
# VXSC WHEN SCALAR ARRIVES IN MPAC AND VECTOR IS AT X.
DVXSC EXTEND # SAVE SCALAR IN MPAC +3 AND GET X
DCA MPAC # COMPONENT OF ANSWER.
DXCH MPAC +3
TC DMPSUB
TC VROUND
CAF TWO # ADVANCE ADDRWD TO Y COMPONENT OF X.
ADS ADDRWD
EXTEND
DCA MPAC +3 # PUT SCALAR BACK INTO MPAC AND SAVE
DXCH MPAC # X RESULT IN MPAC +5.
DXCH MPAC +5
TC DMPSUB
TC VROUND
CAF TWO
ADS ADDRWD # TO Z COMPONENT.
DXCH MPAC +3 # BRING SCALAR BACK, PUTTING Y RESULT IN
DXCH MPAC # THE PROPER PLACE.
DXCH MPAC +3
TC DMPSUB
TC VROUND
DXCH MPAC # PUT Z COMPONENT IN PROPER PLACE, ALSO
DXCH MPAC +5 # POSITIONING X.
DXCH MPAC
TCF VMODE # MODE HAS CHANGED TO VECTOR.
# Page 1042
# VECTOR CROSS PRODUCT ROUTINE CALCULATES (X M -X M ,X M -X M ,X M -X M ) WHERE M IS THE VECTOR IN
# 3 2 2 3 1 3 3 1 2 1 1 2
# MPAC AND X THE VECTOR AT THE GIVEN ADDRESS.
VXV EXTEND
DCA MPAC +5 # FORM UP M3X1, LEAVING M1 IN VBUF.
DXCH MPAC
DXCH VBUF
TC DMPSUB # BY X1.
EXTEND
DCS MPAC +3 # CALCULATE -X1M2, SAVING X1M3 IN VBUF +2.
DXCH MPAC
DXCH VBUF +2
TC DMPSUB
CAF TWO # ADVANCE ADDRWD TO X2.
ADS ADDRWD
EXTEND
DCS MPAC +5 # PREPARE TO GET -X2M3, SAVING -X1M2 IN
DXCH MPAC # MPAC +5.
DXCH MPAC +5
TC DMPSUB
EXTEND
DCA VBUF # GET X2M1, SAVING -X2M3 IN VBUF +4.
DXCH MPAC
DXCH VBUF +4
TC DMPSUB
CAF TWO # ADVANCE ADDRWD TO X3.
ADS ADDRWD
EXTEND
DCS VBUF # GET -X3M1, ADDING X2M1 TO MPAC +5 TO
DXCH MPAC # COMPLETE THE Z COMPONENT OF THE ANSWER.
DAS MPAC +5
EXTEND
BZF +2
TC OVERFLWZ
TC DMPSUB
DXCH VBUF +2 # MOVE X1M3 TO MPAC +3 SETTING UP FOR X3M2
DXCH MPAC +3 # AND ADD -X3M1 TO MPAC +3 TO COMPLETE THE
DXCH MPAC # Y COMPONENT OF THE RESULT.
DAS MPAC +3
EXTEND
BZF +2
# Page 1043
TC OVERFLWY
TC DMPSUB
DXCH VBUF +4 # GO ADD -X2M3 TO X3M2 TO COMPLETE THE X
TCF ENDVXV # COMPONENT (TAIL END OF DAD).
# THE MPACVBUF SUBROUTINE SAVES THE VECTOR IN MPAC IN VBUF WITHOUT CLOBBERING MPAC.
MPACVBUF EXTEND # CALLED BY MXV, VXM, AND UNIT.
DCA MPAC
DXCH VBUF
EXTEND
DCA MPAC +3
DXCH VBUF +2
EXTEND
DCA MPAC +5
DXCH VBUF +4
TC Q # RETURN TO CALLER.
# DOUBLE PRECISION SIGN AGREE ROUTINE. ARRIVE WITH INPUT IN A+L. OUTPUT IS IN A + L.
ALSIGNAG CCS A # TEST UPPER PART.
TCF UPPOS # IT IS POSITIVE
TC Q # ZERO
TCF UPNEG # NEGATIVE
TC Q # ZERO
UPPOS XCH L # SAVE DECREMENTED UPPER PART.
AD HALF
AD HALF
TS A # SKIPS ON OVERFLOW
TCF +2
INCR L # RESTORE UPPER TO ORIGINAL VALUE
XCH L # SWAP A + L BANCK.
TC Q
UPNEG XCH L # SAVE COMPLEMENTED + DECREMENTED UPPER PT
AD NEGMAX
AD NEGONE
TS A
TCF +2 # DON'T INCREMENT IF NO OVERFLOW.
INCR L
XCH L
COM # MAKE NEGATIVE AGAIN.
TC Q
# Page 1044
# INTERPRETIVE INSTRUCTIONS WHOSE EXECUTION CONSISTS OF PRINCIPALLY CALLING SUBROUTINES.
DMP1 TC DMPSUB # DMP INSTRUCTIONS
TCF DANZIG
DMPR TC DMPSUB
TC ROUNDSUB +1 # (C(A) = +0).
TCF DANZIG
DDV EXTEND
INDEX ADDRWD # MOVE DIVIDEND INTO BUF.
DCA 0
TCF BDDV +4
BDDV EXTEND # MOVE DIVISOR INTO MPAC SAVING MPAC, THE
INDEX ADDRWD # DIVIDEND, IN BUF.
DCA 0
DXCH MPAC
+4 DXCH BUF
CAF ZERO # DIVIDE ROUTINES IN BANK 0.
TS FBANK
TCF DDV/BDDV
SETPD CA ADDRWD # MUST SET TO WORK AREA, OR EBANK TROUBLE.
TS PUSHLOC
TCF NOIBNKSW # NO FBANK SWITCH REQUIRED.
TSLC CAF ZERO # SHIFTING ROUTINES LOCATED IN BANK 00.
TS FBANK
TCF TSLC2
GSHIFT CAF LOW7 # USED AS MASK AT GENSHIFT. THIS PROCESSES
TS FBANK # ANY SHIFT INSTRUCTION (EXCEPT TSLC) WITH
TCF GENSHIFT # AN ADDRESS (ROUTINES IN BANK 0).
# Page 1045
# THE FOLLOWING IS THE PROLOGUE TO V/SC. IF THE PRESENT MODE IS VECTOR, IT SAVES THE SCALAR AT X IN BUF
# AND CALLS THE V/SC ROUTINE IN BANK 0. IF THE PRESENT MODE IS SCALAR, IT MOVES THE VECTOR AT X INTO MPAC, SAVING
# THE SCALAR IN MPAC IN BUF BEFORE CALLING THE V/SC ROUTINE IN BANK 0.
V/SC CCS MODE
TCF DV/SC # MOVE VECTOR INTO MPAC.
TCF DV/SC
VV/SC EXTEND
INDEX ADDRWD
DCA 0
V/SC1 DXCH BUF # IN BOTH CASES, VECTOR IS NOW IN MPAC AND
CAF ZERO # SCALAR IN BUF.
TS FBANK
TCF V/SC2
DV/SC EXTEND
INDEX ADDRWD
DCA 2
DXCH MPAC +3
EXTEND
INDEX ADDRWD
DCA 4
DXCH MPAC +5
CS ONE # CHANGE MODE TO VECTOR.
TS MODE
EXTEND
INDEX ADDRWD
DCA 0
DXCH MPAC
TCF V/SC1 # FINISH PROLOGUE AT COMMON SECTION.
# Page 1046
# SIGN AND COMPLEMENT INSTRUCTIONS.
SIGN INDEX ADDRWD # CALL COMP INSTRUCTION IF WORD AT X IS
CCS 0 # NEGATIVE NON-ZERO.
TCF DANZIG
TCF +2
TCF COMP # DO THE COMPLEMENT.
INDEX ADDRWD
CCSL CCS 1
TCF DANZIG
TCF DANZIG
TCF COMP
TCF DANZIG
COMP EXTEND # COMPLEMENT DP MPAC IN EVERY CASE.
DCS MPAC
DXCH MPAC
CCS MODE # EITHER COMPLEMENT MPAC +3 OR THE REST OF
TCF DCOMP # THE VECTOR ACCUMULATOR.
TCF DCOMP
EXTEND # VECTOR COMPLEMENT.
DCS MPAC +3
DXCH MPAC +3
EXTEND
DCS MPAC +5
DXCH MPAC +5
TCF DANZIG
DCOMP CS MPAC +2
TS MPAC +2
TCF DANZIG
# Page 1047
# THE FOLLOWING SHORT SHIFT CODES REQUIRE NO ADDRESS WORD:
# 1. SR1 TO SR4 SCALAR SHIFT RIGHT.
# 2. SR1R TO SR4R SCALAR SHIFT RIGHT AND ROUND.
# 3. SL1 TO SL4 SCALAR SHIFT LEFT.
# 4. SL1R TO SL4R SCALAR SHIFT LEFT AND ROUND.
# 5. VSR1 TO VSR8 VECTOR SHIFT RIGHT (ALWAYS ROUNDS).
# 6. VSL1 TO VSL8 VECTOR SHIFT LEFT (NEVER ROUNDS).
# THE FOLLOWING CODES REQUIRE AND ADDRESS WHICH MAY BE INDEXED:*
# 1. SR SCALAR SHIFT RIGHT.
# 2. SRR SCALAR SHIFT RIGHT AND ROUND.
# 3. SL SCALAR SHIFT LEFT.
# 4. SLR SCALAR SHIFT LEFT AND ROUND.
# 5. VSR VECTOR SHIFT RIGHT.
# 6. VSL VECTOR SHIFT LEFT.
# * IF THE ADDRESS IS INDEXED, AND THE INDEX MODIFICATION RESULTS IN A NEGATIVE SHIFT COUNT, A SHIFT OF THE
# ABSOLUTE VALUE OF THE COUNT IS DONE IN THE OPPOSITE DIRECTION.
BANK 00
COUNT* $$/INTER
SHORTT CAF SIX # SCALAR SHORT SHIFTS COME HERE. THE SHIFT
MASK CYR # COUNT-1 IS NOW IN BITS 2-3 OF CYR. THE
TS SR # ROUNDING BIT IS IN BIT1 AT THIS POINT.
CCS CYR # SEE IF RIGHT OR LEFT SHIFT DESIRED.
TCF TSSL # SHIFT LEFT.
SRDDV DEC 20 # MPTEMP SETTING FOR SR BEFORE DDV.
TSSR INDEX SR # GET SHIFTING BIT.
CAF BIT14
TS MPTEMP
CCS CYR # SEE IF A ROUND IS DESIRED.
RIGHTR TC MPACSRND # YES -- SHIFT RIGHT AND ROUND.
TCF NEWMODE # SET MODE TO DP (C(A) = 0).
MPACSHR CA MPTEMP # DO A TRIPLE PRECISION SHIFT RIGHT.
EXTEND
MP MPAC +2
+3 TS MPAC +2 # (EXIT FROM SQRT AND ABVAL).
CA MPTEMP
EXTEND
MP MPAC # SHIFT MAJOR PART INTO A,L AND PLACE IN
# Page 1048
DXCH MPAC # MPAC,+1.
CA MPTEMP
EXTEND
MP L # ORIGINAL C(MPAC +1).
DAS MPAC +1 # GUARANTEED NO OVERFLOW.
TCF DANZIG
# MPAC SHIFT RIGHT AND ROUND SUBROUTINES
MPACSRND CA MPAC +2 # WE HAVE TO DO ALL THREE MULTIPLIES SINCE
EXTEND # MPAC +1 AND MPAC +2 MIGHT HAVE SIGN
MP MPTEMP # DISAGREEMENT WITH A SHIFT RIGHT OF L.
XCH MPAC +1
EXTEND
MP MPTEMP
XCH MPAC +1 # TRIAL MINOR PART.
AD L
VSHR2 DOUBLE # (FINISH VECTOR COMPONENT SHIFT RIGHT
TS MPAC +2 # AND ROUND.)
TCF +2
ADS MPAC +1 # GUARANTEED NO OVERFLOW.
CAF ZERO
TS MPAC +2
XCH MPAC # SETTING TO ZERO SO FOLLOWING DAS WORKS.
EXTEND
MP MPTEMP
DAS MPAC # AGAIN NO OVERFLOW.
TC Q
VSHRRND CA MPTEMP # ENTRY TO SHIFT RIGHT AND ROUND MPAC WHEN
EXTEND # MPAC CONTAINS A VECTOR COMPONENT.
MP MPAC +1
TS MPAC +1
XCH L
TCF VSHR2 # GO ADD ONE IF NECESSARY AND FINISH.
# Page 1049
# ROUTINE FOR SHORT SCALAR SHIFT LEFT (AND MAYBE ROUND).
TSSL CA SR # GET SHIFT COUNT FOR SR.
+1 TS MPTEMP
+2 EXTEND # ENTRY HERE FROM SL FOR SCALARS.
DCA MPAC +1 # SHIFTING LEFT ONE PLACE AT A TIME IS
DAS MPAC +1 # FASTER THAN DOING THE WHOLE SHIFT WITH
AD MPAC # MULTIPLIES ASSUMING THAT FREQUENCY OF
AD MPAC # SHIFT COUNTS GOES DOWN RAPIDLY AS A
TS MPAC # FUNCTION OF THEIR MAGNITUDE.
TCF +2
TS OVFIND # OVERFLOW. (LEAVES OVERFLOW-CORRECTED
# RESULT ANYWAY).
CCS MPTEMP # LOOP ON DECREMENTED SHIFT COUNT.
TCF TSSL +1
CCS CYR # SEE IF ROUND WANTED.
ROUND TC ROUNDSUB # YES -- ROUND AND EXIT.
TCF DANZIG # SL LEAVES A ZERO IN CYR FOR NO ROUND.
TCF DANZIG # NO -- EXIT IMMEDIATELY
# Page 1050
# VECTOR SHIFTING ROUTINES.
SHORTV CAF LOW3 # SAVE 3 BIT SHIFT COUNT -- 1 WITHOUT
MASK CYR # EDITING CYR.
TS MPTEMP
CCS CYR # SEE IF LEFT OR RIGHT SHIFT.
TCF VSSL # VECTOR SHIFT LEFT.
OCT176 OCT 176 # USED IN PROCESSED SHIFTS WITH - COUNT.
VSSR INDEX MPTEMP # (ENTRY FROM SR). PICK UP SHIFTING BIT.
CAF BIT14 # MPTEMP CONTAINS THE SHIFT COUNT - 1.
TS MPTEMP
TC VSHRRND # SHIFT X COMPONENT.
DXCH MPAC # SWAP X AND Y COMPONENTS.
DXCH MPAC +3
DXCH MPAC
TC VSHRRND # SHIFT Y COMPONENT.
DXCH MPAC # SWAP Y AND Z COMPONENTS.
DXCH MPAC +5
DXCH MPAC
TC VSHRRND # SHIFT Z COMPONENT.
TCF VROTATEX # RESTORE COMPONENTS TO PROPER PLACES.
# Page 1051
# VECTOR SHIFT LEFT -- DONE ONE PLACE AT A TIME.
-1 TS MPTEMP # SHIFTING LOOP.
VSSL EXTEND
DCA MPAC
DAS MPAC
EXTEND
BZF +2
TC OVERFLOW
EXTEND
DCA MPAC +3
DAS MPAC +3
EXTEND
BZF +2
TC OVERFLWY
EXTEND
DCA MPAC +5
DAS MPAC +5
EXTEND
BZF +2
TC OVERFLWZ
CCS MPTEMP # LOOP ON DECREMENTED SHIFT COUNTER.
TCF VSSL -1
TCF DANZIG # EXIT.
# Page 1052
# TSLC -- TRIPLE SHIFT LEFT AND COUNT. SHIFTS MPAC LEFT UNTIL GREATER THAN .5 IN MAGNITUDE, LEAVING
# THE COMPLEMENT OF THE NUMBER OF SHIFTS REQUIRED IN X.
TSLC2 TS MPTEMP # START BY ZEROING SHIFT COUNT (IN A NOW).
TC BRANCH # EXIT WITH NO SHIFTING IF ARGUMENT ZERO.
TCF +2
TCF ENDTSLC # STORES ZERO SHIFT COUNT IN THIS CASE.
TC TPAGREE # MAY CAUSE UPSHIFT OF ONE EXTRA PLACE.
CA MPAC # BEGIN NORMALIZATION LOOP.
TCF TSLCTEST
TSLCLOOP INCR MPTEMP # INCREMENT SHIFT COUNTER.
EXTEND
DCA MPAC +1
DAS MPAC +1
AD MPAC
ADS MPAC
TSLCTEST DOUBLE # SEE IF (ANOTHER) SHIFT IS REQUIRED
OVSK
TCF TSLCLOOP # YES -- INCREMENT COUNT AND SHIFT AGAIN.
ENDTSLC CS MPTEMP
TCF STORE1 # STORE SHIFT COUNT AND RETURN TO DANZIG.
# Page 1053
# THE FOLLOWING ROUTINE PROCESSES THE GENERAL SHIFT INSTRUCTIONS SR, SRR, SL, AND SLR.
# THE GIVEN ADDRESS IS DECODED AS FOLLOWS:
# BITS 1-7 SHIFT COUNT (SUBADDRESS) LESS THAN 125 DECIMAL.
# BIT 8 PSEUDO SIGN BIT (DETECTS CHANGE IN SIGN IN INDEXED SHIFTS).
# BIT 9 0 FOR LEFT SHIFT, AND 1 FOR RIGHT SHIFT.
# BIT 10 1 FOR TERMINAL ROUND ON SCALAR SHIFTS, 0 OTHERWISE
# BITS 11-13 0.
# BIT 14 1.
# BIT 15 0.
# THE ABOVE ENCODING IS DONE BY THE YUL SYSTEM.
GENSHIFT MASK ADDRWD # GET SHIFT COUNT, TESTING FOR ZERO.
CCS A # (ARRIVES WITH C(A) = LOW7).
TCF GENSHFT2 # IF NON-ZERO, PROCEED WITH DECREMENTED CT
CAF BIT10 # ZERO SHIFT COUNT. NO SHIFTS NEEDED BUT
MASK ADDRWD # WE MIGHT HAVE TO ROUND MPAC ON SLR AND
CCS A # SRR (SCALAR ONLY).
TC ROUNDSUB
TCF DANZIG
GENSHFT2 TS MPTEMP # DECREMENTED SHIFT COUNT TO MPTEMP.
CAF BIT8 # TEST MEANING OF LOW SEVEN BIT COUNT IN
EXTEND # MPTEMP NOW.
MP ADDRWD
MASK LOW2 # JUMPS ON SHIFT DIRECTION (BIT8) AND
INDEX A
TCF +1 # ORIGINAL SHIFT DIRECTION (BIT 9)
TCF RIGHT- # NEGATIVE SHIFT COUNT FOR SL OR SLR.
TCF LEFT # SL OR SLR.
TCF LEFT- # NEGATIVE SHIFT COUNT WITH SR OR SRR.
# Page 1054
# GENERAL SHIFT RIGHT
RIGHT CCS MODE # SET IF VECTOR OR SCALAR.
TCF GENSCR
TCF GENSCR
CA MPTEMP # SEE IF SHIFT COUNT LESS THAN 14D.
VRIGHT2 AD NEG12
EXTEND
BZMF VSSR # IF SO, BRANCH AND SHIFT IMMEDIATELY.
AD NEGONE # IF NOT, REDUCE MPTEMP BY A TOTAL OF 14.
TS MPTEMP # AND DO A SHIFT RIGHT AND ROUND BY 14.
CAF ZERO # THE ROUND AT THIS STAGE MAY INTRODUCE A
TS L # ONE BIT ERROR IN A SHIFT RIGHT 15D.
XCH MPAC
XCH MPAC +1
TC SETROUND # X COMPONENT NOW SHIFTED, SO MAKE UP THE
DAS MPAC # ROUNDING QUANTITY (0 IN A AND 0 OR +-1
# IN L).
XCH MPAC +3 # REPEAT THE ABOVE PROCESS FOR Y AND Z.
XCH MPAC +4
TC SETROUND
DAS MPAC +3 # NO OVERFLOW ON THESE ADDS.
XCH MPAC +5
XCH MPAC +6
TC SETROUND
DAS MPAC +5
CCS MPTEMP # SEE IF DONE, DOING FINAL DECREMENT.
TS MPTEMP
TCF VRIGHT2
BIASLO DEC .2974 B-1 # SQRT CONSTANT
TCF DANZIG
SETROUND DOUBLE # MAKES UP ROUNDING QUANTITY FROM ARRIVING
TS MPAC +2 # C(A). L IS ZERO INITIALLY.
CAF ZERO
XCH L
TC Q # RETURN AND DO THE DAS, RESETTING L TO 0.
# Page 1055
# PROCESS SR AND SRR FOR SCALARS.
GENSCR CA MPTEMP # SEE IF THE ORIGINAL SHIFT COUNT WAS LESS
+1 AD NEG12 # THAN 14D.
EXTEND
BZMF DOSSHFT # DO THE SHIFT IMMEDIATELY IF SO.
+4 AD NEGONE # IF NOT, DECREMENT SHIFT COUNT BY 14D AND
TS MPTEMP # SHIFT MPAC RIGHT 14 PLACES.
CAF ZERO
XCH MPAC
XCH MPAC +1
TS MPAC +2
CCS MPTEMP # SEE IF FINISHED, DO FINAL DECREMENT.
TS MPTEMP
TC GENSCR +1
SLOPEHI DEC .5884 # SQRT CONSTANT.
CAF BIT10 # FINISHED WITH SHIFT. SEE IF ROUND
MASK ADDRWD # WANTED.
CCS A
TC ROUNDSUB
TCF DANZIG # DO SO AND/OR EXIT.
DOSSHFT INDEX MPTEMP # PICK UP SHIFTING BIT.
CAF BIT14
TS MPTEMP
CAF BIT10 # SEE IF TERMINAL ROUND DESIRED.
MASK ADDRWD
CCS A
TCF RIGHTR # YES.
TCF MPACSHR # JUST SHIFT RIGHT.
# Page 1056
# PROCESS THE RIGHT- (SL(R) WITH A NEGATIVE COUNT), LEFT-, AND LEFT OPTIONS.
RIGHT- CS MPTEMP # GET ABSOLUTE VALUE - 1 OF SHIFT COUNT
AD OCT176 # UNDERSTANDING THAT BIT8 (PSEUDO-SIGN)
TS MPTEMP # WAS 1 INITIALLY.
TCF RIGHT # DO NORMAL SHIFT RIGHT.
LEFT- CS OCT176 # SAME PROLOGUE TO LEFT FOR INDEXED RIGHT
AD MPTEMP # SHIFT WHOSE NET SHIFT COUNT IS NEGATIVE
COM
TS MPTEMP
LEFT CCS MODE # SINCE LEFT SHIFTING IS DONE ONE PLACE AT
TCF GENSCL # A TIME, NO COMPARISON WITH 14 NEED BE
TCF GENSCL # DONE. FOR SCALARS, SEE IF TERMINAL ROUND
TCF VSSL # DESIRED. FOR VECTORS, SHIFT IMMEDIATELY.
GENSCL CS ADDRWD # PUT ROUNDING BIT (BIT 10 OF ADDRWD) INTO
EXTEND # BIT 15 OF CYR WHERE THE ROUNDING BIT OF
MP BIT6 # A SHORT SHIFT LEFT WOULD BE
TS CYR
TCF TSSL +2 # DO THE SHIFT.
# Page 1057
# SCALAR DIVISION INSTRUCTIONS, DDV AND BDDV, ARE EXECUTED HERE. AT THIS POINT, THE DIVIDEND IS IN MPAC
# AND THE DIVISOR IS IN BUF.
DDV/BDDV CS ONE # INITIALIZATION
TS DVSIGN # +-1 FOR POSITIVE QUOTIENT -- -0 FOR NEG.
TS DVNORMCT # DIVIDENT NORMALIZATION COUNT.
TS MAXDVSW # NEAR-ONE DIVIDE FLAG.
CCS BUF # FORCE BUF POSITIVE WITH THE MAJOR PART
TCF BUFPOS # NON-ZERO.
TCF +2
TCF BUFNEG
BUFZERO TS MPAC +2 # ZERO THIS.
TC TPAGREE # FORCE SIGN AGREEMENT BEFORE OVERFLOW
CCS MPAC # TEST TO SEE IF MPAC NON-ZERO. (TOO BIG)
TCF OVF+ # MAJOR PART OF DIVIDEND IS POSITIVE NON-0
TCF +2
TCF OVF+ -1 # MAJOR PART OF DIVIDEND IS NEG. NON-ZERO
XCH BUF +1 # SHIFT DIVIDEND AND DIVISOR LEFT 14
XCH BUF
XCH MPAC +1
XCH MPAC
CCS BUF # TRY AGAIN ON FORMER MINOR PART.
TCF BUF+
TCF +2 # OVERFLOW ON ZERO DIVISOR.
TCF BUF-
CS MPAC # SIGN OF MPAC DETERMINES SIGN OF RESULT.
SGNDVOVF EXTEND
BZMF +2
INCR DVSIGN # NEGMAX IN MPAC PERHAPS.
DVOVF CAF POSMAX # ON DIVISION OVERFLOW OF ANY SORT, SET
TS MPAC # SET DP MPAC TO +-POSMAX.
TC FINALDV +3
CAF ONE # SET OVERFLOW INDICATOR AND EXIT.
TS OVFIND
TC DANZIG
-1 INCR DVSIGN
OVF+ CS BUF +1 # LOAD LOWER ORDER PART OF DIVISOR.
TCF SGNDVOVF # GET SIGN OF RESULT.
BUF- EXTEND # IF BUF IS NEGATIVE, COMPLEMENT IT AND
DCS BUF # MAINTAIN DVSIGN FOR FINAL QUOTIENT SIGN.
DXCH BUF
INCR DVSIGN # NOW -0.
# Page 1058
BUF+ CCS MPAC # FORCE MPAC POSITIVE, CHECKING FOR ZERO
TCF MPAC+ # DIVIDEND IN THE PROCESS.
TCF +2
TCF MPAC-
CCS MPAC +1
TCF MPAC+
TCF DANZIG # EXIT IMMEDIATELY ON ZERO DIVIDEND.
TCF MPAC-
TCF DANZIG
MPAC- EXTEND # FORCE MPAC POSITIVE AS BUF IN BUF-.
DCS MPAC
DXCH MPAC
INCR DVSIGN # NOW +1 OR -0.
# Page 1059
MPAC+ CS MPAC # CHECK FOR DIVISION OVERFLOW. IF THE
AD NEGONE # MAJOR PART OF THE DIVIDEND IS LESS THAN
AD BUF # THE MAJOR PART OF THE DIVISOR BY AT
CCS A # LEAST TWO, WE CAN PROCEED IMMEDIATELY
TCF DVNORM # WITHOUT NORMALIZATION PRODUCING A DVMAX.
-1/2+2 OCT 60001 # USED IN SQRTSUB.
TCF +1 # IF THE ABOVE DOES NOT HOLD, FORCE SIGN
CAF HALF # AGREEMENT IN NUMERATOR AND DENOMINATOR
DOUBLE # TO FACILITATE OVERFLOW AND NEAR-ONE
AD MPAC +1 # CHECKING.
TS MPAC +1
CAF ZERO
AD POSMAX
ADS MPAC
CAF HALF # SAME FOR BUF.
DOUBLE
AD BUF +1
TS BUF +1
CAF ZERO
AD POSMAX
ADS BUF
CS MPAC # CHECK MAGNITUDE OF SIGN-CORRECTED
AD BUF # OPERANDS.
CCS A
TCF DVNORM # DIVIDE OK -- WILL NOT BECOME MAXOV CASE.
LBUF2 ADRES BUF2
TCF DVOVF # DIVISOR NOT LESS THAN DIVIDEND -- OVF.
TS MAXDVSW # IF THE MAJOR PARTS OF THE DIVIDEND AND
CS MPAC +1 # DIVISOR ARE EQUAL, A SPECIAL APPROXIMA-
AD BUF +1 # TION IS USED (PROVIDED THE DIVISION IS
EXTEND # POSSIBLE, OF COURSE).
BZMF DVOVF
TCF DVNORM # IF NO OVERFLOW.
# Page 1060
BUFNORM EXTEND # ADD -1 TO AUGMENT SHIFT COUNT AND SHIFT
AUG DVNORMCT # LEFT ONE PLACE.
EXTEND
DCA BUF
DAS BUF
DVNORM CA BUF # SEE IF DIVISOR NORMALIZED YET.
DOUBLE
OVSK
TCF BUFNORM # NO -- SHIFT LEFT ONE AND TRY AGAIN.
DXCH MPAC # CALL DIVIDEND NORMALIZATION SEQUENCE
INDEX DVNORMCT # PRIOR TO DOING THE DIVIDE.
TC MAXTEST
TS MPAC +2 # RETURNS WITH DIVISION DONE AND C(A) = 0.
TCF DANZIG
BUFPOS CCS A
TCF BUF+ # TO BUF+ IF BUF IS GREATER THAN +1.
CS BUF +1 # IF BUF IS +1, FORCING SIGN AGREEMENT
EXTEND # MAY CAUSE BUF TO BECOME ZERO.
BZMF BUF+ # BRANCH IF SIGNS AGREE.
CA HALF # SIGNS DISAGREE. FORCE AGREEMENT.
+6 DOUBLE
ADS BUF +1
CA ZERO
TS BUF
TCF BUFZERO
BUFNEG CCS A
TCF BUF- # TO BUF- IF BUF IS LESS THAN -1.
CA BUF +1 # IF BUF IS -1, FORCING SIGN AGREEMENT
EXTEND # MAY CAUSE BUF TO BECOME ZERO.
BZMF BUF- # BRANCH IF SIGNS AGREE.
CS HALF # SIGNS DISAGREE. FORCE AGREEMENT.
TCF BUFPOS +6
# Page 1061
# THE FOLLOWING ARE PROLOGUES TO SHIFT THE DIVIDEND ARRIVING IN A AND L BEFORE THE DIVIDE.
-21D LXCH SR # SPECIAL PROLOGUE FOR UNIT WHEN THE
EXTEND # LENGTH OF THE ARGUMENT WAS NOT LESS THAN
MP HALF # .5. IN THIS CASE, EACH COMPONENT MUST BE
XCH L # SHIFTED RIGHT ONE TO PRODUCE A HALF-UNIT
AD SR # VECTOR.
XCH L
TCF GENDDV +1 # WITH DP DIVIDEND IN A,L.
DDOUBL # PROLOGUE WHICH NORMALIZES THE DIVIDEND
DDOUBL # WHEN IT IS KNOWN THAT NO DIVISION
DDOUBL # OVEFLOW WILL OCCUR.
DDOUBL
DDOUBL
DDOUBL
DDOUBL
DDOUBL
DDOUBL
DDOUBL
DDOUBL
DDOUBL
DDOUBL
DXCH MPAC
MAXTEST CCS MAXDVSW # 0 IF MAJORS MIGHT BE =, -1 OTHERWISE.
BIASHI DEC .4192 B-1 # SQRT CONSTANTS.
TCF MAXDV # CHECK TO SEE IF THAY ARE NOW EQUAL.
# Page 1062
# THE FOLLOWING IS A GENERAL PURPOSE DOUBLE PRECISION DIVISION ROUTINE. IT DIVIDES MPAC BY BUF AND LEAVES
# THE RESULT IN MPAC. THE FOLLOWING CONDITIONS MUST BE SATISFIED:
#
# 1. THE DIVISOR (BUF) MUST BE POSITIVE AND NOT LESS THAN .5.
#
# 2. THE DIVIDEND (MPAC) MUST BE POSITIVE WITH THE MAJOR PART OF MPAC STRICTLY LESS THAN THAT OF BUF
# (A SPECIAL APPROXIMATION, MAXDV, IS USED WHEN THE MAJOR PARTS ARE EQUAL).
#
# UNDERSTANDING THAT A/B = Q + S(R/B) WHERE S = 2(-14) AND Q AND R ARE QUOTIENT AND REMAINDER, RESPEC-
# TIVELY, THE FOLLOWING APPROXIMATION IS OBTAINED BY MULTIPLYING ABOVE AND BELOW BY C - SD AND NEGLECTING TERMS OF
# ORDER S-SQUARED (POSSIBLY INTRODUCING ERROR INTO THE LOW TWO BITS OF THE RESULT). SIGN AGREEMENT IS UNNECESSARY.
#
# A + SB . (R - QD) A + SB
# ------ = Q + S(------) WHERE Q AND R ARE QUOTIENT AND REMAINDER OF ------ RESPECTIVELY.
# C + SD ( C } C
GENDDV DXCH MPAC # WE NEED A AND B ONLY FOR FIRST DV.
+1 EXTEND # (SPECIAL UNIT PROLOGUE ENTERS HERE).
DV BUF # A NOW CONTAINS Q AND L, R.
DXCH MPAC
CS MPAC # FORM DIVIDEND FOR MINOR PART OF RESULT.
EXTEND
MP BUF +1
AD MPAC +1 # OVERFLOW AT THIS POINT IS POSITIVE SINCE
OVSK # R IS POSITIVE IN EVERY CASE.
TCF +5
EXTEND # OVERFLOW CAN BE REMOVED BY SUBTRACTING C
SU BUF # (BUF) ONCE SINCE R IS ALWAYS LESS THAN C
INCR MPAC # IN THIS CASE. INCR COMPENSATES SUBTRACT.
TCF +DOWN # (SINCE C(A) IS STILL POSITIVE).
+5 EXTEND # C(A) CAN BE MADE LESS THAN C IN MAGNI-
BZMF -UP # TUDE BY DIMINISHING IT BY C (SINCE C IS
# NOT LESS THAN .5) UNLESS C(A) = 0.
# Page 1063
+DOWN EXTEND
SU BUF # IF POSITIVE, REDUCE ONLY IF NECESSARY
EXTEND # SINCE THE COMPENSATING INCR MIGHT CAUSE
BZF +3 # OVERFLOW.
EXTEND # DON'T SUBTRACT UNLESS RESULT IS POSITIVE
BZMF ENDMAXDV # OR ZERO.
+3 INCR MPAC # KEEP SUBTRACT HERE AND COMPENSATE.
TCF FINALDV
-UP EXTEND # IF ZERO, SET MINOR PART OF RESULT TO
BZF FINALDV +3 # ZERO.
EXTEND # IF NEGATIVE, ADD C TO A, SUBTRACTING ONE
DIM MPAC # TO COMPENSATE. DIM IS OK HERE SINCE THE
ENDMAXDV AD BUF # MAJOR PART NEVER GOES NEGATIVE.
# Page 1064
FINALDV ZL # DO DV TO OBTAIN MINOR PART OF RESULT.
EXTEND
DV BUF
+3 TS MPAC +1
CCS DVSIGN # LEAVE RESULT POSITIVE UNLESS C(DVSIGN)=
TC Q # -0.
TC Q
TC Q
EXTEND
DCS MPAC
DXCH MPAC
CAF ZERO # SO WE ALWAYS RETURN WITH C(A) = 0.
TC Q
# Page 1065
# IF THE MAJOR PARTS OF THE DIVISOR AND DIVIDEND ARE EQUAL, BUT THE MINOR PARTS ARE SUCH THAT THE
# DIVIDEND IS STRICTLY LESS THAN THE DIVISOR IN MAGNITUDE, THE FOLLOWING APPROXIMATION IS USED. THE ASSUMPTIONS
# ARE THE SAME AS THE GENERAL ROUTINE WITH THE ADDITION THAT SIGN AGREEMENT IS NECESSARY (B, C, & D POSITIVE).
#
# C + SB . (C + B - D)
# ------ = 37777 + S(---------)
# C + SD ( C )
#
# THE DIVISION MAY BE PERFORMED IMMEDIATELY SINCE B IS STRICTLY LESS THAN D AND C IS NOT LESS THAN .5.
MAXDV CS MPAC # SEE IF MAXDV CASE STILL HOLDS AFTER
AD BUF # NORMALIZATION.
EXTEND
BZF +2
TCF GENDDV # MPAC NOW LESS THAN BUFF -- DIVIDE AS USUAL.
+2 CAF POSMAX # SET MAJOR PART OF RESULT.
TS MPAC
CS BUF +1 # FORM DIVIDEND OF MINOR PART OF RESULT.
AD MPAC +1
TCF ENDMAXDV # GO ADD C AND DO DIVIDE, ATTACHING SIGN
# BEFORE EXITING.
# Page 1066
# VECTOR DIVIDED BY SCALAR, V/SC, IS EXECUTED HERE. THE VECTOR IS NOW IN MPAC WITH SCALAR IN BUF.
V/SC2 CS ONE # INITIALIZE DIVIDEND NORMALIZATION COUNT
TS DVNORMCT # AND DIVISION SIGN REGISTER.
TS VBUF +5
TC VECAGREE # FORCE SIGN AGREEMENT IN VECTOR
DXCH BUF
TC ALSIGNAG # SIGN AGREE BUF
DXCH BUF
CCS BUF # FORCE DIVISOR POSITIVE WITH MAJOR PART
TCF /BUF+ # NON-ZERO (IF POSSIBLE).
TCF +2
TCF /BUF-
XCH BUF +1 # SHIFT VECTOR AND SCALAR LEFT 14.
XCH BUF
XCH MPAC +1
XCH MPAC
EXTEND # CHECK FOR OVERFLOW IN EACH CASE.
BZF +2
TCF DVOVF
XCH MPAC +4
XCH MPAC +3
EXTEND
BZF +2
TCF DVOVF
XCH MPAC +6
XCH MPAC +5
EXTEND
BZF +2
TCF DVOVF
CCS BUF
TCF /BUF+
TCF DVOVF # ZERO DIVISOR - OVERFLOW.
TCF /BUF-
TCF DVOVF
/BUF- EXTEND # ON NEGATIVE, COMPLEMENT BUF AND MAINTAIN
DCS BUF # DVSIGN IN VBUF +5.
DXCH BUF
INCR VBUF +5
# Page 1067
/BUF+ EXTEND
DCA BUF # LEAVE ABS(ORIG DIVISOR) IN BUF2
DXCH BUF2 # FOR OVERFLOW TESTING
TCF /NORM # NORMALIZE DIVISOR IN BUF.
/NORM2 EXTEND # IF LESS THAN .5, AUGMENT DVNORMCT AND
AUG DVNORMCT # DOUBLE DIVISOR.
EXTEND
DCA BUF
DAS BUF
/NORM CA BUF # SEE IF DIVISOR NORMALIZED.
DOUBLE
OVSK
TCF /NORM2 # DOUBLE AND TRY AGAIN IF NOT.
TC V/SCDV # DO X COMPONENT DIVIDE.
DXCH MPAC +3 # SUPPLY ARGUMENTS IN USUAL SEQUENCE.
DXCH MPAC
DXCH MPAC +3
TC V/SCDV # Y COMPONENT.
DXCH MPAC +5
DXCH MPAC
DXCH MPAC +5
TC V/SCDV # Z COMPONENT.
TCF VROTATEX # GO RE-ARRANGE COMPONENTS BEFORE EXIT.
# Page 1068
# SUBROUTINE USED BY V/SC TO DIVIDE VECTOR COMPONENT IN MPAC,+1 BY THE SCALAR GIVEN IN BUF.
V/SCDV CA VBUF +5 # REFLECTS SIGN OF SCALAR.
TS DVSIGN
CCS MPAC # FORCE MPAC POSITIVE, EXITING ON ZERO.
TCF /MPAC+
TCF +2
TCF /MPAC-
CCS MPAC +1
TCF /MPAC+
TC Q
TCF /MPAC-
TC Q
/MPAC- EXTEND # USUAL COMPLEMENTING AND SETTING OF SIGN.
DCS MPAC
DXCH MPAC
INCR DVSIGN
/MPAC+ CS ONE # INITIALIZE NEAR-ONE SWITCH.
TS MAXDVSW
CS MPAC # CHECK POSSIBLE OVERFLOW.
AD BUF2 # UNNORMALIZED INPUT DIVISOR.
CCS A
TCF DDVCALL # NOT NEAR-ONE
TCF +2 # +0 IS JUST POSSIBLE
TCF DVOVF # NO HOPE
TS MAXDVSW # SIGNAL POSSIBLE NEAR-ONE CASE
CS MPAC +1 # SEE IF DIVISION CAN BE DONE
AD BUF2 +1
EXTEND
BZMF DVOVF
DDVCALL DXCH MPAC # CALL PRE-DIVIDE NORMALIZATION.
INDEX DVNORMCT
TCF MAXTEST
# Page 1069
SLOPELO DEC .8324
VECAGREE XCH Q # SAVE Q IN A
DXCH MPAC
TC ALSIGNAG # SIGNAGREE MPAC
DXCH MPAC
DXCH MPAC +3
TC ALSIGNAG # SIGN AGREE MPAC +3
DXCH MPAC +3
DXCH MPAC +5
TC ALSIGNAG # SIGNAGREE MPAC +5
DXCH MPAC +5
TC A
# Page 1070
# THE FOLLOWING ROUTINE EXECUTES THE UNIT INSTRUCTION, WHICH TAKES THE UNIT OF THE VECTOR IN MPAC.
UNIT TC VECAGREE # FORCE SIGN AGREEMENT IN VECTOR
TC MPACVBUF # SAVE ARGUMENT IN VBUF
CAF ZERO # MUST SENSE OVERFLOW IN FOLLOWING DOT.
XCH OVFIND
TS TEM1
TC VSQSUB # DOT MPAC WITH ITSELF.
CA TEM1
XCH OVFIND
EXTEND
BZF +2
TCF DVOVF
EXTEND
DCA MPAC # LEAVE THE SQUARE OF THE LENGTH OF THE
INDEX FIXLOC # ARGUMENT IN LVSQUARE.
DXCH LVSQUARE
TC SQRTSUB # GO TAKE THE NORMALIZED SQUARE ROOT.
CCS MPAC # CHECK FOR UNIT OVERFLOW.
TCF +5 # MPAC IS NOT LESS THAN .5 UNLESS
TS L
INDEX FIXLOC
DXCH LV
TCF DVOVF # INPUT TO SQRTSUB WAS 0.
CS FOURTEEN # SEE IF THE INPUT WAS SO SMALL THAT THE
AD MPTEMP # FIRST TWO REGISTERS OF THE SQUARE WERE 0
CCS A
COM # IF SO, SAVE THE NEGATIVE OF THE SHIFT
TCF SMALL # COUNT -15D.
TCF LARGE # (THIS IS USUALLY THE CASE.)
CS THIRTEEN # IF THE SHIFT COUNT WAS EXACTLY 14, SET
TS MPTEMP # THE PRE-DIVIDE NORM COUNT TO -13D.
CA MPAC # SHIFT THE LENGTH RIGHT 14 BEFORE STORING
SMALL2 TS L # (SMALL EXITS TO THIS POINT).
CAF ZERO
TCF LARGE2 # GO TO STORE LENGTH AND PROCEED.
LARGE CCS MPTEMP # MOST ALL CASES COME HERE.
TCF LARGE3 # SEE IF NO NORMALIZATION WAS REQUIRED BY
CS SRDDV # SQRT, AND IF SO, SET UP FOR A SHIFT
TS MPTEMP # RIGHT 1 BEFORE DIVIDING TO PRODUCE
EXTEND # THE DESIRED HALF UNIT VECTOR.
DCA MPAC
# Page 1071
TCF LARGE2
# Page 1072
LARGE3 COM # LEAVE NEGATIVE OF SHIFT COUNT-1 FOR
TS MPTEMP # PREDIVIDE LEFT SHIFT.
COM # PICK UP REQUIRED SHIFTING BIT TO UNNORM-
INDEX A # ALIZE THE SQRT RESULT.
CAF BIT14
TS BUF
EXTEND
MP MPAC +1
XCH BUF
EXTEND # (UNNORMALIZE THE SQRT FOR LV).
MP MPAC
XCH L
AD BUF
XCH L
LARGE2 INDEX FIXLOC
DXCH LV # LENGTH NOW STORED IN WORK AREA.
CS ONE
TS MAXDVSW # NO MAXDV CASES IN UNIT.
DXCH VBUF # PREPARE X COMPONENT FOR DIVIDE, SETTING
DXCH MPAC # LENGTH OF VECTOR AS DIVISOR IN BUF.
DXCH BUF
TC UNITDV
DXCH VBUF +2 # DO Y AND Z IN USUAL FASHION SO WE CAN
DXCH MPAC # EXIT THROUGH VROTATEX.
DXCH MPAC +3
TC UNITDV
DXCH VBUF +4
DXCH MPAC
DXCH MPAC +5
TC UNITDV
TCF VROTATEX # AND EXIT.
# Page 1073
# IF THE LENGTH OF THE ARGUMENT VECTOR WAS LESS THAN 2(-28), EACH COMPONENT MUST BE SHIFTED LEFT AT LEAST
# 14 PLACES BEFORE THE DIVIDE. NOTE THAT IN THIS CASE, THE MAJOR PART OF EACH COMPONENT IS ZERO.
SMALL TS MPTEMP # NEGATIVE OF PRE-DIVIDE SHIFT COUNT.
CAF ZERO # SHIFT EACH COMPONENT LEFT 14.
XCH VBUF +1
XCH VBUF
XCH VBUF +3
XCH VBUF +2
XCH VBUF +5
XCH VBUF +4
CS MPTEMP
INDEX A
CAF BIT14
EXTEND
MP MPAC
TCF SMALL2
THIRTEEN = OCT15
FOURTEEN = OCT16
OCT16 = R1D1
# Page 1074
# THE FOLLOWING ROUTINE SETS UP THE CALL TO THE DIVIDE ROUTINES.
UNITDV CCS MPAC # FORCE MPAC POSITIVE IF POSSIBLE, SETTING
TCF UMPAC+ # DVSIGN ACCORDING TO THE SIGN OF MPAC
TCF +2 # SINCE THE DIVISOR IS ALWAYS POSITIVE
TCF UMPAC- # HERE.
CCS MPAC +1
TCF UMPAC+
TC Q # EXIT IMMEDIATELY ON ZERO.
TCF UMPAC-
TC Q
UMPAC- CS ZERO # IF NEGATIVE, SET -0 IN DVSIGN FOR FINAL
TS DVSIGN # COMPLEMENT.
EXTEND
DCS MPAC # PICK UP ABSOLUTE VALUE OF ARG AND JUMP.
INDEX MPTEMP
TCF MAXTEST -1
UMPAC+ TS DVSIGN # SET DVSIGN FOR POSITIVE QUOTIENT.
DXCH MPAC
INDEX MPTEMP
TCF MAXTEST -1
# Page 1075
# MISCELLANEOUS UNARY OPERATIONS.
DSQ TC DSQSUB # SQUARE THE DP CONTENTS OF MPAC.
TCF DANZIG
ABVALABS CCS MODE # ABVAL OR ABS INSTRUCTION.
TCF ABS # DO ABS ON SCALAR.
TCF ABS
ABVAL TC VSQSUB # DOT MPAC WITH ITSELF.
LXCH MODE # MODE IS NOW DP (L ZERO AFTER DAS).
EXTEND # STORE SQUARE OF LENGTH IN WORK AREA.
DCA MPAC
INDEX FIXLOC
DXCH LVSQUARE
# Page 1076
# PROGRAM DESCRIPTION -- SUBROUTINE SQRT
#
# FUNCTIONAL DESCRIPTION -- DOUBLE PRECISION SQUARE ROOT ROUTINE
# THIS PROGRAM TAKES THE SQUARE ROOT OF THE 27 OR 28 MOST SIGNIFICANT BITS IN THE TRIPLE PRECISION SET OF
# NUMBERS -- MPAC, MPAC+1, AND MPAC+2. THE ROOT IS RETURNED DOUBLE PRECISION IN MPAC AND MPAC+1.
#
# WARNING -- THIS SUBROUTINE USES A TRIPLE PRECISION INPUT. THE PROGRAMMER MUST ASSURE THE CONTENTS OF MPAC+2
# ESPECIALLY IF THE CONTENTS OF MPAC IS SMALL OR ZERO. FOR DETAILS SEE STG MEMO NO.949.
#
# CALLING SEQUENCE -- IN INTERPRETIVE MODE, I.E., FOLLOWING `TC INTPRET', `SQRT', NO ADDRESS IS ALLOWED.
# INPUT SCALING: THE BINARY POINT IS ASSUMED TO THE RIGHT OF BIT 15. THE ANSWER IS RETURNED WITH THE SAME SCALING.
#
# SUBROUTINES -- GENSCR, MPACSHR, SQRTSUB, ABORT
#
# ABORT EXIT MODE -- ABORTS ON NEGATIVE INPUT -1.2X10E-4 (77775 OCTAL) OR LESS.
# DISPLAYS ERROR CODE 1302
# TC ABORT
# OCT 1302
#
# DEBRIS -- LOCATIONS BUF, MPTEMP, ADDRWD ARE USED
SQRT TC SQRTSUB # TAKE THE SQUARE ROOT OF MPAC.
CCS MPTEMP # RETURNED NORMALIZED SQUARE ROOT. SEE IF
TCF +2 # ANY UN-NORMALIZATION REQUIRED AND EXIT
TCF DANZIG # IF NOT.
AD NEG12 # A RIGHT SHIFT OF MORE THAN 13 COULD BE
EXTEND # REQUIRED IF INPUT WAS ZERO IN MPAC,+1.
BZMF SQRTSHFT # GOES HERE IN MOST CASES.
ZL # IF A LONG SHIFT IS REQUIRED, GO TO
LXCH ADDRWD # GENERAL RIGHT SHIFT ROUTINES.
TCF GENSCR +4 # ADDRWD WAS ZERO TO PREVENT ROUND.
SQRTSHFT INDEX MPTEMP # SELECT SHIFTING BIT AND EXIT THROUGH
CAF BIT15 # SHIFT ROUTINES.
TS MPTEMP
CAF ZERO # TO ZERO MPAC +2 IN THE PROCESS.
TCF MPACSHR +3
ABS TC BRANCH # TEST SIGN OF MPAC AND COMPLEMENT IF
TCF DANZIG
TCF DANZIG
TCF COMP
# Page 1077
VDEF CS FOUR # VECTOR DEFINE -- ESSENTIALLY TREATS
ADS PUSHLOC # SCALAR IN MPAC AS X COMPONENT, PUSHES UP
EXTEND # FOR Y AND THEN AGAIN FOR Z.
INDEX A
DCA 2
DXCH MPAC +3
EXTEND
INDEX PUSHLOC
DCA 0
DXCH MPAC +5
TCF VMODE # MODE IS NON VECTOR.
VSQ TC VSQSUB # DOT MPAC WITH ITSELF.
TCF DMODE # MODE IS NOW DP.
PUSH EXTEND # PUSH DOWN MPAC LEAVING IT LOADED.
DCA MPAC
INDEX PUSHLOC # PUSH DOWN FIRST TWO REGISTERS IN EACH
DXCH 0
INDEX MODE # INCREMENT PUSHDOWN POINTER.
CAF NO.WDS
ADS PUSHLOC
CCS MODE
TCF TPUSH # PUSH DOWN MPAC +2.
TCF DANZIG # DONE FOR DP.
EXTEND # ON VECTOR, PUSH DOWN Y AND Z COMPONENTS.
DCA MPAC +3
INDEX PUSHLOC
DXCH 0 -4
EXTEND
DCA MPAC +5
INDEX PUSHLOC
DXCH 0 -2
TCF DANZIG
TPUSH CA MPAC +2
TCF ENDTPUSH +2
RVQ INDEX FIXLOC # RVQ -- RETURN IVA QPRET.
CA QPRET
TS POLISH
TCF GOTO +4 # (ASSUME QPRET POINTS TO FIXED ONLY.)
# Page 1078
# THE FOLLOWING SUBROUTINES ARE USED IN SQUARING MPAC, IN BOTH THE SCALAR AND VECTOR SENSE. THEY ARE
# SPECIAL CASES OF DMPSUB AND DOTSUB, PUT IN TO SAVE SOME TIME.
DSQSUB CA MPAC +1 # SQUARES THE SCALAR CONTENTS OF MPAC.
EXTEND
SQUARE
TS MPAC +2
CAF ZERO # FORM 2(CROSS TERM).
XCH MPAC +1
EXTEND
MP MPAC
DDOUBL # AND MAYBE OVEFLOW.
DAS MPAC +1 # AND SET A TO NET OVERFLOW.
XCH MPAC
EXTEND
SQUARE
DAS MPAC
TC Q
VSQSUB EXTEND # DOTS THE VECTOR IN MPAC WITH ITSELF.
QXCH DOTRET
TC DSQSUB # SQUARE THE X COMPONENT.
DXCH MPAC +3
DXCH MPAC
DXCH BUF # SO WE CAN END IN DOTSUB.
CA MPAC +2
TS BUF +2
TC DSQSUB # SQUARE Y COMPONENT.
DXCH MPAC +1
DAS BUF +1
AD MPAC
AD BUF
TS BUF
TCF +2
TS OVFIND # IF OVERFLOW.
DXCH MPAC +5
DXCH MPAC
TC DSQSUB # SQUARE Z COMPONENT.
TCF ENDDOT # END AS IN DOTSUB.
# Page 1079
# DOUBLE PRECISION SQUARE ROOT ROUTINE. TAKE THE SQUARE ROOT OF THE TRIPLE PRECISION (MPAC +2 USED ONLY
# IN NORMALIZATION) CONTENTS OF MPAC AND LEAVE THE NORMALIZED RESULT IN MPAC (C(MPAC) GREATER THAN OR EQUAL TO
# .5). THE RIGHT SHIFT COUNT (TC UNNORMALIZE) IS LEFT IN MPTEMP.
SQRTSUB CAF ZERO # START BY ZEROING RIGHT SHIFT COUNT.
TS MPTEMP
CCS MPAC # CHECK FOR POSITIVE ARGUMENT, SHIFTING
TCF SMPAC+ # FIRST SIGNIFICANT MPAC REGISTER INTO
TCF +2 # MPAC ITSELF.
TCF SQRTNEG # SEE IF MAG OF ARGUMENT LESS THAN 10(-4).
XCH MPAC +2 # MPAC IS ZERO -- SHIFT LEFT 14.
XCH MPAC +1
TS MPAC
CAF SEVEN # AUGMENT RIGHT SHIFT COUNTER.
TS MPTEMP
CCS MPAC # SEE IF MPAC NOW PNZ.
TCF SMPAC+
TCF +2
TCF ZEROANS # NEGATIVE BUT LESS THAN 10(-4) IN MAG.
XCH MPAC +1 # XERO -- SHIFT LEFT 14 AGAIN.
TS MPAC
CAF SEVEN # AUGMENT RIGHT SHIFT COUNTER.
ADS MPTEMP
CCS MPAC
TCF SMPAC+
TC Q # SQRT(0) = 0.
TCF ZEROANS
TCF FIXROOT # DO NOT LEAVE SQRTSUB WITH -0 IN MPAC.
SQRTNEG CCS A # ARGUMENT IS NEGATIVE, BUT SEE IF SIGN-
TCF SQRTABRT # CORRECTED ARGUMENT IS LESS THAN 10(-4)
CCS MPAC +1 # IN MAGNITUDE. IF SO, CALL ANSWER ZERO.
ZEROANS CAF ZERO # FORCE ANSWER TO ZERO HERE.
TCF FIXROOT
TCF SQRTABRT
TCF FIXROOT
SQRTABRT DXCH LOC
TC POODOO1
OCT 1302
# Page 1080
SMPAC+ AD -1/2+2 # SEE IF ARGUMENT GREATER THAN OR EQUAL TO
EXTEND # .5.
BZMF SRTEST # IF SO, SEE IF LESS THAN .25.
DXCH MPAC # WE WILL TAKE THE SQUARE ROOT OF MPAC/2.
LXCH SR # SHIFT RIGHT 1 AND GO TO THE SQRT ROUTINE
EXTEND
MP HALF
DXCH MPAC
XCH SR
ADS MPAC +1 # GUARANTEED NO OVERFLOW.
ARGHI CAF SLOPEHI # ARGUMENT BETWEEN .25 AND .5, GET A
EXTEND # LINEAR APPROXIMATION FOR THIS RANGE.
MP MPAC
AD BIASHI # X0/2 = (MPAC/2)(SLOPHI) + BIASHI/2.
+4 TS BUF # X0/2 (ARGLO ENTERS HERE).
CA MPAC # SINGLE-PRECISION THROUGHOUT.
ZL
EXTEND
DV BUF # (MPAC/2)/(X0/2)
EXTEND
MP HALF
ADS BUF # X1 = X0/2 + .5(MPAX/2)/(X0/2)
EXTEND
MP HALF # FORM UP X1/2.
DXCH MPAC # SAVE AND BRING OUT ARGUMENT.
EXTEND # TAKE DP QUOTIENT WITH X1.
DV BUF
TS BUF +1 # SAVE MAJOR PART OF QUOTIENT.
CAF ZERO # FORM MINOR PART OF QUOTIENT USING
XCH L # (REMAINDER,0).
EXTEND
DV BUF
TS L # IN PREPARATION FOR DAS.
CA BUF +1
DAS MPAC # X2 = X1/2 + (MPAC/2)X1
EXTEND # OVERFLOWS IF ARG. NEAR POSMAX.
BZF TCQBNK00
CAF POSMAX
FIXROOT TS MPAC
TS MPAC +1
TCQBNK00 TC Q # RETURN TO CALLER TO UNNORMALIZE, ETC.
# Page 1081
SRTEST AD QUARTER # ARGUMENT WAS LESS THAN .5, SEE IF LESS
EXTEND # THAN .25.
BZMF SQRTNORM # IF SO, BEGIN NORMALIZATION.
DXCH MPAC # IF BETWEEN .5 AND .25, SHIFT RIGHT 1 AND
LXCH SR # START AT ARGLO.
EXTEND
MP HALF
DXCH MPAC
XCH SR
ADS MPAC +1 # NO OVERFLOW.
ARGLO CAF SLOPELO # (NORMALIZED) ARGUMENT BETWEEN .125 AND
EXTEND # .25
MP MPAC
AD BIASLO
TCF ARGHI +4 # BEGIN SQUARE ROOT.
SQRTNM2 EXTEND # SHIFT LEFT 2 AND INCREMENT RIGHT SHIFT
DCA MPAC +1 # COUNT (FOR TERMINAL UNNORMALIZATION).
DAS MPAC +1
AD MPAC
ADS MPAC # (NO OVERFLOW).
SQRTNORM INCR MPTEMP # FIRST TIME THROUGH, JUST SHIFT LEFT 1
EXTEND # (PUTS IN EFFECTIVE RIGHT SHIFT SINCE
DCA MPAC +1 # WE WANT MPAC/2).
DAS MPAC +1
AD MPAC
ADS MPAC # (AGAIN NO OVERFLOW).
DOUBLE
TS CYL
NORMTEST CCS CYL # SEE IF ARGUMENT NOW NORMALIZED AT
CCS CYL # GREATER THAN .125.
TCF SQRTNM2 # NO -- SHIFT LEFT 2 MORE AND TRY AGAIN.
TCF ARGHI # YES -- NOW BETWEEN .5 AND .25.
TCF ARGLO # ARGUMENT NOW BETWEEN .25 AND .125.
# Page 1082
# TRIGONOMETRIC FUNCTION PACKAGE.
# THE FOLLOWING TRIGONOMETRIC FUNCTIONS ARE AVAIALABLE AS INTERPRETIVE OPERATIONS:
# 1. SIN COMPUTES (1/2)SINE(2 PI MPAC).
# 2. COS COMPUTES (1/2)COSINE(2 PI MPAC).
# 3. ASIN COMPUTES (1/2PI)ARCSINE(2 MPAC).
# 4. ACOS COMPUTES (1/2PI)ARCCOSINE(2 MPAC).
#
# SIN-ASIN AND COS-ACOS ARE MUTUALLY INVERSE, I.E., SIN(ASIN(X)) = X.
COSINE TC BRANCH # FINDS COSINE USING THE IDENTITY
TCF +3 # COS(X) = SIN(PI/2 - ABS(X)).
TCF PRESINE
TCF PRESINE
+3 EXTEND
DCS MPAC
DXCH MPAC
PRESINE CAF QUARTER # PI/2 SCALED.
ADS MPAC
SINE DXCH MPAC # DOUBLE ARGUMENT.
DDOUBL
OVSK # SEE IF OVERFLOW PRESENT.
TCF +3 # IF NOT, ARGUMENT OK AS IS.
EXTEND # IF SO, WE LOST (OR GAINED) PI, SO
DCOM # COMPLEMENT MPAC USING THE IDENTITY
# SIN(X-(+)PI) = SIN(-X).
+3 DXCH MPAC
CA MPAC # SEE IF ARGUMENT GREATER THAN .5 IN
DOUBLE # MAGNITUDE. IF SO, REDUCE IT TO LESS THAN
TS L # .5 (+-PI/2 SCALED) AS FOLLOWS:
TCF SN1
INDEX A # IF POSITIVE, FORM PI - X, IF NEGATIVE
CAF NEG1/2 +1 # USE -PI -X.
DOUBLE
EXTEND
SU MPAC # GUARANTEED NO OVERFLOW.
TS MPAC
CS MPAC +1
TS MPAC +1
# Page 1083
SN1 EXTEND # SET UP TO EVALUATE HASTINGS POLYNOMIAL
DCA MPAC
DXCH BUF2
TC DSQSUB # SQUARE MPAC.
TC POLY # EVALUATE FOURTH ORDER POLYNOMIAL.
DEC 3
2DEC +.3926990796
2DEC -.6459637111
2DEC +.318758717
2DEC -.074780249
2DEC +.009694988
CAF LBUF2 # MULTIPLY BY ARGUMENT AND SHIFT LEFT 2.
TC DMPSUB -1
EXTEND
DCA MPAC +1
DAS MPAC +1
AD MPAC
ADS MPAC # NEITHER SHIFT OVERFLOWS.
EXTEND
DCA MPAC +1
DAS MPAC +1
AD MPAC
ADS MPAC
TCF DANZIG
# Page 1084
# ARCSIN/ARCCOS ROUTINE.
ARCSIN CAF LASINEX # COMPUTE ARCSIN BY USING THE IDENTITY
TCF +2 # ARCSIN(X) = PI/2 - ARCCOS(X).
ARCCOS CAF LDANZIG # (EXITS IMMEDIATELY).
TS ESCAPE
TC BRANCH # TEST SIGN OF INPUT.
TCF ACOSST # START IMMEDIATELY IF POSITIVE.
TCF ACOSZERO # ARCCOS(0) = PI/2 = .25.
EXTEND # IF NEGATIVE, USE THE IDENTITY
DCS MPAC # ARCCOS(X) = PI - ARCCOS(-X), FORCING
DXCH MPAC # ARGUMENT POSITIVE.
CAF TCSUBTR # SET EXIT TO DO ABOVE BEFORE
XCH ESCAPE # ARCSIN/ARCCOS CONSIDERATIONS.
TS ESCAPE2
ACOSST CS HALF # TEST MAGNITUDE OF INPUT.
AD MPAC
CCS A
TCF ACOSOVF # THIS IS PROBABLY AN OVERFLOW CASE.
LASINEX TCF ASINEX
TCF ACOSST2 # NO OVERFLOW -- PROCEED.
CCS MPAC +1 # IF MAJOR PART IS .5, CALL ANSWER 0
CAF ZERO # UNLESS MINOR PART NEGATIVE.
TCF ACOS=0
TCF ACOSST2
ACOS=0 TS MPAC +1
TS MPAC
TC ESCAPE
ACOSST2 EXTEND # NOW THAT ARGUMENT IS IN PROPER RANGE,
DCS MPAC # BEGIN COMPUTATION. USE HASTINGS
AD HALF # APPROXIMATION ARCCOS(X) = SQRT(1-X)P(X)
DXCH MPAC # IN A SCALED VERSION WHERE P(X) IS A
DXCH BUF2 # SEVENTH ORDER POLYNOMIAL.
TC SQRTSUB # RETURNS WITH NORMALIZED SQUARE ROOT.
CCS MPTEMP # SEE IF UN-NORMALIZATION REQUIRED.
TCF ACOSSHR # IF SO.
# Page 1085
ACOS3 DXCH MPAC # SET UP FOR POLYNOMIAL EVALUATION.
DXCH BUF2
DXCH MPAC
TC POLY
DEC 6
2DEC +.353553385 # COEFFICIENTS ARE C 2(+I)/PISQRT(2) WHERE
2DEC* -.0483017006 B+1* # I
2DEC* +.0200273085 B+2* # WHERE C STANDS FOR ORIGINAL COEFFS.
2DEC* -.0112931863 B+3*
2DEC* +.00695311612 B+4*
2DEC* -.00384617957 B+5*
2DEC* +.001501297736 B+6*
2DEC* -.000284160334 B+7*
CAF LBUF2 # DO FINAL MULTIPLY AND GO TO ANY
TC DMPSUB -1 # EPILOGUE SEQUENCES.
TC ESCAPE
SUBTR EXTEND # EPILOGUE FOR NEGATIVE INPUTS TO ARCCOS.
DCS MPAC
AD HALF # FORMS PI - ARCCOS(-X) = ARCCOS(X).
DXCH MPAC
TC ESCAPE2 # GO TO POSSIBLE ARCSIN EPILOGUE.
ASINEX EXTEND
DCS MPAC # ARCSIN EPILOGUE -- GET ARCSIN(X)
AD QUARTER # = PI/2 - ARCCOS(X).
DXCH MPAC
LDANZIG TCF DANZIG
# Page 1086
ACOSSHR INDEX A # THE SHIFT RIGHT IS LESS THAN 14 SINCE
CAF BIT14 # THE INPUT WAS NON-ZERO DP.
TS MPTEMP
TC VSHRRND # DP SHIFT RIGHT AND ROUND.
TCF ACOS3 # PROCEED.
ACOSOVF EXTEND # IF MAJOR PART WAS ONLY 1 MORE THAN .5,
BZF ACOS=0 # CALL ANSWER ZERO.
ACOSABRT EXTEND # IF OVERFLOW, CALL ANSWER ZERO BUT
DCA LOC # SOUND AN ALARM.
TC ALARM1
OCT 1301
CAF ZERO
TCF ACOS=0
ACOSZERO CAF QUARTER # ACOS(0) = PI/2.
TCF ACOS=0 +1 # SET MPAC AND EXIT VIA ESCAPE.
NEG12 DEC -12
TCSUBTR TCF SUBTR
# Page 1087
# THE FOLLOWING INSTRUCTIONS ARE AVAILABLE FOR SETTING, MODIFYING, AND BRANCHING ON INDEX REGISTERS:
# 1. AXT ADDRESS TO INDEX TRUE.
# 2. AXC ADDRESS TO INDEX COMPLEMENTED.
# 3. LXA LOAD INDEX FROM ERASABLE.
# 4. LXC LOAD INDEX COMPLEMENTED FROM ERASABLE.
# 5. SXA STORE INDEX IN ERASABLE.
# 6. XCHX EXCHANGE INDEX REGISTER WITH ERASABLE.
# 7. INCR INCREMENT INDEX REGISTER.
# 8. XAD ERASABLE ADD TO INDEX REGISTER.
# 9. XSU ERASABLE SUBTRACT FROM INDEX REGISTER.
# 10. TIX BRANCH ON INDEX REGISTER AND DECREMENT.
BANK 01
COUNT* $$/INTER
AXT TC TAGSUB # SELECT APPROPRIATE INDEX REGISTER.
CA POLISH
XSTORE INDEX INDEXLOC # CONTAINS C(FIXLOC) OR C(FIXLOC)+1
TS X1
TCF DANZIG
AXC TC TAGSUB
CS POLISH
TC XSTORE
LXA TC 15ADRERS # LOAD INDEX REGISTER FROM ERASABLE.
INDEX POLISH
CA 0
TCF XSTORE
LXC TC 15ADRERS # LOAD NDX REG FROM ERASABLE COMPLEMENTED.
INDEX POLISH
CS 0
TCF XSTORE
SXA TC 15ADRERS # STORE INDEX REGISTER IN ERASABLE.
INDEX INDEXLOC
CA X1
MSTORE1 INDEX POLISH
TS 0
TCF DANZIG
# Page 1088
XCHX TC 15ADRERS # EXCHANGE INDEX REGISTER WITH ERASABLE.
INDEX POLISH
CA 0
INDEX INDEXLOC
XCH X1
TCF MSTORE1
XAD TC 15ADRERS # ADD ERASABLE TO INDEX REGISTER.
INDEX POLISH
CA 0
XAD2 INDEX INDEXLOC
ADS X1 # IGNORING OVERFLOWS.
TCF DANZIG
INCR TC TAGSUB # INCREMENT INDEX REGISTER.
CA POLISH
TCF XAD2
XSU TC 15ADRERS # SUBTRACT ERASABLE FROM INDEX REGISTER.
INDEX POLISH
CS 0
TCF XAD2
TIX TC TAGSUB # BRANCH AND DECREMENT ON INDEX.
INDEX INDEXLOC
CS S1
INDEX INDEXLOC
AD X1
EXTEND # NO OPERATION IF DECREMENTED INDEX IS
BZMF DANZIG # NEGATIVE OR ZERO.
DOTIXBR INDEX INDEXLOC
XCH X1 # IGNORING OVERFLOWS.
TCF GOTO # DO THE BRANCH USING THE CADR IN POLISH.
# Page 1089
# SUBROUTINE TO CONVERT AN ERASABLE ADDRESS (11 BITS) TO AN EBANK SETTING AND SUBADDRESS.
15ADRERS CS POLISH
AD DEC45
CCS A # DOES THE ADDRESS POINT TO THE WORK AREA?
CA FIXLOC # YES. ADD FIXLOC. EBANK OK AS IS.
TCF +5
CA OCT1400 # NO. SET EBANK & MAKE UP SUBADDRESS.
XCH POLISH
TS EBANK
MASK LOW8
+5 ADS POLISH # FALL INTO TAGSUB, AND RETURN VIA Q.
# SUBROUTINE WHICH SETS THE ADDRESS OF THE SPECIFIED INDEX IN INDEXLOC. (ACTUALLY, THE ADDRESS -38D.)
TAGSUB CA FIXLOC
TS INDEXLOC
CCS CYR # BIT 15 SPECIFIES INDEX.
INCR INDEXLOC # 0 MEANS USE X2.
TC Q
TC Q # 1 FOR X1.
# Page 1090
# MISCELLANEOUS OPERATION CODES WITH DIRECT ADDRESSES. INCLUDED HERE ARE:
# 1. ITA STORE CPRET (RETURN ADDRESS) IN ERASABLE.
# 2. CALL CALL A SUBROUTINE, LEAVING RETURN IN QPRET.
# 3. RTB RETURN TO BASIC LANGUAGE AT THE GIVEN ADDRESS.
# 4. BHIZ BRANCH IF THE HIGH ORDER OF MPAC IS ZERO (SINGLE PRECISION).
# 5. BOV BRANCH ON OVERFLOW.
# 6. GOTO SIMPLE SEQUENCE CHANGE.
RTB/BHIZ CCS CYR
RTB CA POLISH
TC SWCALL -1 # SO A "TC Q" FROM ROUTINE LEADS TO DANZIG
BHIZ CCS MPAC
TCF DANZIG
TCF GOTO
TCF DANZIG
TCF GOTO
BOV(B) CCS OVFIND # BRANCH ON OVERFLOW TO BASIC OR INTERP.
TCF +2
TCF DANZIG
TS OVFIND
CCS CYR
TCF RTB # IF BASIC.
B5TOBB OCT 360
TCF GOTO
# Page 1091
BZE/GOTO CCS CYR # SEE WHICH OP-CODE IS DESIRED.
TC BRANCH # DO BZE.
TCF DANZIG
TCF GOTO # DO GOTO.
TCF DANZIG
BPL/BMN CCS CYR
TCF BPL
5B10 DEC 5 B+10 # SHIFTS OP CODE IN SWITCH INSTRUCTION ADR
TC BRANCH # DO BMN
TCF DANZIG
TCF DANZIG
TCF GOTO # ONLY IF NNZ.
BPL TC BRANCH
TCF GOTO # IF POSITIVE OR ZERO.
TCF GOTO
TCF DANZIG
CALL/ITA CCS CYR
TCF CALL
TC CCSHOLE
TC 15ADRERS # STORE QPRET. (TAGSUB AFTER 15ADRERS IS
INDEX FIXLOC # SLOW IN THIS CASE, BUT SAVES STORAGE.)
CA QPRET
TCF MSTORE1
# Page 1092
# THE FOLLOWING OPERATIONS ARE AVAILABLE FOR ALTERING AND TESTING INTERPRETATIVE SWITCHES:
# 00 BONSET SET A SWITCH AND DO A GOTO IF IT WAS ON.
# 01 SETGO SET A SWITCH AND DO A GOTO.
# 02 BOFSET SET A SWITCH AND DOA GOTO IF IT WAS OFF
# 03 SET SET A SWITCH.
# 04 BONINV INVERT A SWITCH AND BRANCH IF IT WAS ON.
# 05 INVGO INVERT A SWITCH AND DO A GOTO.
# 06 BOFINV INVERT A SWITCH AND BRANCH IF IT WAS OFF
# 07 INVERT INVERT A SWITCH.
# 10 BONCLR CLEAR A SWITCH AND BRANCH IF IT WAS ON.
# 11 CLRGO CLEAR A SWITCH AND DO A GOTO.
# 12 BOFCLR CLEAR A SWITCH AND BRANCH IF IT WAS OFF.
# 13 CLEAR CLEAR A SWITCH.
# 14 BON BRANCH IF A SWITCH WAS ON.
# 16 BOFF BRANCH IF A SWITCH WAS OFF.
# THE ADDRESS SUPPLIED WITH THE SWITCH INSTRUCTION IS INTERPRETED AS FOLLOWS:
# BITS 1-4 SWITCH BIT NUMBER (1-15).
# BITS 5-8 SWITCH OPERATION NUMBER
# BITS 9- SWITCH WORD NUMBER (UP TO 64 SWITCH WORDS).
# THE ADDRESS ITSELF IS MADE UP BY THE YUL SYSTEM ASSEMBLER. THE BRANCH INSTRUCTIONS REQUIRE TWO
# ADDRESSES, THE SECOND TAKEN AS THE DIRECT (OR INDIRECT IF IN ERASABLE) ADDRESS OF THE BRANCH.
SWITCHES CAF LOW4 # LEAVE THE SWITCH BIT IN SWBIT.
MASK POLISH
INDEX A
CAF BIT15 # (NUMBER FROM LEFT TO RIGHT.)
TS SWBIT
CAF BIT7 # LEAVE THE SWITCH NUMBER IN SWWORD.
EXTEND
MP POLISH
TS SWWORD
INHINT # DURING SWITCH CHANGE SO RUPT CAN USE TOO
INDEX A # LEAVE THE SWITCH WORD ITSELF IN L.
CA STATE
TS Q # Q WILL BE USED AS A CHANNEL.
# Page 1093
CAF BIT11
EXTEND # DISPATCH SWITCH BIT OPERATION AS IN BITS
MP POLISH # 7-8 OF POLISH.
MASK B3TOB4 # GETS 4X2-BIT CODE.
INDEX A
TCF +1
+1 CA SWBIT # 00 -- SET SWITCH IN QUESTION.
EXTEND
ROR QCHAN
TCF SWSTORE
+5 CA SWBIT # 01 -- INVERT SWITCH.
EXTEND
RXOR QCHAN
TCF SWSTORE
+9D CS SWBIT # 10 -- CLEAR.
MASK Q
SWSTORE INDEX SWWORD
TS STATE # NEW SWITCH WORD.
# Page 1094
+13D RELINT # 11 -- NOOP.
CAF BIT13
EXTEND # DISPATCH SEQUENCE CHANGING OR BRANCING
MP POLISH # CODE.
MASK B3TOB4
INDEX A
TCF +1 # ORIGINALLY STORED IN BITS 5-6
+1 CS Q # 00 -- BRANCH IF ON.
TEST MASK SWBIT
CCS A
TCF SWSKIP
+5 TCF SWBRANCH # 01 -- GO TO.
TCF SWSKIP # HERE ONLY ON BIT 15.
TC CCSHOLE
TC CCSHOLE
+9D CA Q # 10 -- BRANCH IF OFF.
TCF TEST
B3TOB4 OCT 0014
SWSKIP INCR LOC
SW/ EQUALS SWITCHES
+13D TCF DANZIG # 11 -- NOOP.
